ML之CatboostC：基于titanic泰坦尼克数据集利用catboost算法实现二分类

痛定思痛。 2022-11-10 10:49 1571阅读 0赞

**目录**

基于titanic泰坦尼克数据集利用catboost算法实现二分类

设计思路

输出结果

核心代码

--------------------

**相关内容**  
[ML之CatBoost：CatBoost算法的简介、安装、案例应用之详细攻略][ML_CatBoost_CatBoost]  
[ML之CatboostC：基于titanic泰坦尼克数据集利用catboost算法实现二分类][ML_CatboostC_titanic_catboost]  
[ML之CatboostC：基于titanic泰坦尼克数据集利用catboost算法实现二分类实现][ML_CatboostC_titanic_catboost 1]

# 基于titanic泰坦尼克数据集利用catboost算法实现二分类 #

## 设计思路 ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMTg1ODY4_size_16_color_FFFFFF_t_70][]

## 输出结果 ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMTg1ODY4_size_16_color_FFFFFF_t_70 1][]

Pclass     Sex   Age  SibSp  Parch  Survived
    0       3    male  22.0      1      0         0
    1       1  female  38.0      1      0         1
    2       3  female  26.0      0      0         1
    3       1  female  35.0      1      0         1
    4       3    male  35.0      0      0         0
    Pclass        int64
    Sex          object
    Age         float64
    SibSp         int64
    Parch         int64
    Survived      int64
    dtype: object
    object_features_ID： [1]
    0:	learn: 0.5469469	test: 0.5358272	best: 0.5358272 (0)	total: 98.1ms	remaining: 9.71s
    1:	learn: 0.4884967	test: 0.4770551	best: 0.4770551 (1)	total: 98.7ms	remaining: 4.84s
    2:	learn: 0.4459496	test: 0.4453159	best: 0.4453159 (2)	total: 99.3ms	remaining: 3.21s
    3:	learn: 0.4331858	test: 0.4352757	best: 0.4352757 (3)	total: 99.8ms	remaining: 2.4s
    4:	learn: 0.4197131	test: 0.4266055	best: 0.4266055 (4)	total: 100ms	remaining: 1.91s
    5:	learn: 0.4085381	test: 0.4224953	best: 0.4224953 (5)	total: 101ms	remaining: 1.58s
    6:	learn: 0.4063807	test: 0.4209804	best: 0.4209804 (6)	total: 102ms	remaining: 1.35s
    7:	learn: 0.4007713	test: 0.4155077	best: 0.4155077 (7)	total: 102ms	remaining: 1.17s
    8:	learn: 0.3971064	test: 0.4135872	best: 0.4135872 (8)	total: 103ms	remaining: 1.04s
    9:	learn: 0.3943774	test: 0.4105674	best: 0.4105674 (9)	total: 103ms	remaining: 928ms
    10:	learn: 0.3930801	test: 0.4099915	best: 0.4099915 (10)	total: 104ms	remaining: 839ms
    11:	learn: 0.3904409	test: 0.4089840	best: 0.4089840 (11)	total: 104ms	remaining: 764ms
    12:	learn: 0.3890830	test: 0.4091666	best: 0.4089840 (11)	total: 105ms	remaining: 701ms
    13:	learn: 0.3851196	test: 0.4108839	best: 0.4089840 (11)	total: 105ms	remaining: 647ms
    14:	learn: 0.3833366	test: 0.4106298	best: 0.4089840 (11)	total: 106ms	remaining: 600ms
    15:	learn: 0.3792283	test: 0.4126097	best: 0.4089840 (11)	total: 106ms	remaining: 558ms
