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Tree Models

Hetero SecureBoost

Gradient Boosting Decision Tree(GBDT) is a widely used statistic model for classification and regression problems. FATE provides a novel lossless privacy-preserving tree-boosting system known as SecureBoost: A Lossless Federated Learning Framework.

This federated learning system allows a learning process to be jointly conducted over multiple parties with partially common user samples but different feature sets, which corresponds to a vertically partitioned data set. An advantage of SecureBoost is that it provides the same level of accuracy as the non privacy-preserving approach while revealing no information on private data.

The following figure shows the proposed Federated SecureBoost framework.

Figure 1: Framework of Federated SecureBoost

  • Active Party

    We define the active party as the data provider who holds both a data matrix and the class label. Since the class label information is indispensable for supervised learning, there must be an active party with access to the label y. The active party naturally takes the responsibility as a dominating server in federated learning.

  • Passive Party

    We define the data provider which has only a data matrix as a passive party. Passive parties play the role of clients in the federated learning setting. They are also in need of building a model to predict the class label y for their prediction purposes. Thus they must collaborate with the active party to build their model to predict y for their future users using their own features.

We align the data samples under an encryption scheme by using the privacy-preserving protocol for inter-database intersections to find the common shared users or data samples across the parties without compromising the non-shared parts of the user sets.

To ensure security, passive parties cannot get access to gradient and hessian directly. We use a "XGBoost" like tree-learning algorithm. In order to keep gradient and hessian confidential, we require that the active party encrypt gradient and hessian before sending them to passive parties. After encrypted the gradient and hessian, active party will send the encrypted [gradient] and [hessian] to passive party. Each passive party uses [gradient] and [hessian] to calculate the encrypted feature histograms, then encodes the (feature, split_bin_val) and constructs a (feature, split_bin_val) lookup table; it then sends the encoded value of (feature, split_bin_val) with feature histograms to the active party. After receiving the feature histograms from passive parties, the active party decrypts them and finds the best gains. If the best-gain feature belongs to a passive party, the active party sends the encoded (feature, split_bin_val) to back to the owner party. The following figure shows the process of finding split in federated tree building.

Figure 2: Process of Federated Split Finding

The parties continue the split finding process until tree construction finishes. Each party only knows the detailed split information of the tree nodes where the split features are provided by the party. The following figure shows the final structure of a single decision tree.

Figure 3: A Single Decision Tree

To use the learned model to classify a new instance, the active party first judges where current tree node belongs to. If the current tree belongs to the active party, then it can use its (feature, split_bin_val) lookup table to decide whether going to left child node or right; otherwise, the active party sends the node id to designated passive party, the passive party checks its lookup table and sends back which branch should the current node goes to. This process stops until the current node is a leave. The following figure shows the federated inference process.

Figure 4: Process of Federated Inference

By following the SecureBoost framework, multiple parties can jointly build tree ensemble model without leaking privacy in federated learning. If you want to learn more about the algorithm, you can read the paper attached above.

Optimization in Parallel Learning

SecureBoost uses data parallel learning algorithm to build the decision trees in every party. The procedure of the data parallel algorithm in each party is:

  • Every party use mapPartitions API interface to generate feature-histograms of each partition of data.
  • Use reduce API interface to merge global histograms from all local feature-histograms
  • Find the best splits from merged global histograms by federated learning, then perform splits.

Applications

Hetero SecureBoost supports the following applications.

  • binary classification, the objective function is sigmoid cross-entropy
  • multi classification, the objective function is softmax cross-entropy
  • regression, objective function includes least-squared-error-loss、least-absolutely-error-loss、huber-loss、 tweedie-loss、fair-loss、 log-cosh-loss

Other features

  • Column sub-sample
  • Controlling the number of nodes to split parallelly at each layer by setting max_split_nodes parameter,in order to avoid memory limit exceeding
  • Support feature importance calculation
  • Support Multi-host and single guest to build model
  • Support different encrypt-mode to balance speed and security
  • Support missing value in train and predict process
  • Support evaluate training and validate data during training process
  • Support another homomorphic encryption method called "Iterative Affine" since FATE-1.1
  • Support early stopping in FATE-1.4, to use early stopping, see Boosting Tree Param
  • Support sparse data optimization in FATE-1.5. You can activate it by setting "sparse_optimization" as true in conf. Notice that this feature may increase memory consumption. See here.
  • Support feature subsample random seed setting in FATE-1.5
  • Support feature binning error setting
  • Support GOSS sampling in FATE-1.6
  • Support cipher compressing and g, h packing in FATE-1.7

Homo SecureBoost

Unlike Hetero Secureboost, Homo SecureBoost is conducted under a different setting. In homo SecureBoost, every participant(clients) holds data that shares the same feature space, and jointly train a GBDT model without leaking any data sample.

The figure below shows the overall framework of the homo SecureBoost algorithm.

Figure 1: Framework of Homo SecureBoost

  • Client
    Clients are the participants who hold their labeled samples. Samples from all client parties have the same feature space. Clients are to build a more powerful model together without leaking local samples, and they share the same trained model after learning.

  • Server
    There are potentials of data leakage if all participants send its local histogram(which contains sum of gradient and hessian) to each other because sometimes features and labels can be inferred from gradient sums and hessian sums. Thus, to ensure security in the learning process, the Server uses secure aggregation to aggregate all participants' local histograms in a safe manner. The server can get a global histogram while not getting any local histogram and then find and broadcast the best splits to clients. Server collaborates with all clients in the learning process.

The key steps of learning a Homo SecureBoost model are described below:

  1. Clients and Server initialize local settings. Clients and Server apply homo feature binning to get binning points for all features and then to pre-process local samples.
  2. Clients and Server build a decision tree collaboratively:

    a. Clients compute local histograms for cur leaf nodes (left nodes or root node)

    b. The server applies secure aggregations: every local histogram plus a random number, and these numbers can cancel each other out. By this way server can get the global histogram without knowing any local histograms and data leakage is prevented. Figure below shows how histogram secure aggregations are conducted.

    Figure 2: Secure aggregation

    c. The server commit histogram subtractions: getting the right node histograms by subtracting left node local histogram from parent node histogram. Then, the server will find the best splits points and broadcast them to clients.

    d. After getting the best split points, clients build the next layer for the current decision tree and re-assign samples. If current decision tree reaches the max depth or stop conditions are fulfilled, stop build the current tree, else go back to step (1). Figure below shows the procedure of fitting a decision tree.

    Figure 3: Example of bulding a two-layer homo-decision tree

  3. If tree number reaches the max number, or loss is converged, Homo SecureBoost Fitting process stops.

By following the steps above clients are able to jointly build a GBDT model. Every client can then conduct inference on a new instance locally.

Optimization in learning

Homo SecureBoost utilizes data parallelization and histogram subtraction to accelerate the learning process.

  • Every party use mapPartitions and reduce API interface to generate local feature-histograms, only samples in left nodes are used in computing feature histograms.
  • The server aggregates all local histograms to get global histograms then get sibling histograms by subtracting left node histograms from parent histograms.
  • The server finds the best splits from merged global histograms, then broadcast best splits.
  • The computational cost and transmission cost are halved by using node subtraction.

Applications

Homo SecureBoost supports the following applications:

  • binary classification, the objective function is sigmoid cross-entropy
  • multi classification, the objective function is softmax cross-entropy
  • regression, objective function includes least-squared-error-loss, least-absolutely-error-loss, huber-loss, tweedie-loss, fair-loss, log-cosh-loss

Other features

  • Server uses safe aggregations to aggregate clients' histograms and losses, ensuring data security
  • Column sub-sample
  • Controlling the number of nodes to split parallelly at each layer by setting max_split_nodes parameter,in order to avoid memory limit exceeding
  • Support feature importance calculation
  • Support Multi-host and single guest to build model
  • Support missing value in train and predict process
  • Support evaluate training and validate data during training process
  • Support feature subsample random seed setting in FATE-1.5
  • Support feature binning error setting.

Param

boosting_param

hetero_deprecated_param_list
homo_deprecated_param_list

Classes

ObjectiveParam (BaseParam)

Define objective parameters that used in federated ml.

Parameters:

Name Type Description Default
objective {None, 'cross_entropy', 'lse', 'lae', 'log_cosh', 'tweedie', 'fair', 'huber'}

None in host's config, should be str in guest'config. when task_type is classification, only support 'cross_entropy', other 6 types support in regression task

'cross_entropy'
params None or list

should be non empty list when objective is 'tweedie','fair','huber', first element of list shoulf be a float-number large than 0.0 when objective is 'fair', 'huber', first element of list should be a float-number in [1.0, 2.0) when objective is 'tweedie'

None
Source code in federatedml/param/boosting_param.py
class ObjectiveParam(BaseParam):
    """
    Define objective parameters that used in federated ml.

    Parameters
    ----------
    objective : {None, 'cross_entropy', 'lse', 'lae', 'log_cosh', 'tweedie', 'fair', 'huber'}
        None in host's config, should be str in guest'config.
        when task_type is classification, only support 'cross_entropy',
        other 6 types support in regression task

    params : None or list
        should be non empty list when objective is 'tweedie','fair','huber',
        first element of list shoulf be a float-number large than 0.0 when objective is 'fair', 'huber',
        first element of list should be a float-number in [1.0, 2.0) when objective is 'tweedie'
    """

    def __init__(self, objective='cross_entropy', params=None):
        self.objective = objective
        self.params = params

    def check(self, task_type=None):
        if self.objective is None:
            return True

        descr = "objective param's"

        LOGGER.debug('check objective {}'.format(self.objective))

        if task_type not in [consts.CLASSIFICATION, consts.REGRESSION]:
            self.objective = self.check_and_change_lower(self.objective,
                                                   ["cross_entropy", "lse", "lae", "huber", "fair",
                                                    "log_cosh", "tweedie"],
                                                       descr)

        if task_type == consts.CLASSIFICATION:
            if self.objective != "cross_entropy":
                raise ValueError("objective param's objective {} not supported".format(self.objective))

        elif task_type == consts.REGRESSION:
            self.objective = self.check_and_change_lower(self.objective,
                                                               ["lse", "lae", "huber", "fair", "log_cosh", "tweedie"],
                                                               descr)

            params = self.params
            if self.objective in ["huber", "fair", "tweedie"]:
                if type(params).__name__ != 'list' or len(params) < 1:
                    raise ValueError(
                        "objective param's params {} not supported, should be non-empty list".format(params))

                if type(params[0]).__name__ not in ["float", "int", "long"]:
                    raise ValueError("objective param's params[0] {} not supported".format(self.params[0]))

                if self.objective == 'tweedie':
                    if params[0] < 1 or params[0] >= 2:
                        raise ValueError("in tweedie regression, objective params[0] should betweend [1, 2)")

                if self.objective == 'fair' or 'huber':
                    if params[0] <= 0.0:
                        raise ValueError("in {} regression, objective params[0] should greater than 0.0".format(
                            self.objective))
        return True
__init__(self, objective='cross_entropy', params=None) special
Source code in federatedml/param/boosting_param.py
def __init__(self, objective='cross_entropy', params=None):
    self.objective = objective
    self.params = params
check(self, task_type=None)
Source code in federatedml/param/boosting_param.py
def check(self, task_type=None):
    if self.objective is None:
        return True

    descr = "objective param's"

    LOGGER.debug('check objective {}'.format(self.objective))

    if task_type not in [consts.CLASSIFICATION, consts.REGRESSION]:
        self.objective = self.check_and_change_lower(self.objective,
                                               ["cross_entropy", "lse", "lae", "huber", "fair",
                                                "log_cosh", "tweedie"],
                                                   descr)

    if task_type == consts.CLASSIFICATION:
        if self.objective != "cross_entropy":
            raise ValueError("objective param's objective {} not supported".format(self.objective))

    elif task_type == consts.REGRESSION:
        self.objective = self.check_and_change_lower(self.objective,
                                                           ["lse", "lae", "huber", "fair", "log_cosh", "tweedie"],
                                                           descr)

        params = self.params
        if self.objective in ["huber", "fair", "tweedie"]:
            if type(params).__name__ != 'list' or len(params) < 1:
                raise ValueError(
                    "objective param's params {} not supported, should be non-empty list".format(params))

            if type(params[0]).__name__ not in ["float", "int", "long"]:
                raise ValueError("objective param's params[0] {} not supported".format(self.params[0]))

            if self.objective == 'tweedie':
                if params[0] < 1 or params[0] >= 2:
                    raise ValueError("in tweedie regression, objective params[0] should betweend [1, 2)")

            if self.objective == 'fair' or 'huber':
                if params[0] <= 0.0:
                    raise ValueError("in {} regression, objective params[0] should greater than 0.0".format(
                        self.objective))
    return True
DecisionTreeParam (BaseParam)

Define decision tree parameters that used in federated ml.