    16:	learn: 0.3765680	test: 0.4114997	best: 0.4089840 (11)	total: 107ms	remaining: 522ms
    17:	learn: 0.3760966	test: 0.4112166	best: 0.4089840 (11)	total: 107ms	remaining: 489ms
    18:	learn: 0.3736951	test: 0.4122305	best: 0.4089840 (11)	total: 108ms	remaining: 461ms
    19:	learn: 0.3719966	test: 0.4101199	best: 0.4089840 (11)	total: 109ms	remaining: 435ms
    20:	learn: 0.3711460	test: 0.4097299	best: 0.4089840 (11)	total: 109ms	remaining: 411ms
    21:	learn: 0.3707144	test: 0.4093512	best: 0.4089840 (11)	total: 110ms	remaining: 389ms
    22:	learn: 0.3699238	test: 0.4083409	best: 0.4083409 (22)	total: 110ms	remaining: 370ms
    23:	learn: 0.3670864	test: 0.4071850	best: 0.4071850 (23)	total: 111ms	remaining: 351ms
    24:	learn: 0.3635514	test: 0.4038399	best: 0.4038399 (24)	total: 111ms	remaining: 334ms
    25:	learn: 0.3627657	test: 0.4025837	best: 0.4025837 (25)	total: 112ms	remaining: 319ms
    26:	learn: 0.3621028	test: 0.4018449	best: 0.4018449 (26)	total: 113ms	remaining: 304ms
    27:	learn: 0.3616121	test: 0.4011693	best: 0.4011693 (27)	total: 113ms	remaining: 291ms
    28:	learn: 0.3614262	test: 0.4011820	best: 0.4011693 (27)	total: 114ms	remaining: 278ms
    29:	learn: 0.3610673	test: 0.4005475	best: 0.4005475 (29)	total: 114ms	remaining: 267ms
    30:	learn: 0.3588062	test: 0.4002801	best: 0.4002801 (30)	total: 115ms	remaining: 256ms
    31:	learn: 0.3583703	test: 0.3997255	best: 0.3997255 (31)	total: 116ms	remaining: 246ms
    32:	learn: 0.3580553	test: 0.4001878	best: 0.3997255 (31)	total: 116ms	remaining: 236ms
    33:	learn: 0.3556808	test: 0.4004169	best: 0.3997255 (31)	total: 118ms	remaining: 228ms
    34:	learn: 0.3536833	test: 0.4003229	best: 0.3997255 (31)	total: 119ms	remaining: 220ms
    35:	learn: 0.3519948	test: 0.4008047	best: 0.3997255 (31)	total: 119ms	remaining: 212ms
    36:	learn: 0.3515452	test: 0.4000576	best: 0.3997255 (31)	total: 120ms	remaining: 204ms
    37:	learn: 0.3512962	test: 0.3997214	best: 0.3997214 (37)	total: 120ms	remaining: 196ms
    38:	learn: 0.3507648	test: 0.4001569	best: 0.3997214 (37)	total: 121ms	remaining: 189ms
    39:	learn: 0.3489575	test: 0.4009203	best: 0.3997214 (37)	total: 121ms	remaining: 182ms
    40:	learn: 0.3480966	test: 0.4014031	best: 0.3997214 (37)	total: 122ms	remaining: 175ms
    41:	learn: 0.3477613	test: 0.4009293	best: 0.3997214 (37)	total: 122ms	remaining: 169ms
    42:	learn: 0.3472945	test: 0.4006602	best: 0.3997214 (37)	total: 123ms	remaining: 163ms
    43:	learn: 0.3465271	test: 0.4007531	best: 0.3997214 (37)	total: 124ms	remaining: 157ms
    44:	learn: 0.3461538	test: 0.4010608	best: 0.3997214 (37)	total: 124ms	remaining: 152ms
    45:	learn: 0.3455060	test: 0.4012489	best: 0.3997214 (37)	total: 125ms	remaining: 146ms
    46:	learn: 0.3449922	test: 0.4013439	best: 0.3997214 (37)	total: 125ms	remaining: 141ms
    47:	learn: 0.3445333	test: 0.4010754	best: 0.3997214 (37)	total: 126ms	remaining: 136ms
    48:	learn: 0.3443186	test: 0.4011180	best: 0.3997214 (37)	total: 126ms	remaining: 132ms
    49:	learn: 0.3424633	test: 0.4016071	best: 0.3997214 (37)	total: 127ms	remaining: 127ms
    50:	learn: 0.3421565	test: 0.4013135	best: 0.3997214 (37)	total: 128ms	remaining: 123ms
    51:	learn: 0.3417523	test: 0.4009993	best: 0.3997214 (37)	total: 128ms	remaining: 118ms
    52:	learn: 0.3415669	test: 0.4009101	best: 0.3997214 (37)	total: 129ms	remaining: 114ms
    53:	learn: 0.3413867	test: 0.4010833	best: 0.3997214 (37)	total: 130ms	remaining: 110ms
    54:	learn: 0.3405166	test: 0.4014830	best: 0.3997214 (37)	total: 130ms	remaining: 107ms
    55:	learn: 0.3401535	test: 0.4015556	best: 0.3997214 (37)	total: 131ms	remaining: 103ms
    56:	learn: 0.3395217	test: 0.4021097	best: 0.3997214 (37)	total: 132ms	remaining: 99.4ms
    57:	learn: 0.3393024	test: 0.4023377	best: 0.3997214 (37)	total: 132ms	remaining: 95.8ms
    58:	learn: 0.3389909	test: 0.4019616	best: 0.3997214 (37)	total: 133ms	remaining: 92.3ms
    59:	learn: 0.3388494	test: 0.4019746	best: 0.3997214 (37)	total: 133ms	remaining: 88.9ms
    60:	learn: 0.3384901	test: 0.4017470	best: 0.3997214 (37)	total: 134ms	remaining: 85.6ms
    61:	learn: 0.3382250	test: 0.4018783	best: 0.3997214 (37)	total: 134ms	remaining: 82.4ms
    62:	learn: 0.3345761	test: 0.4039633	best: 0.3997214 (37)	total: 135ms	remaining: 79.3ms
    63:	learn: 0.3317548	test: 0.4050218	best: 0.3997214 (37)	total: 136ms	remaining: 76.3ms
    64:	learn: 0.3306501	test: 0.4036656	best: 0.3997214 (37)	total: 136ms	remaining: 73.3ms
    65:	learn: 0.3292310	test: 0.4034339	best: 0.3997214 (37)	total: 137ms	remaining: 70.5ms
    66:	learn: 0.3283600	test: 0.4033661	best: 0.3997214 (37)	total: 137ms	remaining: 67.6ms
    67:	learn: 0.3282389	test: 0.4034237	best: 0.3997214 (37)	total: 138ms	remaining: 64.9ms
    68:	learn: 0.3274603	test: 0.4039310	best: 0.3997214 (37)	total: 138ms	remaining: 62.2ms
    69:	learn: 0.3273430	test: 0.4041663	best: 0.3997214 (37)	total: 139ms	remaining: 59.6ms
    70:	learn: 0.3271585	test: 0.4044144	best: 0.3997214 (37)	total: 140ms	remaining: 57.1ms
    71:	learn: 0.3268457	test: 0.4046981	best: 0.3997214 (37)	total: 140ms	remaining: 54.6ms