Parameters:

Name Type Description Default
criterion_method {"xgboost"}, default: "xgboost"

the criterion function to use

'xgboost'
criterion_params list or dict

should be non empty and elements are float-numbers, if a list is offered, the first one is l2 regularization value, and the second one is l1 regularization value. if a dict is offered, make sure it contains key 'l1', and 'l2'. l1, l2 regularization values are non-negative floats. default: [0.1, 0] or {'l1':0, 'l2':0,1}

[0.1, 0]
max_depth positive integer

the max depth of a decision tree, default: 3

3
min_sample_split int

least quantity of nodes to split, default: 2

2
min_impurity_split float

least gain of a single split need to reach, default: 1e-3

0.001
min_child_weight float

sum of hessian needed in child nodes. default is 0

0
min_leaf_node int

when samples no more than min_leaf_node, it becomes a leave, default: 1

1
max_split_nodes positive integer

we will use no more than max_split_nodes to parallel finding their splits in a batch, for memory consideration. default is 65536

65536
feature_importance_type {'split', 'gain'}

if is 'split', feature_importances calculate by feature split times, if is 'gain', feature_importances calculate by feature split gain. default: 'split'

'split'
use_missing bool

use missing value in training process or not. default: False

False
zero_as_missing bool

regard 0 as missing value or not, will be use only if use_missing=True, default: False

False
deterministic bool

ensure stability when computing histogram. Set this to true to ensure stable result when using same data and same parameter. But it may slow down computation.

False
Source code in federatedml/param/boosting_param.py
class DecisionTreeParam(BaseParam):
    """
    Define decision tree parameters that used in federated ml.

    Parameters
    ----------
    criterion_method : {"xgboost"}, default: "xgboost"
        the criterion function to use

    criterion_params: list or dict
        should be non empty and elements are float-numbers,
        if a list is offered, the first one is l2 regularization value, and the second one is
        l1 regularization value.
        if a dict is offered, make sure it contains key 'l1', and 'l2'.
        l1, l2 regularization values are non-negative floats.
        default: [0.1, 0] or {'l1':0, 'l2':0,1}

    max_depth: positive integer
        the max depth of a decision tree, default: 3

    min_sample_split: int
        least quantity of nodes to split, default: 2

    min_impurity_split: float
        least gain of a single split need to reach, default: 1e-3

    min_child_weight: float
        sum of hessian needed in child nodes. default is 0

    min_leaf_node: int
        when samples no more than min_leaf_node, it becomes a leave, default: 1

    max_split_nodes: positive integer
        we will use no more than max_split_nodes to
        parallel finding their splits in a batch, for memory consideration. default is 65536

    feature_importance_type: {'split', 'gain'}
        if is 'split', feature_importances calculate by feature split times,
        if is 'gain', feature_importances calculate by feature split gain.
        default: 'split'

    use_missing: bool
        use missing value in training process or not. default: False

    zero_as_missing: bool
        regard 0 as missing value or not,
        will be use only if use_missing=True, default: False

    deterministic: bool
        ensure stability when computing histogram. Set this to true to ensure stable result when using
        same data and same parameter. But it may slow down computation.

    """

    def __init__(self, criterion_method="xgboost", criterion_params=[0.1, 0], max_depth=3,
                 min_sample_split=2, min_impurity_split=1e-3, min_leaf_node=1,
                 max_split_nodes=consts.MAX_SPLIT_NODES, feature_importance_type="split",
                 n_iter_no_change=True, tol=0.001, min_child_weight=0,
                 use_missing=False, zero_as_missing=False, deterministic=False):

        super(DecisionTreeParam, self).__init__()

        self.criterion_method = criterion_method
        self.criterion_params = criterion_params
        self.max_depth = max_depth
        self.min_sample_split = min_sample_split
        self.min_impurity_split = min_impurity_split
        self.min_leaf_node = min_leaf_node
        self.min_child_weight = min_child_weight
        self.max_split_nodes = max_split_nodes
        self.feature_importance_type = feature_importance_type
        self.n_iter_no_change = n_iter_no_change
        self.tol = tol
        self.use_missing = use_missing
        self.zero_as_missing = zero_as_missing
        self.deterministic = deterministic

    def check(self):
        descr = "decision tree param"

        self.criterion_method = self.check_and_change_lower(self.criterion_method,
                                                             ["xgboost"],
                                                             descr)

        if len(self.criterion_params) == 0:
            raise ValueError("decisition tree param's criterio_params should be non empty")

        if type(self.criterion_params) == list:
            assert len(self.criterion_params) == 2, 'length of criterion_param should be 2: l1, l2 regularization ' \
                                                    'values are needed'
            self.check_nonnegative_number(self.criterion_params[0], 'l2 reg value')
            self.check_nonnegative_number(self.criterion_params[1], 'l1 reg value')

        elif type(self.criterion_params) == dict:
            assert 'l1' in self.criterion_params and 'l2' in self.criterion_params, 'l1 and l2 keys are needed in ' \
                                                                                    'criterion_params dict'
            self.criterion_params = [self.criterion_params['l2'], self.criterion_params['l1']]
        else:
            raise ValueError('criterion_params should be a dict or a list contains l1, l2 reg value')

        if type(self.max_depth).__name__ not in ["int", "long"]:
            raise ValueError("decision tree param's max_depth {} not supported, should be integer".format(
                self.max_depth))

        if self.max_depth < 1:
            raise ValueError("decision tree param's max_depth should be positive integer, no less than 1")

        if type(self.min_sample_split).__name__ not in ["int", "long"]:
            raise ValueError("decision tree param's min_sample_split {} not supported, should be integer".format(
                self.min_sample_split))

        if type(self.min_impurity_split).__name__ not in ["int", "long", "float"]:
            raise ValueError("decision tree param's min_impurity_split {} not supported, should be numeric".format(
                self.min_impurity_split))

        if type(self.min_leaf_node).__name__ not in ["int", "long"]:
            raise ValueError("decision tree param's min_leaf_node {} not supported, should be integer".format(
                self.min_leaf_node))

        if type(self.max_split_nodes).__name__ not in ["int", "long"] or self.max_split_nodes < 1:
            raise ValueError("decision tree param's max_split_nodes {} not supported, " + \
                             "should be positive integer between 1 and {}".format(self.max_split_nodes,
                                                                                  consts.MAX_SPLIT_NODES))

        if type(self.n_iter_no_change).__name__ != "bool":
            raise ValueError("decision tree param's n_iter_no_change {} not supported, should be bool type".format(
                self.n_iter_no_change))

        if type(self.tol).__name__ not in ["float", "int", "long"]:
            raise ValueError("decision tree param's tol {} not supported, should be numeric".format(self.tol))

        self.feature_importance_type = self.check_and_change_lower(self.feature_importance_type,
                                                                    ["split", "gain"],
                                                                    descr)

        self.check_nonnegative_number(self.min_child_weight, 'min_child_weight')
        self.check_boolean(self.deterministic, 'deterministic')

        return True
__init__(self, criterion_method='xgboost', criterion_params=[0.1, 0], max_depth=3, min_sample_split=2, min_impurity_split=0.001, min_leaf_node=1, max_split_nodes=65536, feature_importance_type='split', n_iter_no_change=True, tol=0.001, min_child_weight=0, use_missing=False, zero_as_missing=False, deterministic=False) special
Source code in federatedml/param/boosting_param.py
def __init__(self, criterion_method="xgboost", criterion_params=[0.1, 0], max_depth=3,
             min_sample_split=2, min_impurity_split=1e-3, min_leaf_node=1,
             max_split_nodes=consts.MAX_SPLIT_NODES, feature_importance_type="split",
             n_iter_no_change=True, tol=0.001, min_child_weight=0,
             use_missing=False, zero_as_missing=False, deterministic=False):

    super(DecisionTreeParam, self).__init__()

    self.criterion_method = criterion_method
    self.criterion_params = criterion_params
    self.max_depth = max_depth
    self.min_sample_split = min_sample_split
    self.min_impurity_split = min_impurity_split
    self.min_leaf_node = min_leaf_node
    self.min_child_weight = min_child_weight
    self.max_split_nodes = max_split_nodes
    self.feature_importance_type = feature_importance_type
    self.n_iter_no_change = n_iter_no_change
    self.tol = tol
    self.use_missing = use_missing
    self.zero_as_missing = zero_as_missing
    self.deterministic = deterministic
check(self)
Source code in federatedml/param/boosting_param.py
def check(self):
    descr = "decision tree param"

    self.criterion_method = self.check_and_change_lower(self.criterion_method,
                                                         ["xgboost"],
                                                         descr)

    if len(self.criterion_params) == 0:
        raise ValueError("decisition tree param's criterio_params should be non empty")

    if type(self.criterion_params) == list:
        assert len(self.criterion_params) == 2, 'length of criterion_param should be 2: l1, l2 regularization ' \
                                                'values are needed'
        self.check_nonnegative_number(self.criterion_params[0], 'l2 reg value')
        self.check_nonnegative_number(self.criterion_params[1], 'l1 reg value')

    elif type(self.criterion_params) == dict:
        assert 'l1' in self.criterion_params and 'l2' in self.criterion_params, 'l1 and l2 keys are needed in ' \
                                                                                'criterion_params dict'
        self.criterion_params = [self.criterion_params['l2'], self.criterion_params['l1']]
    else:
        raise ValueError('criterion_params should be a dict or a list contains l1, l2 reg value')

    if type(self.max_depth).__name__ not in ["int", "long"]:
        raise ValueError("decision tree param's max_depth {} not supported, should be integer".format(
            self.max_depth))

    if self.max_depth < 1:
        raise ValueError("decision tree param's max_depth should be positive integer, no less than 1")

    if type(self.min_sample_split).__name__ not in ["int", "long"]:
        raise ValueError("decision tree param's min_sample_split {} not supported, should be integer".format(
            self.min_sample_split))

    if type(self.min_impurity_split).__name__ not in ["int", "long", "float"]:
        raise ValueError("decision tree param's min_impurity_split {} not supported, should be numeric".format(
            self.min_impurity_split))

    if type(self.min_leaf_node).__name__ not in ["int", "long"]:
        raise ValueError("decision tree param's min_leaf_node {} not supported, should be integer".format(
            self.min_leaf_node))

    if type(self.max_split_nodes).__name__ not in ["int", "long"] or self.max_split_nodes < 1:
        raise ValueError("decision tree param's max_split_nodes {} not supported, " + \
                         "should be positive integer between 1 and {}".format(self.max_split_nodes,
                                                                              consts.MAX_SPLIT_NODES))

    if type(self.n_iter_no_change).__name__ != "bool":
        raise ValueError("decision tree param's n_iter_no_change {} not supported, should be bool type".format(
            self.n_iter_no_change))

    if type(self.tol).__name__ not in ["float", "int", "long"]:
        raise ValueError("decision tree param's tol {} not supported, should be numeric".format(self.tol))

    self.feature_importance_type = self.check_and_change_lower(self.feature_importance_type,
                                                                ["split", "gain"],
                                                                descr)

    self.check_nonnegative_number(self.min_child_weight, 'min_child_weight')
    self.check_boolean(self.deterministic, 'deterministic')

    return True
BoostingParam (BaseParam)

Basic parameter for Boosting Algorithms

Parameters:

Name Type Description Default
task_type {'classification', 'regression'}, default: 'classification'

task type

'classification'
objective_param ObjectiveParam Object, default: ObjectiveParam()

objective param

<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a6a3810>
learning_rate float, int or long

the learning rate of secure boost. default: 0.3

0.3
num_trees int or float

the max number of boosting round. default: 5

5
subsample_feature_rate float

a float-number in [0, 1], default: 1.0

1
n_iter_no_change bool,

when True and residual error less than tol, tree building process will stop. default: True

True
bin_num positive integer greater than 1

bin number use in quantile. default: 32

32
validation_freqs None or positive integer or container object in python

Do validation in training process or Not. if equals None, will not do validation in train process; if equals positive integer, will validate data every validation_freqs epochs passes; if container object in python, will validate data if epochs belong to this container. e.g. validation_freqs = [10, 15], will validate data when epoch equals to 10 and 15. Default: None

None
Source code in federatedml/param/boosting_param.py
class BoostingParam(BaseParam):
    """
    Basic parameter for Boosting Algorithms

    Parameters
    ----------
    task_type : {'classification', 'regression'}, default: 'classification'
        task type

    objective_param : ObjectiveParam Object, default: ObjectiveParam()
        objective param

    learning_rate : float, int or long
        the learning rate of secure boost. default: 0.3

    num_trees : int or float
        the max number of boosting round. default: 5

    subsample_feature_rate : float
        a float-number in [0, 1], default: 1.0

    n_iter_no_change : bool,
        when True and residual error less than tol, tree building process will stop. default: True

    bin_num: positive integer greater than 1
        bin number use in quantile. default: 32

    validation_freqs: None or positive integer or container object in python
        Do validation in training process or Not.
        if equals None, will not do validation in train process;
        if equals positive integer, will validate data every validation_freqs epochs passes;
        if container object in python, will validate data if epochs belong to this container.
        e.g. validation_freqs = [10, 15], will validate data when epoch equals to 10 and 15.
        Default: None
        """

    def __init__(self,  task_type=consts.CLASSIFICATION,
                 objective_param=ObjectiveParam(),
                 learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
                 tol=0.0001, bin_num=32,
                 predict_param=PredictParam(), cv_param=CrossValidationParam(),
                 validation_freqs=None, metrics=None, random_seed=100,
                 binning_error=consts.DEFAULT_RELATIVE_ERROR):

        super(BoostingParam, self).__init__()

        self.task_type = task_type
        self.objective_param = copy.deepcopy(objective_param)
        self.learning_rate = learning_rate
        self.num_trees = num_trees
        self.subsample_feature_rate = subsample_feature_rate
        self.n_iter_no_change = n_iter_no_change
        self.tol = tol
        self.bin_num = bin_num
        self.predict_param = copy.deepcopy(predict_param)
        self.cv_param = copy.deepcopy(cv_param)
        self.validation_freqs = validation_freqs
        self.metrics = metrics
        self.random_seed = random_seed
        self.binning_error = binning_error

    def check(self):

        descr = "boosting tree param's"

        if self.task_type not in [consts.CLASSIFICATION, consts.REGRESSION]:
            raise ValueError("boosting_core tree param's task_type {} not supported, should be {} or {}".format(
                self.task_type, consts.CLASSIFICATION, consts.REGRESSION))

        self.objective_param.check(self.task_type)

        if type(self.learning_rate).__name__ not in ["float", "int", "long"]:
            raise ValueError("boosting_core tree param's learning_rate {} not supported, should be numeric".format(
                self.learning_rate))

        if type(self.subsample_feature_rate).__name__ not in ["float", "int", "long"] or \
                self.subsample_feature_rate < 0 or self.subsample_feature_rate > 1:
            raise ValueError("boosting_core tree param's subsample_feature_rate should be a numeric number between 0 and 1")

        if type(self.n_iter_no_change).__name__ != "bool":
            raise ValueError("boosting_core tree param's n_iter_no_change {} not supported, should be bool type".format(
                self.n_iter_no_change))

        if type(self.tol).__name__ not in ["float", "int", "long"]:
            raise ValueError("boosting_core tree param's tol {} not supported, should be numeric".format(self.tol))

        if type(self.bin_num).__name__ not in ["int", "long"] or self.bin_num < 2:
            raise ValueError(
                "boosting_core tree param's bin_num {} not supported, should be positive integer greater than 1".format(
                    self.bin_num))

        if self.validation_freqs is None:
            pass
        elif isinstance(self.validation_freqs, int):
            if self.validation_freqs < 1:
                raise ValueError("validation_freqs should be larger than 0 when it's integer")
        elif not isinstance(self.validation_freqs, collections.Container):
            raise ValueError("validation_freqs should be None or positive integer or container")

        if self.metrics is not None and not isinstance(self.metrics, list):
            raise ValueError("metrics should be a list")

        if self.random_seed is not None:
            assert type(self.random_seed) == int and self.random_seed >= 0, 'random seed must be an integer >= 0'

        self.check_decimal_float(self.binning_error, descr)

        return True
__init__(self, task_type='classification', objective_param=<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a6a3810>, learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True, tol=0.0001, bin_num=32, predict_param=<federatedml.param.predict_param.PredictParam object at 0x7f3f8a6a3910>, cv_param=<federatedml.param.cross_validation_param.CrossValidationParam object at 0x7f3f8a6a3a10>, validation_freqs=None, metrics=None, random_seed=100, binning_error=0.0001) special
Source code in federatedml/param/boosting_param.py
def __init__(self,  task_type=consts.CLASSIFICATION,
             objective_param=ObjectiveParam(),
             learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
             tol=0.0001, bin_num=32,
             predict_param=PredictParam(), cv_param=CrossValidationParam(),
             validation_freqs=None, metrics=None, random_seed=100,
             binning_error=consts.DEFAULT_RELATIVE_ERROR):

    super(BoostingParam, self).__init__()

    self.task_type = task_type
    self.objective_param = copy.deepcopy(objective_param)
    self.learning_rate = learning_rate
    self.num_trees = num_trees
    self.subsample_feature_rate = subsample_feature_rate
    self.n_iter_no_change = n_iter_no_change
    self.tol = tol
    self.bin_num = bin_num
    self.predict_param = copy.deepcopy(predict_param)
    self.cv_param = copy.deepcopy(cv_param)
    self.validation_freqs = validation_freqs
    self.metrics = metrics
    self.random_seed = random_seed
    self.binning_error = binning_error
check(self)
Source code in federatedml/param/boosting_param.py
def check(self):

    descr = "boosting tree param's"

    if self.task_type not in [consts.CLASSIFICATION, consts.REGRESSION]:
        raise ValueError("boosting_core tree param's task_type {} not supported, should be {} or {}".format(
            self.task_type, consts.CLASSIFICATION, consts.REGRESSION))

    self.objective_param.check(self.task_type)

    if type(self.learning_rate).__name__ not in ["float", "int", "long"]:
        raise ValueError("boosting_core tree param's learning_rate {} not supported, should be numeric".format(
            self.learning_rate))

    if type(self.subsample_feature_rate).__name__ not in ["float", "int", "long"] or \
            self.subsample_feature_rate < 0 or self.subsample_feature_rate > 1:
        raise ValueError("boosting_core tree param's subsample_feature_rate should be a numeric number between 0 and 1")

    if type(self.n_iter_no_change).__name__ != "bool":
        raise ValueError("boosting_core tree param's n_iter_no_change {} not supported, should be bool type".format(
            self.n_iter_no_change))

    if type(self.tol).__name__ not in ["float", "int", "long"]:
        raise ValueError("boosting_core tree param's tol {} not supported, should be numeric".format(self.tol))

    if type(self.bin_num).__name__ not in ["int", "long"] or self.bin_num < 2:
        raise ValueError(
            "boosting_core tree param's bin_num {} not supported, should be positive integer greater than 1".format(
                self.bin_num))

    if self.validation_freqs is None:
        pass
    elif isinstance(self.validation_freqs, int):
        if self.validation_freqs < 1:
            raise ValueError("validation_freqs should be larger than 0 when it's integer")
    elif not isinstance(self.validation_freqs, collections.Container):
        raise ValueError("validation_freqs should be None or positive integer or container")

    if self.metrics is not None and not isinstance(self.metrics, list):
        raise ValueError("metrics should be a list")

    if self.random_seed is not None:
        assert type(self.random_seed) == int and self.random_seed >= 0, 'random seed must be an integer >= 0'

    self.check_decimal_float(self.binning_error, descr)

    return True
HeteroBoostingParam (BoostingParam)

Parameters:

Name Type Description Default
encrypt_param EncodeParam Object

encrypt method use in secure boost, default: EncryptParam()

<federatedml.param.encrypt_param.EncryptParam object at 0x7f3f8a6a3ad0>
encrypted_mode_calculator_param EncryptedModeCalculatorParam object

the calculation mode use in secureboost, default: EncryptedModeCalculatorParam()

<federatedml.param.encrypted_mode_calculation_param.EncryptedModeCalculatorParam object at 0x7f3f8a6a3b90>
Source code in federatedml/param/boosting_param.py
class HeteroBoostingParam(BoostingParam):