    72:	learn: 0.3266497	test: 0.4042724	best: 0.3997214 (37)	total: 141ms	remaining: 52.1ms
    73:	learn: 0.3259684	test: 0.4048797	best: 0.3997214 (37)	total: 141ms	remaining: 49.7ms
    74:	learn: 0.3257845	test: 0.4044766	best: 0.3997214 (37)	total: 142ms	remaining: 47.3ms
    75:	learn: 0.3256157	test: 0.4047031	best: 0.3997214 (37)	total: 143ms	remaining: 45.1ms
    76:	learn: 0.3251433	test: 0.4043698	best: 0.3997214 (37)	total: 144ms	remaining: 42.9ms
    77:	learn: 0.3247743	test: 0.4041652	best: 0.3997214 (37)	total: 144ms	remaining: 40.6ms
    78:	learn: 0.3224876	test: 0.4058880	best: 0.3997214 (37)	total: 145ms	remaining: 38.5ms
    79:	learn: 0.3223339	test: 0.4058139	best: 0.3997214 (37)	total: 145ms	remaining: 36.3ms
    80:	learn: 0.3211858	test: 0.4060056	best: 0.3997214 (37)	total: 146ms	remaining: 34.2ms
    81:	learn: 0.3200423	test: 0.4067103	best: 0.3997214 (37)	total: 147ms	remaining: 32.2ms
    82:	learn: 0.3198329	test: 0.4069039	best: 0.3997214 (37)	total: 147ms	remaining: 30.1ms
    83:	learn: 0.3196561	test: 0.4067853	best: 0.3997214 (37)	total: 148ms	remaining: 28.1ms
    84:	learn: 0.3193160	test: 0.4072288	best: 0.3997214 (37)	total: 148ms	remaining: 26.1ms
    85:	learn: 0.3184463	test: 0.4077451	best: 0.3997214 (37)	total: 149ms	remaining: 24.2ms
    86:	learn: 0.3175777	test: 0.4086243	best: 0.3997214 (37)	total: 149ms	remaining: 22.3ms
    87:	learn: 0.3173824	test: 0.4082013	best: 0.3997214 (37)	total: 150ms	remaining: 20.4ms
    88:	learn: 0.3172840	test: 0.4083946	best: 0.3997214 (37)	total: 150ms	remaining: 18.6ms
    89:	learn: 0.3166252	test: 0.4086761	best: 0.3997214 (37)	total: 151ms	remaining: 16.8ms
    90:	learn: 0.3164144	test: 0.4083237	best: 0.3997214 (37)	total: 151ms	remaining: 15ms
    91:	learn: 0.3162137	test: 0.4083699	best: 0.3997214 (37)	total: 152ms	remaining: 13.2ms
    92:	learn: 0.3155611	test: 0.4091627	best: 0.3997214 (37)	total: 152ms	remaining: 11.5ms
    93:	learn: 0.3153976	test: 0.4089484	best: 0.3997214 (37)	total: 153ms	remaining: 9.76ms
    94:	learn: 0.3139281	test: 0.4116939	best: 0.3997214 (37)	total: 154ms	remaining: 8.08ms
    95:	learn: 0.3128878	test: 0.4146652	best: 0.3997214 (37)	total: 154ms	remaining: 6.42ms
    96:	learn: 0.3127863	test: 0.4145767	best: 0.3997214 (37)	total: 155ms	remaining: 4.78ms
    97:	learn: 0.3126696	test: 0.4142118	best: 0.3997214 (37)	total: 155ms	remaining: 3.17ms
    98:	learn: 0.3120048	test: 0.4140831	best: 0.3997214 (37)	total: 156ms	remaining: 1.57ms
    99:	learn: 0.3117563	test: 0.4138267	best: 0.3997214 (37)	total: 156ms	remaining: 0us
    