    """
    Parameters
    ----------
    encrypt_param : EncodeParam Object
        encrypt method use in secure boost, default: EncryptParam()

    encrypted_mode_calculator_param: EncryptedModeCalculatorParam object
        the calculation mode use in secureboost,
        default: EncryptedModeCalculatorParam()
    """

    def __init__(self, task_type=consts.CLASSIFICATION,
                 objective_param=ObjectiveParam(),
                 learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
                 tol=0.0001, encrypt_param=EncryptParam(),
                 bin_num=32,
                 encrypted_mode_calculator_param=EncryptedModeCalculatorParam(),
                 predict_param=PredictParam(), cv_param=CrossValidationParam(),
                 validation_freqs=None, early_stopping_rounds=None, metrics=None, use_first_metric_only=False,
                 random_seed=100, binning_error=consts.DEFAULT_RELATIVE_ERROR):

        super(HeteroBoostingParam, self).__init__(task_type, objective_param, learning_rate, num_trees,
                                                  subsample_feature_rate, n_iter_no_change, tol, bin_num,
                                                  predict_param, cv_param, validation_freqs, metrics=metrics,
                                                  random_seed=random_seed,
                                                  binning_error=binning_error)

        self.encrypt_param = copy.deepcopy(encrypt_param)
        self.encrypted_mode_calculator_param = copy.deepcopy(encrypted_mode_calculator_param)
        self.early_stopping_rounds = early_stopping_rounds
        self.use_first_metric_only = use_first_metric_only

    def check(self):

        super(HeteroBoostingParam, self).check()
        self.encrypted_mode_calculator_param.check()
        self.encrypt_param.check()

        if self.early_stopping_rounds is None:
            pass
        elif isinstance(self.early_stopping_rounds, int):
            if self.early_stopping_rounds < 1:
                raise ValueError("early stopping rounds should be larger than 0 when it's integer")
            if self.validation_freqs is None:
                raise ValueError("validation freqs must be set when early stopping is enabled")

        if not isinstance(self.use_first_metric_only, bool):
            raise ValueError("use_first_metric_only should be a boolean")

        return True
__init__(self, task_type='classification', objective_param=<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a6a39d0>, learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True, tol=0.0001, encrypt_param=<federatedml.param.encrypt_param.EncryptParam object at 0x7f3f8a6a3ad0>, bin_num=32, encrypted_mode_calculator_param=<federatedml.param.encrypted_mode_calculation_param.EncryptedModeCalculatorParam object at 0x7f3f8a6a3b90>, predict_param=<federatedml.param.predict_param.PredictParam object at 0x7f3f8a6a3990>, cv_param=<federatedml.param.cross_validation_param.CrossValidationParam object at 0x7f3f8a6a3b10>, validation_freqs=None, early_stopping_rounds=None, metrics=None, use_first_metric_only=False, random_seed=100, binning_error=0.0001) special
Source code in federatedml/param/boosting_param.py
def __init__(self, task_type=consts.CLASSIFICATION,
             objective_param=ObjectiveParam(),
             learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
             tol=0.0001, encrypt_param=EncryptParam(),
             bin_num=32,
             encrypted_mode_calculator_param=EncryptedModeCalculatorParam(),
             predict_param=PredictParam(), cv_param=CrossValidationParam(),
             validation_freqs=None, early_stopping_rounds=None, metrics=None, use_first_metric_only=False,
             random_seed=100, binning_error=consts.DEFAULT_RELATIVE_ERROR):

    super(HeteroBoostingParam, self).__init__(task_type, objective_param, learning_rate, num_trees,
                                              subsample_feature_rate, n_iter_no_change, tol, bin_num,
                                              predict_param, cv_param, validation_freqs, metrics=metrics,
                                              random_seed=random_seed,
                                              binning_error=binning_error)

    self.encrypt_param = copy.deepcopy(encrypt_param)
    self.encrypted_mode_calculator_param = copy.deepcopy(encrypted_mode_calculator_param)
    self.early_stopping_rounds = early_stopping_rounds
    self.use_first_metric_only = use_first_metric_only
check(self)
Source code in federatedml/param/boosting_param.py
def check(self):

    super(HeteroBoostingParam, self).check()
    self.encrypted_mode_calculator_param.check()
    self.encrypt_param.check()

    if self.early_stopping_rounds is None:
        pass
    elif isinstance(self.early_stopping_rounds, int):
        if self.early_stopping_rounds < 1:
            raise ValueError("early stopping rounds should be larger than 0 when it's integer")
        if self.validation_freqs is None:
            raise ValueError("validation freqs must be set when early stopping is enabled")

    if not isinstance(self.use_first_metric_only, bool):
        raise ValueError("use_first_metric_only should be a boolean")

    return True
HeteroSecureBoostParam (HeteroBoostingParam)

Define boosting tree parameters that used in federated ml.

Parameters:

Name Type Description Default
task_type {'classification', 'regression'}, default: 'classification'

task type

'classification'
tree_param DecisionTreeParam

tree param

<federatedml.param.boosting_param.DecisionTreeParam object at 0x7f3f8a6a3c50>
objective_param ObjectiveParam Object, default: ObjectiveParam()

objective param

<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a6a3dd0>
learning_rate float, int or long

the learning rate of secure boost. default: 0.3

0.3
num_trees int or float

the max number of trees to build. default: 5

5
subsample_feature_rate float

a float-number in [0, 1], default: 1.0

1.0
random_seed int

seed that controls all random functions

100
n_iter_no_change bool,

when True and residual error less than tol, tree building process will stop. default: True

True
encrypt_param EncodeParam Object

encrypt method use in secure boost, default: EncryptParam(), this parameter is only for hetero-secureboost

<federatedml.param.encrypt_param.EncryptParam object at 0x7f3f8a6a3e50>
bin_num positive integer greater than 1

bin number use in quantile. default: 32

32
encrypted_mode_calculator_param EncryptedModeCalculatorParam object

the calculation mode use in secureboost, default: EncryptedModeCalculatorParam(), only for hetero-secureboost

<federatedml.param.encrypted_mode_calculation_param.EncryptedModeCalculatorParam object at 0x7f3f8a6a3e90>
use_missing bool

use missing value in training process or not. default: False

False
zero_as_missing bool

regard 0 as missing value or not, will be use only if use_missing=True, default: False

False
validation_freqs None or positive integer or container object in python

Do validation in training process or Not. if equals None, will not do validation in train process; if equals positive integer, will validate data every validation_freqs epochs passes; if container object in python, will validate data if epochs belong to this container. e.g. validation_freqs = [10, 15], will validate data when epoch equals to 10 and 15. Default: None The default value is None, 1 is suggested. You can set it to a number larger than 1 in order to speed up training by skipping validation rounds. When it is larger than 1, a number which is divisible by "num_trees" is recommended, otherwise, you will miss the validation scores of last training iteration.

None
early_stopping_rounds integer larger than 0

will stop training if one metric of one validation data doesn’t improve in last early_stopping_round rounds, need to set validation freqs and will check early_stopping every at every validation epoch,

None
metrics list, default: []

Specify which metrics to be used when performing evaluation during training process. If set as empty, default metrics will be used. For regression tasks, default metrics are ['root_mean_squared_error', 'mean_absolute_error'], For binary-classificatiin tasks, default metrics are ['auc', 'ks']. For multi-classification tasks, default metrics are ['accuracy', 'precision', 'recall']

None
use_first_metric_only bool

use only the first metric for early stopping

False
complete_secure bool

if use complete_secure, when use complete secure, build first tree using only guest features

False
sparse_optimization bool

Available when encrypted method is 'iterativeAffine' An optimized mode for high-dimension, sparse data.

False
run_goss bool

activate Gradient-based One-Side Sampling, which selects large gradient and small gradient samples using top_rate and other_rate.

False
top_rate float

the retain ratio of large gradient data, used when run_goss is True

0.2
other_rate float

the retain ratio of small gradient data, used when run_goss is True

0.1
cipher_compress_error {None}

This param is now abandoned

None
cipher_compress bool

default is True, use cipher compressing to reduce computation cost and transfer cost

True
Source code in federatedml/param/boosting_param.py
class HeteroSecureBoostParam(HeteroBoostingParam):
    """
    Define boosting tree parameters that used in federated ml.

    Parameters
    ----------
    task_type : {'classification', 'regression'}, default: 'classification'
        task type

    tree_param : DecisionTreeParam Object, default: DecisionTreeParam()
        tree param

    objective_param : ObjectiveParam Object, default: ObjectiveParam()
        objective param

    learning_rate : float, int or long
        the learning rate of secure boost. default: 0.3

    num_trees : int or float
        the max number of trees to build. default: 5

    subsample_feature_rate : float
        a float-number in [0, 1], default: 1.0

    random_seed: int
        seed that controls all random functions

    n_iter_no_change : bool,
        when True and residual error less than tol, tree building process will stop. default: True

    encrypt_param : EncodeParam Object
        encrypt method use in secure boost, default: EncryptParam(), this parameter
        is only for hetero-secureboost

    bin_num: positive integer greater than 1
        bin number use in quantile. default: 32

    encrypted_mode_calculator_param: EncryptedModeCalculatorParam object
        the calculation mode use in secureboost, default: EncryptedModeCalculatorParam(), only for hetero-secureboost

    use_missing: bool
        use missing value in training process or not. default: False

    zero_as_missing: bool
        regard 0 as missing value or not, will be use only if use_missing=True, default: False

    validation_freqs: None or positive integer or container object in python
        Do validation in training process or Not.
        if equals None, will not do validation in train process;
        if equals positive integer, will validate data every validation_freqs epochs passes;
        if container object in python, will validate data if epochs belong to this container.
        e.g. validation_freqs = [10, 15], will validate data when epoch equals to 10 and 15.
        Default: None
        The default value is None, 1 is suggested. You can set it to a number larger than 1 in order to
        speed up training by skipping validation rounds. When it is larger than 1, a number which is
        divisible by "num_trees" is recommended, otherwise, you will miss the validation scores
        of last training iteration.

    early_stopping_rounds: integer larger than 0
        will stop training if one metric of one validation data
        doesn’t improve in last early_stopping_round rounds,
        need to set validation freqs and will check early_stopping every at every validation epoch,

    metrics: list, default: []
        Specify which metrics to be used when performing evaluation during training process.
        If set as empty, default metrics will be used. For regression tasks, default metrics are
        ['root_mean_squared_error', 'mean_absolute_error'], For binary-classificatiin tasks, default metrics
        are ['auc', 'ks']. For multi-classification tasks, default metrics are ['accuracy', 'precision', 'recall']

    use_first_metric_only: bool
        use only the first metric for early stopping

    complete_secure: bool
        if use complete_secure, when use complete secure, build first tree using only guest features

    sparse_optimization: bool
        Available when encrypted method is 'iterativeAffine'
        An optimized mode for high-dimension, sparse data.

    run_goss: bool
        activate Gradient-based One-Side Sampling, which selects large gradient and small
        gradient samples using top_rate and other_rate.

    top_rate: float
        the retain ratio of large gradient data, used when run_goss is True

    other_rate: float
        the retain ratio of small gradient data, used when run_goss is True

    cipher_compress_error: {None}
        This param is now abandoned

    cipher_compress: bool
        default is True, use cipher compressing to reduce computation cost and transfer cost

    """

    def __init__(self, tree_param: DecisionTreeParam = DecisionTreeParam(), task_type=consts.CLASSIFICATION,
                 objective_param=ObjectiveParam(),
                 learning_rate=0.3, num_trees=5, subsample_feature_rate=1.0, n_iter_no_change=True,
                 tol=0.0001, encrypt_param=EncryptParam(),
                 bin_num=32,
                 encrypted_mode_calculator_param=EncryptedModeCalculatorParam(),
                 predict_param=PredictParam(), cv_param=CrossValidationParam(),
                 validation_freqs=None, early_stopping_rounds=None, use_missing=False, zero_as_missing=False,
                 complete_secure=False, metrics=None, use_first_metric_only=False, random_seed=100,
                 binning_error=consts.DEFAULT_RELATIVE_ERROR,
                 sparse_optimization=False, run_goss=False, top_rate=0.2, other_rate=0.1,
                 cipher_compress_error=None, cipher_compress=True, new_ver=True,
                 callback_param=CallbackParam()):

        super(HeteroSecureBoostParam, self).__init__(task_type, objective_param, learning_rate, num_trees,
                                                     subsample_feature_rate, n_iter_no_change, tol, encrypt_param,
                                                     bin_num, encrypted_mode_calculator_param, predict_param, cv_param,
                                                     validation_freqs, early_stopping_rounds, metrics=metrics,
                                                     use_first_metric_only=use_first_metric_only,
                                                     random_seed=random_seed,
                                                     binning_error=binning_error)

        self.tree_param = copy.deepcopy(tree_param)
        self.zero_as_missing = zero_as_missing
        self.use_missing = use_missing
        self.complete_secure = complete_secure
        self.sparse_optimization = sparse_optimization
        self.run_goss = run_goss
        self.top_rate = top_rate
        self.other_rate = other_rate
        self.cipher_compress_error = cipher_compress_error
        self.cipher_compress = cipher_compress
        self.new_ver = new_ver
        self.callback_param = copy.deepcopy(callback_param)

    def check(self):

        super(HeteroSecureBoostParam, self).check()
        self.tree_param.check()
        if type(self.use_missing) != bool:
            raise ValueError('use missing should be bool type')
        if type(self.zero_as_missing) != bool:
            raise ValueError('zero as missing should be bool type')
        self.check_boolean(self.complete_secure, 'complete_secure')
        self.check_boolean(self.sparse_optimization, 'sparse optimization')
        self.check_boolean(self.run_goss, 'run goss')
        self.check_decimal_float(self.top_rate, 'top rate')
        self.check_decimal_float(self.other_rate, 'other rate')
        self.check_positive_number(self.other_rate, 'other_rate')
        self.check_positive_number(self.top_rate, 'top_rate')
        self.check_boolean(self.new_ver, 'code version switcher')
        self.check_boolean(self.cipher_compress, 'cipher compress')

        for p in ["early_stopping_rounds", "validation_freqs", "metrics",
                  "use_first_metric_only"]:
            # if self._warn_to_deprecate_param(p, "", ""):
            if self._deprecated_params_set.get(p):
                if "callback_param" in self.get_user_feeded():
                    raise ValueError(f"{p} and callback param should not be set simultaneously,"
                                     f"{self._deprecated_params_set}, {self.get_user_feeded()}")
                else:
                    self.callback_param.callbacks = ["PerformanceEvaluate"]
                break

        descr = "boosting_param's"

        if self._warn_to_deprecate_param("validation_freqs", descr, "callback_param's 'validation_freqs'"):
            self.callback_param.validation_freqs = self.validation_freqs

        if self._warn_to_deprecate_param("early_stopping_rounds", descr, "callback_param's 'early_stopping_rounds'"):
            self.callback_param.early_stopping_rounds = self.early_stopping_rounds

        if self._warn_to_deprecate_param("metrics", descr, "callback_param's 'metrics'"):
            self.callback_param.metrics = self.metrics

        if self._warn_to_deprecate_param("use_first_metric_only", descr, "callback_param's 'use_first_metric_only'"):
            self.callback_param.use_first_metric_only = self.use_first_metric_only

        if self.top_rate + self.other_rate >= 1:
            raise ValueError('sum of top rate and other rate should be smaller than 1')

        if self.sparse_optimization and self.cipher_compress:
            raise ValueError('cipher compress is not supported in sparse optimization mode')

        return True
__init__(self, tree_param=<federatedml.param.boosting_param.DecisionTreeParam object at 0x7f3f8a6a3c50>, task_type='classification', objective_param=<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a6a3dd0>, learning_rate=0.3, num_trees=5, subsample_feature_rate=1.0, n_iter_no_change=True, tol=0.0001, encrypt_param=<federatedml.param.encrypt_param.EncryptParam object at 0x7f3f8a6a3e50>, bin_num=32, encrypted_mode_calculator_param=<federatedml.param.encrypted_mode_calculation_param.EncryptedModeCalculatorParam object at 0x7f3f8a6a3e90>, predict_param=<federatedml.param.predict_param.PredictParam object at 0x7f3f8a6a3e10>, cv_param=<federatedml.param.cross_validation_param.CrossValidationParam object at 0x7f3f8a6a3cd0>, validation_freqs=None, early_stopping_rounds=None, use_missing=False, zero_as_missing=False, complete_secure=False, metrics=None, use_first_metric_only=False, random_seed=100, binning_error=0.0001, sparse_optimization=False, run_goss=False, top_rate=0.2, other_rate=0.1, cipher_compress_error=None, cipher_compress=True, new_ver=True, callback_param=<federatedml.param.callback_param.CallbackParam object at 0x7f3f8a6a3f90>) special
Source code in federatedml/param/boosting_param.py
def __init__(self, tree_param: DecisionTreeParam = DecisionTreeParam(), task_type=consts.CLASSIFICATION,
             objective_param=ObjectiveParam(),
             learning_rate=0.3, num_trees=5, subsample_feature_rate=1.0, n_iter_no_change=True,
             tol=0.0001, encrypt_param=EncryptParam(),
             bin_num=32,
             encrypted_mode_calculator_param=EncryptedModeCalculatorParam(),
             predict_param=PredictParam(), cv_param=CrossValidationParam(),
             validation_freqs=None, early_stopping_rounds=None, use_missing=False, zero_as_missing=False,
             complete_secure=False, metrics=None, use_first_metric_only=False, random_seed=100,
             binning_error=consts.DEFAULT_RELATIVE_ERROR,
             sparse_optimization=False, run_goss=False, top_rate=0.2, other_rate=0.1,
             cipher_compress_error=None, cipher_compress=True, new_ver=True,
             callback_param=CallbackParam()):

    super(HeteroSecureBoostParam, self).__init__(task_type, objective_param, learning_rate, num_trees,
                                                 subsample_feature_rate, n_iter_no_change, tol, encrypt_param,
                                                 bin_num, encrypted_mode_calculator_param, predict_param, cv_param,
                                                 validation_freqs, early_stopping_rounds, metrics=metrics,
                                                 use_first_metric_only=use_first_metric_only,
                                                 random_seed=random_seed,
                                                 binning_error=binning_error)

    self.tree_param = copy.deepcopy(tree_param)
    self.zero_as_missing = zero_as_missing
    self.use_missing = use_missing
    self.complete_secure = complete_secure
    self.sparse_optimization = sparse_optimization
    self.run_goss = run_goss
    self.top_rate = top_rate
    self.other_rate = other_rate
    self.cipher_compress_error = cipher_compress_error
    self.cipher_compress = cipher_compress
    self.new_ver = new_ver
    self.callback_param = copy.deepcopy(callback_param)
check(self)
Source code in federatedml/param/boosting_param.py
def check(self):

    super(HeteroSecureBoostParam, self).check()
    self.tree_param.check()
    if type(self.use_missing) != bool:
        raise ValueError('use missing should be bool type')
    if type(self.zero_as_missing) != bool:
        raise ValueError('zero as missing should be bool type')
    self.check_boolean(self.complete_secure, 'complete_secure')
    self.check_boolean(self.sparse_optimization, 'sparse optimization')
    self.check_boolean(self.run_goss, 'run goss')
    self.check_decimal_float(self.top_rate, 'top rate')
    self.check_decimal_float(self.other_rate, 'other rate')
    self.check_positive_number(self.other_rate, 'other_rate')
    self.check_positive_number(self.top_rate, 'top_rate')
    self.check_boolean(self.new_ver, 'code version switcher')
    self.check_boolean(self.cipher_compress, 'cipher compress')

    for p in ["early_stopping_rounds", "validation_freqs", "metrics",
              "use_first_metric_only"]:
        # if self._warn_to_deprecate_param(p, "", ""):
        if self._deprecated_params_set.get(p):
            if "callback_param" in self.get_user_feeded():
                raise ValueError(f"{p} and callback param should not be set simultaneously,"
                                 f"{self._deprecated_params_set}, {self.get_user_feeded()}")
            else:
                self.callback_param.callbacks = ["PerformanceEvaluate"]
            break

    descr = "boosting_param's"

    if self._warn_to_deprecate_param("validation_freqs", descr, "callback_param's 'validation_freqs'"):
        self.callback_param.validation_freqs = self.validation_freqs

    if self._warn_to_deprecate_param("early_stopping_rounds", descr, "callback_param's 'early_stopping_rounds'"):
        self.callback_param.early_stopping_rounds = self.early_stopping_rounds

    if self._warn_to_deprecate_param("metrics", descr, "callback_param's 'metrics'"):
        self.callback_param.metrics = self.metrics

    if self._warn_to_deprecate_param("use_first_metric_only", descr, "callback_param's 'use_first_metric_only'"):
        self.callback_param.use_first_metric_only = self.use_first_metric_only

    if self.top_rate + self.other_rate >= 1:
        raise ValueError('sum of top rate and other rate should be smaller than 1')

    if self.sparse_optimization and self.cipher_compress:
        raise ValueError('cipher compress is not supported in sparse optimization mode')

    return True
HeteroFastSecureBoostParam (HeteroSecureBoostParam)
Source code in federatedml/param/boosting_param.py
class HeteroFastSecureBoostParam(HeteroSecureBoostParam):

    def __init__(self, tree_param: DecisionTreeParam = DecisionTreeParam(), task_type=consts.CLASSIFICATION,
                 objective_param=ObjectiveParam(),
                 learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
                 tol=0.0001, encrypt_param=EncryptParam(),
                 bin_num=32,
                 encrypted_mode_calculator_param=EncryptedModeCalculatorParam(),
                 predict_param=PredictParam(), cv_param=CrossValidationParam(),
                 validation_freqs=None, early_stopping_rounds=None, use_missing=False, zero_as_missing=False,
                 complete_secure=False, tree_num_per_party=1, guest_depth=1, host_depth=1, work_mode='mix', metrics=None,
                 sparse_optimization=False, random_seed=100, binning_error=consts.DEFAULT_RELATIVE_ERROR,
                 cipher_compress_error=None, new_ver=True, run_goss=False, top_rate=0.2, other_rate=0.1,
                 cipher_compress=True, callback_param=CallbackParam()):

        """
        Parameters
        ----------
        work_mode: {"mix", "layered"}
            mix:  alternate using guest/host features to build trees. For example, the first 'tree_num_per_party' trees use guest features,
                  the second k trees use host features, and so on
            layered: only support 2 party, when running layered mode, first 'host_depth' layer will use host features,
                     and then next 'guest_depth' will only use guest features
        tree_num_per_party: int
            every party will alternate build 'tree_num_per_party' trees until reach max tree num, this param is valid when work_mode is mix
        guest_depth: int
            guest will build last guest_depth of a decision tree using guest features, is valid when work mode is layered
        host depth: int
            host will build first host_depth of a decision tree using host features, is valid when work mode is layered