    bestTest = 0.3997213503
    bestIteration = 37
    
    Shrink model to first 38 iterations.

## 核心代码 ##

class CatBoostClassifier Found at: catboost.core
    
    class CatBoostClassifier(CatBoost):
        _estimator_type = 'classifier'
        """
        Implementation of the scikit-learn API for CatBoost classification.
    
        Parameters
        ----------
        iterations : int, [default=500]
            Max count of trees.
            range: [1,+inf]
        learning_rate : float, [default value is selected automatically for 
         binary classification with other parameters set to default. In all 
         other cases default is 0.03]
            Step size shrinkage used in update to prevents overfitting.
            range: (0,1]
        depth : int, [default=6]
            Depth of a tree. All trees are the same depth.
            range: [1,+inf]
        l2_leaf_reg : float, [default=3.0]
            Coefficient at the L2 regularization term of the cost function.
            range: [0,+inf]
        model_size_reg : float, [default=None]
            Model size regularization coefficient.
            range: [0,+inf]
        rsm : float, [default=None]
            Subsample ratio of columns when constructing each tree.
            range: (0,1]
        loss_function : string or object, [default='Logloss']
            The metric to use in training and also selector of the machine 
             learning
            problem to solve. If string, then the name of a supported 
             metric,
            optionally suffixed with parameter description.
            If object, it shall provide methods 'calc_ders_range' or 
             'calc_ders_multi'.
        border_count : int, [default = 254 for training on CPU or 128 for 
         training on GPU]
            The number of partitions in numeric features binarization. 
             Used in the preliminary calculation.
            range: [1,65535] on CPU, [1,255] on GPU
        feature_border_type : string, [default='GreedyLogSum']
            The binarization mode in numeric features binarization. Used 
             in the preliminary calculation.
            Possible values:
                - 'Median'
                - 'Uniform'
                - 'UniformAndQuantiles'
                - 'GreedyLogSum'
                - 'MaxLogSum'
                - 'MinEntropy'
        per_float_feature_quantization : list of strings, [default=None]
            List of float binarization descriptions.
            Format : described in documentation on catboost.ai
            Example 1: ['0:1024'] means that feature 0 will have 1024 
             borders.
            Example 2: ['0:border_count=1024', '1:border_count=1024', 
             ...] means that two first features have 1024 borders.
            Example 3: ['0:nan_mode=Forbidden,border_count=32,
             border_type=GreedyLogSum',
                        '1:nan_mode=Forbidden,border_count=32,
                         border_type=GreedyLogSum'] - defines more quantization 
                         properties for first two features.
        input_borders : string, [default=None]
            input file with borders used in numeric features binarization.
        output_borders : string, [default=None]
            output file for borders that were used in numeric features 
             binarization.
        fold_permutation_block : int, [default=1]
            To accelerate the learning.
            The recommended value is within [1, 256]. On small samples, 
             must be set to 1.
            range: [1,+inf]
        od_pval : float, [default=None]
            Use overfitting detector to stop training when reaching a 
             specified threshold.
            Can be used only with eval_set.
            range: [0,1]
        od_wait : int, [default=None]
            Number of iterations which overfitting detector will wait after 
             new best error.
        od_type : string, [default=None]
            Type of overfitting detector which will be used in program.
            Posible values:
                - 'IncToDec'
                - 'Iter'
            For 'Iter' type od_pval must not be set.
            If None, then od_type=IncToDec.
        nan_mode : string, [default=None]
            Way to process missing values for numeric features.
            Possible values:
                - 'Forbidden' - raises an exception if there is a missing value 
                 for a numeric feature in a dataset.
                - 'Min' - each missing value will be processed as the 
                 minimum numerical value.
                - 'Max' - each missing value will be processed as the 
                 maximum numerical value.
            If None, then nan_mode=Min.
        counter_calc_method : string, [default=None]
            The method used to calculate counters for dataset with 
             Counter type.
            Possible values:
                - 'PrefixTest' - only objects up to current in the test dataset 
                 are considered
                - 'FullTest' - all objects are considered in the test dataset
                - 'SkipTest' - Objects from test dataset are not considered
                - 'Full' - all objects are considered for both learn and test 
                 dataset
            If None, then counter_calc_method=PrefixTest.
        leaf_estimation_iterations : int, [default=None]
            The number of steps in the gradient when calculating the 