        """

        super(HeteroFastSecureBoostParam, self).__init__(tree_param, task_type, objective_param, learning_rate,
                                                         num_trees, subsample_feature_rate, n_iter_no_change, tol,
                                                         encrypt_param, bin_num, encrypted_mode_calculator_param,
                                                         predict_param, cv_param, validation_freqs, early_stopping_rounds,
                                                         use_missing, zero_as_missing, complete_secure, metrics=metrics,
                                                         random_seed=random_seed,
                                                         sparse_optimization=sparse_optimization,
                                                         binning_error=binning_error,
                                                         cipher_compress_error=cipher_compress_error,
                                                         new_ver=new_ver,
                                                         cipher_compress=cipher_compress,
                                                         run_goss=run_goss, top_rate=top_rate, other_rate=other_rate,
                                                         )

        self.tree_num_per_party = tree_num_per_party
        self.guest_depth = guest_depth
        self.host_depth = host_depth
        self.work_mode = work_mode
        self.callback_param = copy.deepcopy(callback_param)

    def check(self):

        super(HeteroFastSecureBoostParam, self).check()
        if type(self.guest_depth).__name__ not in ["int", "long"] or self.guest_depth <= 0:
            raise ValueError("guest_depth should be larger than 0")
        if type(self.host_depth).__name__ not in ["int", "long"] or self.host_depth <= 0:
            raise ValueError("host_depth should be larger than 0")
        if type(self.tree_num_per_party).__name__ not in ["int", "long"] or self.tree_num_per_party <= 0:
            raise ValueError("tree_num_per_party should be larger than 0")

        work_modes = [consts.MIX_TREE, consts.LAYERED_TREE]
        if self.work_mode not in work_modes:
            raise ValueError('only work_modes: {} are supported, input work mode is {}'.
                             format(work_modes, self.work_mode))

        return True
Methods
__init__(self, tree_param=<federatedml.param.boosting_param.DecisionTreeParam object at 0x7f3f8a6a3f10>, task_type='classification', objective_param=<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a6a3d50>, learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True, tol=0.0001, encrypt_param=<federatedml.param.encrypt_param.EncryptParam object at 0x7f3f8a6a3fd0>, bin_num=32, encrypted_mode_calculator_param=<federatedml.param.encrypted_mode_calculation_param.EncryptedModeCalculatorParam object at 0x7f3f8a75b050>, predict_param=<federatedml.param.predict_param.PredictParam object at 0x7f3f8a75b0d0>, cv_param=<federatedml.param.cross_validation_param.CrossValidationParam object at 0x7f3f8a75b190>, validation_freqs=None, early_stopping_rounds=None, use_missing=False, zero_as_missing=False, complete_secure=False, tree_num_per_party=1, guest_depth=1, host_depth=1, work_mode='mix', metrics=None, sparse_optimization=False, random_seed=100, binning_error=0.0001, cipher_compress_error=None, new_ver=True, run_goss=False, top_rate=0.2, other_rate=0.1, cipher_compress=True, callback_param=<federatedml.param.callback_param.CallbackParam object at 0x7f3f8a75b210>) special

Parameters:

Name Type Description Default
work_mode {"mix", "layered"} 'mix'
tree_num_per_party int

every party will alternate build 'tree_num_per_party' trees until reach max tree num, this param is valid when work_mode is mix

1
guest_depth int

guest will build last guest_depth of a decision tree using guest features, is valid when work mode is layered

1
host depth int

host will build first host_depth of a decision tree using host features, is valid when work mode is layered

required
Source code in federatedml/param/boosting_param.py
def __init__(self, tree_param: DecisionTreeParam = DecisionTreeParam(), task_type=consts.CLASSIFICATION,
             objective_param=ObjectiveParam(),
             learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
             tol=0.0001, encrypt_param=EncryptParam(),
             bin_num=32,
             encrypted_mode_calculator_param=EncryptedModeCalculatorParam(),
             predict_param=PredictParam(), cv_param=CrossValidationParam(),
             validation_freqs=None, early_stopping_rounds=None, use_missing=False, zero_as_missing=False,
             complete_secure=False, tree_num_per_party=1, guest_depth=1, host_depth=1, work_mode='mix', metrics=None,
             sparse_optimization=False, random_seed=100, binning_error=consts.DEFAULT_RELATIVE_ERROR,
             cipher_compress_error=None, new_ver=True, run_goss=False, top_rate=0.2, other_rate=0.1,
             cipher_compress=True, callback_param=CallbackParam()):

    """
    Parameters
    ----------
    work_mode: {"mix", "layered"}
        mix:  alternate using guest/host features to build trees. For example, the first 'tree_num_per_party' trees use guest features,
              the second k trees use host features, and so on
        layered: only support 2 party, when running layered mode, first 'host_depth' layer will use host features,
                 and then next 'guest_depth' will only use guest features
    tree_num_per_party: int
        every party will alternate build 'tree_num_per_party' trees until reach max tree num, this param is valid when work_mode is mix
    guest_depth: int
        guest will build last guest_depth of a decision tree using guest features, is valid when work mode is layered
    host depth: int
        host will build first host_depth of a decision tree using host features, is valid when work mode is layered

    """

    super(HeteroFastSecureBoostParam, self).__init__(tree_param, task_type, objective_param, learning_rate,
                                                     num_trees, subsample_feature_rate, n_iter_no_change, tol,
                                                     encrypt_param, bin_num, encrypted_mode_calculator_param,
                                                     predict_param, cv_param, validation_freqs, early_stopping_rounds,
                                                     use_missing, zero_as_missing, complete_secure, metrics=metrics,
                                                     random_seed=random_seed,
                                                     sparse_optimization=sparse_optimization,
                                                     binning_error=binning_error,
                                                     cipher_compress_error=cipher_compress_error,
                                                     new_ver=new_ver,
                                                     cipher_compress=cipher_compress,
                                                     run_goss=run_goss, top_rate=top_rate, other_rate=other_rate,
                                                     )

    self.tree_num_per_party = tree_num_per_party
    self.guest_depth = guest_depth
    self.host_depth = host_depth
    self.work_mode = work_mode
    self.callback_param = copy.deepcopy(callback_param)
check(self)
Source code in federatedml/param/boosting_param.py
def check(self):

    super(HeteroFastSecureBoostParam, self).check()
    if type(self.guest_depth).__name__ not in ["int", "long"] or self.guest_depth <= 0:
        raise ValueError("guest_depth should be larger than 0")
    if type(self.host_depth).__name__ not in ["int", "long"] or self.host_depth <= 0:
        raise ValueError("host_depth should be larger than 0")
    if type(self.tree_num_per_party).__name__ not in ["int", "long"] or self.tree_num_per_party <= 0:
        raise ValueError("tree_num_per_party should be larger than 0")

    work_modes = [consts.MIX_TREE, consts.LAYERED_TREE]
    if self.work_mode not in work_modes:
        raise ValueError('only work_modes: {} are supported, input work mode is {}'.
                         format(work_modes, self.work_mode))

    return True
HomoSecureBoostParam (BoostingParam)

Parameters:

Name Type Description Default
backend {'distributed', 'memory'}

decides which backend to use when computing histograms for homo-sbt

'distributed'
Source code in federatedml/param/boosting_param.py
class HomoSecureBoostParam(BoostingParam):

    """
    Parameters
    ----------
    backend: {'distributed', 'memory'}
        decides which backend to use when computing histograms for homo-sbt
    """

    def __init__(self, tree_param: DecisionTreeParam = DecisionTreeParam(), task_type=consts.CLASSIFICATION,
                 objective_param=ObjectiveParam(),
                 learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
                 tol=0.0001, bin_num=32, predict_param=PredictParam(), cv_param=CrossValidationParam(),
                 validation_freqs=None, use_missing=False, zero_as_missing=False, random_seed=100,
                 binning_error=consts.DEFAULT_RELATIVE_ERROR, backend=consts.DISTRIBUTED_BACKEND,
                 callback_param=CallbackParam()):
        super(HomoSecureBoostParam, self).__init__(task_type=task_type,
                                                   objective_param=objective_param,
                                                   learning_rate=learning_rate,
                                                   num_trees=num_trees,
                                                   subsample_feature_rate=subsample_feature_rate,
                                                   n_iter_no_change=n_iter_no_change,
                                                   tol=tol,
                                                   bin_num=bin_num,
                                                   predict_param=predict_param,
                                                   cv_param=cv_param,
                                                   validation_freqs=validation_freqs,
                                                   random_seed=random_seed,
                                                   binning_error=binning_error
                                                   )
        self.use_missing = use_missing
        self.zero_as_missing = zero_as_missing
        self.tree_param = copy.deepcopy(tree_param)
        self.backend = backend
        self.callback_param = copy.deepcopy(callback_param)

    def check(self):

        super(HomoSecureBoostParam, self).check()
        self.tree_param.check()
        if type(self.use_missing) != bool:
            raise ValueError('use missing should be bool type')
        if type(self.zero_as_missing) != bool:
            raise ValueError('zero as missing should be bool type')
        if self.backend not in [consts.MEMORY_BACKEND, consts.DISTRIBUTED_BACKEND]:
            raise ValueError('unsupported backend')

        for p in ["validation_freqs", "metrics"]:
            # if self._warn_to_deprecate_param(p, "", ""):
            if self._deprecated_params_set.get(p):
                if "callback_param" in self.get_user_feeded():
                    raise ValueError(f"{p} and callback param should not be set simultaneously,"
                                     f"{self._deprecated_params_set}, {self.get_user_feeded()}")
                else:
                    self.callback_param.callbacks = ["PerformanceEvaluate"]
                break

        descr = "boosting_param's"

        if self._warn_to_deprecate_param("validation_freqs", descr, "callback_param's 'validation_freqs'"):
            self.callback_param.validation_freqs = self.validation_freqs

        if self._warn_to_deprecate_param("metrics", descr, "callback_param's 'metrics'"):
            self.callback_param.metrics = self.metrics

        return True
__init__(self, tree_param=<federatedml.param.boosting_param.DecisionTreeParam object at 0x7f3f8a75b150>, task_type='classification', objective_param=<federatedml.param.boosting_param.ObjectiveParam object at 0x7f3f8a75b390>, learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True, tol=0.0001, bin_num=32, predict_param=<federatedml.param.predict_param.PredictParam object at 0x7f3f8a75b410>, cv_param=<federatedml.param.cross_validation_param.CrossValidationParam object at 0x7f3f8a75b450>, validation_freqs=None, use_missing=False, zero_as_missing=False, random_seed=100, binning_error=0.0001, backend='distributed', callback_param=<federatedml.param.callback_param.CallbackParam object at 0x7f3f8a75b4d0>) special
Source code in federatedml/param/boosting_param.py
def __init__(self, tree_param: DecisionTreeParam = DecisionTreeParam(), task_type=consts.CLASSIFICATION,
             objective_param=ObjectiveParam(),
             learning_rate=0.3, num_trees=5, subsample_feature_rate=1, n_iter_no_change=True,
             tol=0.0001, bin_num=32, predict_param=PredictParam(), cv_param=CrossValidationParam(),
             validation_freqs=None, use_missing=False, zero_as_missing=False, random_seed=100,
             binning_error=consts.DEFAULT_RELATIVE_ERROR, backend=consts.DISTRIBUTED_BACKEND,
             callback_param=CallbackParam()):
    super(HomoSecureBoostParam, self).__init__(task_type=task_type,
                                               objective_param=objective_param,
                                               learning_rate=learning_rate,
                                               num_trees=num_trees,
                                               subsample_feature_rate=subsample_feature_rate,
                                               n_iter_no_change=n_iter_no_change,
                                               tol=tol,
                                               bin_num=bin_num,
                                               predict_param=predict_param,
                                               cv_param=cv_param,
                                               validation_freqs=validation_freqs,
                                               random_seed=random_seed,
                                               binning_error=binning_error
                                               )
    self.use_missing = use_missing
    self.zero_as_missing = zero_as_missing
    self.tree_param = copy.deepcopy(tree_param)
    self.backend = backend
    self.callback_param = copy.deepcopy(callback_param)
check(self)
Source code in federatedml/param/boosting_param.py
def check(self):

    super(HomoSecureBoostParam, self).check()
    self.tree_param.check()
    if type(self.use_missing) != bool:
        raise ValueError('use missing should be bool type')
    if type(self.zero_as_missing) != bool:
        raise ValueError('zero as missing should be bool type')
    if self.backend not in [consts.MEMORY_BACKEND, consts.DISTRIBUTED_BACKEND]:
        raise ValueError('unsupported backend')

    for p in ["validation_freqs", "metrics"]:
        # if self._warn_to_deprecate_param(p, "", ""):
        if self._deprecated_params_set.get(p):
            if "callback_param" in self.get_user_feeded():
                raise ValueError(f"{p} and callback param should not be set simultaneously,"
                                 f"{self._deprecated_params_set}, {self.get_user_feeded()}")
            else:
                self.callback_param.callbacks = ["PerformanceEvaluate"]
            break

    descr = "boosting_param's"

    if self._warn_to_deprecate_param("validation_freqs", descr, "callback_param's 'validation_freqs'"):
        self.callback_param.validation_freqs = self.validation_freqs

    if self._warn_to_deprecate_param("metrics", descr, "callback_param's 'metrics'"):
        self.callback_param.metrics = self.metrics

    return True

Hetero Complete Secureboost

Now Hetero SecureBoost adds a new option: complete_secure. Once enabled, the boosting model will only use guest features to build the first decision tree. This can avoid label leakages, accord to SecureBoost: A Lossless Federated Learning Framework.

Figure 4: complete secure boost

Examples

Example
## Hetero SecureBoost Configuration Usage Guide.

#### Example Tasks.

1. Binary-Class:  

    example-data: (1) guest: breast_hetero_guest.csv  (2) host: breast_hetero_host.csv  

    dsl: test_secureboost_train_dsl.json  

    runtime_config: test_secureboost_train_binary_conf.json

2. Multi-Class:  

    example-data: (1) guest: vehicle_scale_hetero_guest.csv
                  (2) host: vehicle_scale_hetero_host.csv  

    dsl: test_secureboost_train_dsl.json  

    runtime_config: test_secureboost_train_multi_conf.json

3. Regression:  

    example-data: (1) guest: student_hetero_guest.csv
                  (2) host: student_hetero_host.csv  

    dsl: test_secureboost_train_dsl.json  

    runtime_config: test_secureboost_train_regression_conf.json

4. Multi-Host Regression  

    example-data: (1) guest: motor_hetero_guest.csv
                  (2) host1: motor_hetero_host_1.csv; 
                  (3) host2: motor_hetero_host_2.csv  

    dsl: test_secureboost_train_dsl.json  

    runtime_config: test_secureboost_train_regression_multi_host_conf.json

5. Binary-Class With Missing Value  

    example-data: (1) guest: ionosphere_scale_hetero_guest.csv
                  (2) host: ionosphere_scale_hetero_host.csv  

    dsl: test_secureboost_train_dsl.json  

    runtime_config: test_secureboost_train_binary_with_missing_value_conf.json  

    This example also contains another two feature since FATE-1.1.  
    (1) evaluate data during training process, check the "validation_freqs" field in runtime_config  
    (2) another homomorphic encryption method "Iterative Affine", check "encrypt_param" field in runtime_config.

6. Early stopping example

    example-data: (1) guest: student_hetero_guest.csv
                  (2) host: student_hetero_host.csv  

    dsl: test_secureboost_train_dsl.json  

    runtime_config: test_secureboost_train_with_early_stopping_conf.json


#### Cross Validation Class

1. Binary-Class:  

    example-data: (1) guest: breast_hetero_guest.csv
                  (2) host: breast_hetero_guest.csv  

    dsl: test_secureboost_cross_validation_dsl.json  

    runtime_config: test_secureboost_cross_validation_binary_conf.json 

2. Multi-Class:  

    example-data: (1) guest: vehicle_scale_hetero_guest.csv
                  (2) host: vehicle_scal_a.csv  

    dsl: test_secureboost_cross_validation_binary_conf.json 

    runtime_config: test_secureboost_cross_validation_multi_conf.json  

3. Regression:  

    example-data: (1) guest: student_hetero_guest.csv
                  (2) host: student_hetero_host.csv  

    dsl: test_secureboost_cross_validation_dsl.json  

    runtime_config: test_secureboost_cross_validation_regression_conf.json

Users can use following commands to run a task.