             values in the leaves.
            If None, then leaf_estimation_iterations=1.
            range: [1,+inf]
        leaf_estimation_method : string, [default=None]
            The method used to calculate the values in the leaves.
            Possible values:
                - 'Newton'
                - 'Gradient'
        thread_count : int, [default=None]
            Number of parallel threads used to run CatBoost.
            If None or -1, then the number of threads is set to the 
             number of CPU cores.
            range: [1,+inf]
        random_seed : int, [default=None]
            Random number seed.
            If None, 0 is used.
            range: [0,+inf]
        use_best_model : bool, [default=None]
            To limit the number of trees in predict() using information 
             about the optimal value of the error function.
            Can be used only with eval_set.
        best_model_min_trees : int, [default=None]
            The minimal number of trees the best model should have.
        verbose: bool
            When set to True, logging_level is set to 'Verbose'.
            When set to False, logging_level is set to 'Silent'.
        silent: bool, synonym for verbose
        logging_level : string, [default='Verbose']
            Possible values:
                - 'Silent'
                - 'Verbose'
                - 'Info'
                - 'Debug'
        metric_period : int, [default=1]
            The frequency of iterations to print the information to stdout. 
             The value should be a positive integer.
        simple_ctr: list of strings, [default=None]
            Binarization settings for categorical features.
                Format : see documentation
                Example: ['Borders:CtrBorderCount=5:Prior=0:Prior=0.5', 
                 'BinarizedTargetMeanValue:TargetBorderCount=10:
                 TargetBorderType=MinEntropy', ...]
                CTR types:
                    CPU and GPU
                    - 'Borders'
                    - 'Buckets'
                    CPU only
                    - 'BinarizedTargetMeanValue'
                    - 'Counter'
                    GPU only
                    - 'FloatTargetMeanValue'
                    - 'FeatureFreq'
                Number_of_borders, binarization type, target borders and 
                 binarizations, priors are optional parametrs
        combinations_ctr: list of strings, [default=None]
        per_feature_ctr: list of strings, [default=None]
        ctr_target_border_count: int, [default=None]
            Maximum number of borders used in target binarization for 
             categorical features that need it.
            If TargetBorderCount is specified in 'simple_ctr', 
             'combinations_ctr' or 'per_feature_ctr' option it
            overrides this value.
            range: [1, 255]
        ctr_leaf_count_limit : int, [default=None]
            The maximum number of leaves with categorical features.
            If the number of leaves exceeds the specified limit, some 
             leaves are discarded.
            The leaves to be discarded are selected as follows:
                - The leaves are sorted by the frequency of the values.
                - The top N leaves are selected, where N is the value 
                 specified in the parameter.
                - All leaves starting from N+1 are discarded.
            This option reduces the resulting model size
            and the amount of memory required for training.
            Note that the resulting quality of the model can be affected.
            range: [1,+inf] (for zero limit use ignored_features)
        store_all_simple_ctr : bool, [default=None]
            Ignore categorical features, which are not used in feature 
             combinations,
            when choosing candidates for exclusion.
            Use this parameter with ctr_leaf_count_limit only.
        max_ctr_complexity : int, [default=4]
            The maximum number of Categ features that can be 
             combined.
            range: [0,+inf]
        has_time : bool, [default=False]
            To use the order in which objects are represented in the 
             input data
            (do not perform a random permutation of the dataset at the 
             preprocessing stage).
        allow_const_label : bool, [default=False]
            To allow the constant label value in dataset.
        target_border: float, [default=None]
            Border for target binarization.
        classes_count : int, [default=None]
            The upper limit for the numeric class label.
            Defines the number of classes for multiclassification.
            Only non-negative integers can be specified.
            The given integer should be greater than any of the target 
             values.
            If this parameter is specified the labels for all classes in the 
             input dataset
            should be smaller than the given value.
            If several of 'classes_count', 'class_weights', 'class_names' 
             parameters are defined
            the numbers of classes specified by each of them must be 
             equal.
        class_weights : list or dict, [default=None]
            Classes weights. The values are used as multipliers for the 
             object weights.
            If None, all classes are supposed to have weight one.
            If list - class weights in order of class_names or sequential 
             classes if class_names is undefined
            If dict - dict of class_name -> class_weight.
            If several of 'classes_count', 'class_weights', 'class_names' 
             parameters are defined
            the numbers of classes specified by each of them must be 
             equal.
        auto_class_weights : string [default=None]
            Enables automatic class weights calculation. Possible values:
                - Balanced  # weight = maxSummaryClassWeight / 
                 summaryClassWeight, statistics determined from train pool
                - SqrtBalanced  # weight = sqrt(maxSummaryClassWeight / 
                 summaryClassWeight)
        class_names: list of strings, [default=None]
            Class names. Allows to redefine the default values for class 
             labels (integer numbers).
            If several of 'classes_count', 'class_weights', 'class_names' 
             parameters are defined
            the numbers of classes specified by each of them must be 
             equal.
        one_hot_max_size : int, [default=None]
            Convert the feature to float
            if the number of different values that it takes exceeds the 
             specified value.
            Ctrs are not calculated for such features.
        random_strength : float, [default=1]
            Score standard deviation multiplier.
        name : string, [default='experiment']
            The name that should be displayed in the visualization tools.
        ignored_features : list, [default=None]
            Indices or names of features that should be excluded when 
             training.
        train_dir : string, [default=None]
            The directory in which you want to record generated in the 
             process of learning files.
        custom_metric : string or list of strings, [default=None]
            To use your own metric function.
        custom_loss: alias to custom_metric
        eval_metric : string or object, [default=None]
            To optimize your custom metric in loss.
        bagging_temperature : float, [default=None]
            Controls intensity of Bayesian bagging. The higher the 
             temperature the more aggressive bagging is.
            Typical values are in range [0, 1] (0 - no bagging, 1 - default).
        save_snapshot : bool, [default=None]
            Enable progress snapshotting for restoring progress after 
             crashes or interruptions
        snapshot_file : string, [default=None]
            Learn progress snapshot file path, if None will use default 
             filename
        snapshot_interval: int, [default=600]
            Interval between saving snapshots (seconds)
        fold_len_multiplier : float, [default=None]
            Fold length multiplier. Should be greater than 1
        used_ram_limit : string or number, [default=None]
            Set a limit on memory consumption (value like '1.2gb' or 1.2
             e9).
            WARNING: Currently this option affects CTR memory usage 
             only.
        gpu_ram_part : float, [default=0.95]
            Fraction of the GPU RAM to use for training, a value from (0, 
             1].
        pinned_memory_size: int [default=None]
            Size of additional CPU pinned memory used for GPU learning,
            usually is estimated automatically, thus usually should not be 
             set.
        allow_writing_files : bool, [default=True]
            If this flag is set to False, no files with different diagnostic info 
             will be created during training.
            With this flag no snapshotting can be done. Plus visualisation 
             will not
            work, because visualisation uses files that are created and 
             updated during training.
        final_ctr_computation_mode : string, [default='Default']
            Possible values:
                - 'Default' - Compute final ctrs for all pools.
                - 'Skip' - Skip final ctr computation. WARNING: model 
                 without ctrs can't be applied.
        approx_on_full_history : bool, [default=False]
            If this flag is set to True, each approximated value is 
             calculated using all the preceeding rows in the fold (slower, more 
             accurate).
            If this flag is set to False, each approximated value is 
             calculated using only the beginning 1/fold_len_multiplier fraction 
             of the fold (faster, slightly less accurate).
        boosting_type : string, default value depends on object count 
         and feature count in train dataset and on learning mode.
            Boosting scheme.
            Possible values:
                - 'Ordered' - Gives better quality, but may slow down the 
                 training.
                - 'Plain' - The classic gradient boosting scheme. May result 
                 in quality degradation, but does not slow down the training.
        task_type : string, [default=None]
            The calcer type used to train the model.
            Possible values:
                - 'CPU'
                - 'GPU'
        device_config : string, [default=None], deprecated, use devices 
         instead
        devices : list or string, [default=None], GPU devices to use.
            String format is: '0' for 1 device or '0:1:3' for multiple devices 
             or '0-3' for range of devices.
            List format is : [0] for 1 device or [0,1,3] for multiple devices.
    