    flow job submit -c ${runtime_config} -d ${dsl}

Moreover, after successfully running the training task, you can use it to predict too.
test_secureboost_warm_start_dsl.json
{
    "components": {
        "reader_0": {
            "module": "Reader",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "data_transform_0": {
            "module": "DataTransform",
            "input": {
                "data": {
                    "data": [
                        "reader_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "intersection_0": {
            "module": "Intersection",
            "input": {
                "data": {
                    "data": [
                        "data_transform_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "cache": [
                    "cache"
                ]
            }
        },
        "hetero_secure_boost_0": {
            "module": "HeteroSecureBoost",
            "input": {
                "data": {
                    "train_data": [
                        "intersection_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "hetero_secure_boost_1": {
            "module": "HeteroSecureBoost",
            "input": {
                "data": {
                    "train_data": [
                        "intersection_0.data"
                    ]
                },
                "model": [
                    "hetero_secure_boost_0.model"
                ]
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "evaluation_0": {
            "module": "Evaluation",
            "input": {
                "data": {
                    "data": [
                        "hetero_secure_boost_1.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ]
            }
        }
    }
}            
test_secureboost_cross_validation_multi_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "cv_param": {
                    "need_cv": true,
                    "n_splits": 5,
                    "shuffle": false,
                    "random_seed": 103
                },
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            }
        },
        "role": {
            "host": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "vehicle_scale_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    }
                }
            },
            "guest": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "vehicle_scale_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    }
                }
            }
        }
    }
}            
test_secureboost_train_multi_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            },
            "evaluation_0": {
                "eval_type": "multi"
            }
        },
        "role": {
            "host": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "vehicle_scale_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    },
                    "reader_0": {
                        "table": {
                            "name": "vehicle_scale_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "guest": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "vehicle_scale_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "reader_0": {
                        "table": {
                            "name": "vehicle_scale_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
test_secureboost_train_regression_multi_host_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998,
            10000
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "regression",
                "objective_param": {
                    "objective": "lse"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            },
            "evaluation_0": {
                "eval_type": "regression"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "data_transform_0": {
                        "with_label": true,
                        "label_name": "motor_speed",
                        "label_type": "float",
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "label_name": "motor_speed",
                        "label_type": "float",
                        "output_format": "dense"
                    },
                    "reader_1": {
                        "table": {
                            "name": "motor_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "motor_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "host": {
                "1": {
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    },
                    "reader_1": {
                        "table": {
                            "name": "motor_hetero_host_2",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "motor_hetero_host_2",
                            "namespace": "experiment"
                        }
                    }
                },
                "0": {
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    },
                    "reader_1": {
                        "table": {
                            "name": "motor_hetero_host_1",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "motor_hetero_host_1",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
test_secureboost_train_binary_without_cipher_compress_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                },
                "cipher_compress": false
            },
            "evaluation_0": {
                "eval_type": "binary"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "output_format": "dense"
                    }
                }
            },
            "host": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    }
                }
            }
        }
    }
}            
test_secureboost_train_binary_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            },
            "evaluation_0": {
                "eval_type": "binary"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "output_format": "dense"
                    }
                }
            },
            "host": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    }
                }
            }
        }
    }
}            
test_secureboost_train_binary_with_missing_value_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                },
                "use_missing": true
            },
            "evaluation_0": {
                "eval_type": "binary"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "ionosphere_scale_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "label_name": "label",
                        "label_type": "int",
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "label_name": "label",
                        "label_type": "int",
                        "output_format": "dense"
                    },
                    "reader_0": {
                        "table": {
                            "name": "ionosphere_scale_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "host": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "ionosphere_scale_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    },
                    "reader_0": {
                        "table": {
                            "name": "ionosphere_scale_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
test_secureboost_cross_validation_regression_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "regression",
                "objective_param": {
                    "objective": "lse"
                },
                "num_trees": 3,
                "cv_param": {
                    "need_cv": true,
                    "n_splits": 5,
                    "shuffle": false,
                    "random_seed": 103
                },
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            }
        },
        "role": {
            "host": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "student_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    }
                }
            },
            "guest": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "student_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "label_type": "float",
                        "output_format": "dense"
                    }
                }
            }
        }
    }
}            
test_secureboost_train_binary_cipher_compress_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "paillier"
                },
                "tree_param": {
                    "max_depth": 3
                },
                "cipher_compress_error": 8
            },
            "evaluation_0": {
                "eval_type": "binary"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "output_format": "dense"
                    }
                }
            },
            "host": {
                "0": {
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    }
                }
            }
        }
    }
}            
test_secureboost_cross_validation_dsl.json
{
    "components": {
        "reader_0": {
            "module": "Reader",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "data_transform_0": {
            "module": "DataTransform",
            "input": {
                "data": {
                    "data": [
                        "reader_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "intersection_0": {
            "module": "Intersection",
            "input": {
                "data": {
                    "data": [
                        "data_transform_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "hetero_secure_boost_0": {
            "module": "HeteroSecureBoost",
            "input": {
                "data": {
                    "train_data": [
                        "intersection_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        }
    }
}            
test_secureboost_train_complete_secure_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                },
                "complete_secure": true
            },
            "evaluation_0": {
                "eval_type": "binary"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "host": {
                "0": {
                    "data_transform_0": {
                        "with_label": false
                    },
                    "data_transform_1": {
                        "with_label": false
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "reader_1": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
test_secureboost_cross_validation_binary_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "cv_param": {
                    "need_cv": true,
                    "n_splits": 5,
                    "shuffle": false,
                    "random_seed": 103
                },
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            }
        },
        "role": {
            "guest": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    }
                }
            },
            "host": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_0": {
                        "with_label": false
                    }
                }
            }
        }
    }
}            
test_predict_dsl.json
{
    "components": {
        "reader_0": {
            "module": "Reader",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "intersection_0": {
            "input": {
                "data": {
                    "data": [
                        "data_transform_0.data"
                    ]
                }
            },
            "module": "Intersection",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "data_transform_0": {
            "input": {
                "data": {
                    "data": [
                        "reader_0.data"
                    ]
                },
                "model": [
                    "pipeline.data_transform_0.model"
                ]
            },
            "module": "DataTransform",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "hetero_secure_boost_0": {
            "input": {
                "data": {
                    "test_data": [
                        "intersection_0.data"
                    ]
                },
                "model": [
                    "pipeline.hetero_secure_boost_0.model"
                ]
            },
            "module": "HeteroSecureBoost",
            "output": {
                "data": [
                    "data"
                ]
            }
        }
    }
}            
test_secureboost_warm_start_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "arbiter": [
            9999
        ],
        "host": [
            10000
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "role": {
            "host": {
                "0": {
                    "data_transform_0": {
                        "with_label": false
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "guest": {
                "0": {
                    "data_transform_0": {
                        "with_label": true
                    },
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        },
        "common": {
            "data_transform_0": {
                "output_format": "dense"
            },
            "hetero_secure_boost_0": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            },
            "hetero_secure_boost_1": {
                "task_type": "classification",
                "objective_param": {
                    "objective": "cross_entropy"
                },
                "num_trees": 3,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                },
                "callback_param": {
                    "callbacks": [
                        "PerformanceEvaluate"
                    ],
                    "validation_freqs": 1
                }
            },
            "evaluation_0": {
                "eval_type": "binary"
            }
        }
    }
}            
test_secureboost_train_with_early_stopping_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "regression",
                "objective_param": {
                    "objective": "lse"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "early_stopping_rounds": 1,
                "tree_param": {
                    "max_depth": 3
                }
            },
            "evaluation_0": {
                "eval_type": "regression"
            }
        },
        "role": {
            "guest": {
                "0": {
                    "data_transform_1": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "data_transform_0": {
                        "with_label": true,
                        "output_format": "dense"
                    },
                    "reader_0": {
                        "table": {
                            "name": "student_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "reader_1": {
                        "table": {
                            "name": "student_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "host": {
                "0": {
                    "data_transform_1": {
                        "with_label": false
                    },
                    "data_transform_0": {
                        "with_label": false
                    },
                    "reader_0": {
                        "table": {
                            "name": "student_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "reader_1": {
                        "table": {
                            "name": "student_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
test_predict_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            10000
        ],
        "guest": [
            9999
        ]
    },
    "job_parameters": {
        "common": {
            "model_id": "guest-10000#host-9999#model",
            "model_version": "20200928174750711017114",
            "job_type": "predict"
        }
    },
    "component_parameters": {
        "role": {
            "guest": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "host": {
                "0": {
                    "reader_0": {
                        "table": {
                            "name": "breast_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
test_secureboost_train_regression_conf.json
{
    "dsl_version": 2,
    "initiator": {
        "role": "guest",
        "party_id": 9999
    },
    "role": {
        "host": [
            9998
        ],
        "guest": [
            9999
        ]
    },
    "component_parameters": {
        "common": {
            "hetero_secure_boost_0": {
                "task_type": "regression",
                "objective_param": {
                    "objective": "lse"
                },
                "num_trees": 3,
                "validation_freqs": 1,
                "encrypt_param": {
                    "method": "iterativeAffine"
                },
                "tree_param": {
                    "max_depth": 3
                }
            },
            "evaluation_0": {
                "eval_type": "regression"
            }
        },
        "role": {
            "host": {
                "0": {
                    "data_transform_0": {
                        "with_label": false
                    },
                    "reader_1": {
                        "table": {
                            "name": "student_hetero_host",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_1": {
                        "with_label": false
                    },
                    "reader_0": {
                        "table": {
                            "name": "student_hetero_host",
                            "namespace": "experiment"
                        }
                    }
                }
            },
            "guest": {
                "0": {
                    "data_transform_0": {
                        "with_label": true,
                        "label_type": "float",
                        "output_format": "dense"
                    },
                    "reader_1": {
                        "table": {
                            "name": "student_hetero_guest",
                            "namespace": "experiment"
                        }
                    },
                    "data_transform_1": {
                        "with_label": true,
                        "label_type": "float",
                        "output_format": "dense"
                    },
                    "reader_0": {
                        "table": {
                            "name": "student_hetero_guest",
                            "namespace": "experiment"
                        }
                    }
                }
            }
        }
    }
}            
hetero_secureboost_testsuite.json
{
    "data": [
        {
            "file": "examples/data/breast_hetero_guest.csv",
            "head": 1,
            "partition": 4,
            "table_name": "breast_hetero_guest",
            "namespace": "experiment",
            "role": "guest_0"
        },
        {
            "file": "examples/data/breast_hetero_host.csv",
            "head": 1,
            "partition": 4,
            "table_name": "breast_hetero_host",
            "namespace": "experiment",
            "role": "host_0"
        },
        {
            "file": "examples/data/vehicle_scale_hetero_guest.csv",
            "head": 1,
            "partition": 4,
            "table_name": "vehicle_scale_hetero_guest",
            "namespace": "experiment",
            "role": "guest_0"
        },
        {
            "file": "examples/data/vehicle_scale_hetero_host.csv",
            "head": 1,
            "partition": 4,
            "table_name": "vehicle_scale_hetero_host",
            "namespace": "experiment",
            "role": "host_0"
        },
        {
            "file": "examples/data/student_hetero_guest.csv",
            "head": 1,
            "partition": 4,
            "table_name": "student_hetero_guest",
            "namespace": "experiment",
            "role": "guest_0"
        },
        {
            "file": "examples/data/student_hetero_host.csv",
            "head": 1,
            "partition": 4,
            "table_name": "student_hetero_host",
            "namespace": "experiment",
            "role": "host_0"
        },
        {
            "file": "examples/data/ionosphere_scale_hetero_guest.csv",
            "head": 1,
            "partition": 4,
            "table_name": "ionosphere_scale_hetero_guest",
            "namespace": "experiment",
            "role": "guest_0"
        },
        {
            "file": "examples/data/ionosphere_scale_hetero_host.csv",
            "head": 1,
            "partition": 4,
            "table_name": "ionosphere_scale_hetero_host",
            "namespace": "experiment",
            "role": "host_0"
        },
        {
            "file": "examples/data/motor_hetero_guest.csv",
            "head": 1,
            "partition": 4,
            "table_name": "motor_hetero_guest",
            "namespace": "experiment",
            "role": "guest_0"
        },
        {
            "file": "examples/data/motor_hetero_host_1.csv",
            "head": 1,
            "partition": 4,
            "table_name": "motor_hetero_host_1",
            "namespace": "experiment",
            "role": "host_0"
        },
        {
            "file": "examples/data/motor_hetero_host_2.csv",
            "head": 1,
            "partition": 4,
            "table_name": "motor_hetero_host_2",
            "namespace": "experiment",
            "role": "host_1"
        }
    ],
    "tasks": {
        "train_binary": {
            "conf": "./test_secureboost_train_binary_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "warm_start_train": {
            "conf": "./test_secureboost_warm_start_conf.json",
            "dsl": "./test_secureboost_warm_start_dsl.json"
        },
        "train_complete_secure": {
            "conf": "./test_secureboost_train_complete_secure_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "train_binary_without_cipher_compress": {
            "conf": "./test_secureboost_train_binary_without_cipher_compress_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "train_binary_predict": {
            "conf": "./test_predict_conf.json",
            "dsl": "./test_predict_dsl.json",
            "deps": "train_binary"
        },
        "train_multi": {
            "conf": "./test_secureboost_train_multi_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "train_regression": {
            "conf": "./test_secureboost_train_regression_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "cv_binary": {
            "conf": "./test_secureboost_cross_validation_binary_conf.json",
            "dsl": "./test_secureboost_cross_validation_dsl.json"
        },
        "cv_multi": {
            "conf": "./test_secureboost_cross_validation_multi_conf.json",
            "dsl": "./test_secureboost_cross_validation_dsl.json"
        },
        "cv_regression": {
            "conf": "./test_secureboost_cross_validation_regression_conf.json",
            "dsl": "./test_secureboost_cross_validation_dsl.json"
        },
        "train_binary_with_missing_value": {
            "conf": "./test_secureboost_train_binary_with_missing_value_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "train_multi_host": {
            "conf": "./test_secureboost_train_regression_multi_host_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        },
        "train_with_early_stopping": {
            "conf": "./test_secureboost_train_with_early_stopping_conf.json",
            "dsl": "./test_secureboost_train_dsl.json"
        }
    }
}            
test_secureboost_train_dsl.json
{
    "components": {
        "reader_0": {
            "module": "Reader",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "reader_1": {
            "module": "Reader",
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "data_transform_0": {
            "module": "DataTransform",
            "input": {
                "data": {
                    "data": [
                        "reader_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "data_transform_1": {
            "module": "DataTransform",
            "input": {
                "data": {
                    "data": [
                        "reader_1.data"
                    ]
                },
                "model": [
                    "data_transform_0.model"
                ]
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "intersection_0": {
            "module": "Intersection",
            "input": {
                "data": {
                    "data": [
                        "data_transform_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "intersection_1": {
            "module": "Intersection",
            "input": {
                "data": {
                    "data": [
                        "data_transform_1.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ]
            }
        },
        "hetero_secure_boost_0": {
            "module": "HeteroSecureBoost",
            "input": {
                "data": {
                    "train_data": [
                        "intersection_0.data"
                    ],
                    "validate_data": [
                        "intersection_1.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ],
                "model": [
                    "model"
                ]
            }
        },
        "evaluation_0": {
            "module": "Evaluation",
            "input": {
                "data": {
                    "data": [
                        "hetero_secure_boost_0.data"
                    ]
                }
            },
            "output": {
                "data": [
                    "data"
                ]
            }
        }
    }
}            

Hetero Fast SecureBoost

We support Hetero Fast SecureBoost, in abbreviation, fast SBT, in FATE-1.5. The fast SBT uses guest features and host features alternately to build trees, in order to save encryption costs and communication costs. In fast SBT, we support MIX mode and LAYERED mode and they use different strategies while building decision trees.

MIX mode

In mix mode, we offer a new parameter 'tree_num_per_party'. Every participated party will build 'tree_num_per_party' trees using their local features, and this procedure will be repeated until reach the max tree number. Figure 5 illustrates the mix mode.

While building a guest tree, the guest party side simply computes g/h and finds the best split points, other host parties will skip this tree and wait. While building a host tree, the related host party will receive encrypted g/h and find the best split points with the assistant of the guest party. The structures of host trees and split points will be preserved on the host side while leaf weights will be preserved on the guest side. In this way, encryption and communication costs are reduced by half. (If there are two parties)

Figure 5: mix mode introduction

While conducting inference, every party will traverse its trees locally. All hosts will send the final leaf id to guests and the guest retrieves leaf weights using received leaf id. The prediction only needs one communication in mix mode.

Figure 6: mix mode training ('tree_num_per_party'=1) and predicting

LAYERED mode

In layered mode, only supports one guest party and one host party. The host will be responsible for building the first "host_depth" layers, with the help of the guest, and the guest will be responsible for the next "guest_depth" layers. All trees will be built in this 'layered' manner.

Figure 7: layered mode introduction

The benefits of layered mod is obvious, like the mix mode, parts of communication costs and encryption costs will be saved in the process of training. When predicting, we only need one communication because all host can conduct inferences of host layers locally.

Figure 8: layered mode training and predicting

According to experiments on our standard data sets, mix mode and layered mode of Fast SBT can still give performances (sometimes even better) equivalent to standard Hetero SecureBoost, even the training data is unbalanced distributed in different parties or contains noise features. (Binary, multi-class, and regression tasks are tested). At the same time, the time consumption of FAST SBT is reduced by 30% ~ 50% on average.

Optimization in learning

Fast SBT uses guest features and host features alternately by trees/layers to reduce encryption and communication costs.

  • Prediction only needs one communication round.

Applications

Fast SBT supports the following applications.

  • binary classification, the objective function is sigmoid cross-entropy
  • multi classification, the objective function is softmax cross-entropy
  • regression, objective function includes least-squared-error-loss、least-absolutely-error-loss、huber-loss、tweedie-loss、fair-loss、 log-cosh-loss

Other features

  • In mix mode, every host parties only keep their own tree models. Guest will only keep guest trees and host leaves.
  • In mix mode, host side support feature importance calculation (split type is supported, gain type is not supported)
  • In layered mode, model exporting setting is the same as the normal-SBT.
  • The time consumption of FAST SBT is reduced by 30% ~ 50% on average.

Last update: 2021-11-25
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