        bootstrap_type : string, Bayesian, Bernoulli, Poisson, MVS.
            Default bootstrap is Bayesian for GPU and MVS for CPU.
            Poisson bootstrap is supported only on GPU.
            MVS bootstrap is supported only on CPU.
    
        subsample : float, [default=None]
            Sample rate for bagging. This parameter can be used Poisson 
             or Bernoully bootstrap types.
    
        mvs-reg : float, [default is set automatically at each iteration 
         based on gradient distribution]
            Regularization parameter for MVS sampling algorithm
    
        monotone_constraints : list or numpy.ndarray or string or dict, 
         [default=None]
            Monotone constraints for features.
    
        feature_weights : list or numpy.ndarray or string or dict, 
         [default=None]
            Coefficient to multiply split gain with specific feature use. 
             Should be non-negative.
    
        penalties_coefficient : float, [default=1]
            Common coefficient for all penalties. Should be non-negative.
    
        first_feature_use_penalties : list or numpy.ndarray or string or 
         dict, [default=None]
            Penalties to first use of specific feature in model. Should be 
             non-negative.
    
        per_object_feature_penalties : list or numpy.ndarray or string or 
         dict, [default=None]
            Penalties for first use of feature for each object. Should be 
             non-negative.
    
        sampling_frequency : string, [default=PerTree]
            Frequency to sample weights and objects when building 
             trees.
            Possible values:
                - 'PerTree' - Before constructing each new tree
                - 'PerTreeLevel' - Before choosing each new split of a tree
    
        sampling_unit : string, [default='Object'].
            Possible values:
                - 'Object'
                - 'Group'
            The parameter allows to specify the sampling scheme:
            sample weights for each object individually or for an entire 
             group of objects together.
    
        dev_score_calc_obj_block_size: int, [default=5000000]
            CPU only. Size of block of samples in score calculation. Should 
             be > 0
            Used only for learning speed tuning.
            Changing this parameter can affect results due to numerical 
             accuracy differences
    
        dev_efb_max_buckets : int, [default=1024]
            CPU only. Maximum bucket count in exclusive features 
             bundle. Should be in an integer between 0 and 65536.
            Used only for learning speed tuning.
    
        sparse_features_conflict_fraction : float, [default=0.0]
            CPU only. Maximum allowed fraction of conflicting non-
             default values for features in exclusive features bundle.
            Should be a real value in [0, 1) interval.
    
        grow_policy : string, [SymmetricTree,Lossguide,Depthwise], 
         [default=SymmetricTree]
            The tree growing policy. It describes how to perform greedy 
             tree construction.
    
        min_data_in_leaf : int, [default=1].
            The minimum training samples count in leaf.
            CatBoost will not search for new splits in leaves with samples 
             count less than min_data_in_leaf.
            This parameter is used only for Depthwise and Lossguide 
             growing policies.
    
        max_leaves : int, [default=31],
            The maximum leaf count in resulting tree.
            This parameter is used only for Lossguide growing policy.
    
        score_function : string, possible values L2, Cosine, NewtonL2, 
         NewtonCosine, [default=Cosine]
            For growing policy Lossguide default=NewtonL2.
            GPU only. Score that is used during tree construction to 
             select the next tree split.
    
        max_depth : int, Synonym for depth.
    
        n_estimators : int, synonym for iterations.
    
        num_trees : int, synonym for iterations.
    
        num_boost_round : int, synonym for iterations.
    
        colsample_bylevel : float, synonym for rsm.
    
        random_state : int, synonym for random_seed.
    
        reg_lambda : float, synonym for l2_leaf_reg.
    
        objective : string, synonym for loss_function.
    
        num_leaves : int, synonym for max_leaves.
    
        min_child_samples : int, synonym for min_data_in_leaf
    
        eta : float, synonym for learning_rate.
    
        max_bin : float, synonym for border_count.
    
        scale_pos_weight : float, synonym for class_weights.
            Can be used only for binary classification. Sets weight 
             multiplier for
            class 1 to scale_pos_weight value.
    
        metadata : dict, string to string key-value pairs to be stored in 
         model metadata storage
    
        early_stopping_rounds : int
            Synonym for od_wait. Only one of these parameters should 
             be set.
    
        cat_features : list or numpy.ndarray, [default=None]
            If not None, giving the list of Categ features indices or names 
             (names are represented as strings).
            If it contains feature names, feature names must be defined 
             for the training dataset passed to 'fit'.
    
        text_features : list or numpy.ndarray, [default=None]
            If not None, giving the list of Text features indices or names 
             (names are represented as strings).
            If it contains feature names, feature names must be defined 
             for the training dataset passed to 'fit'.
    
        embedding_features : list or numpy.ndarray, [default=None]
            If not None, giving the list of Embedding features indices or 
             names (names are represented as strings).
            If it contains feature names, feature names must be defined 
             for the training dataset passed to 'fit'.
    
        leaf_estimation_backtracking : string, [default=None]
            Type of backtracking during gradient descent.
            Possible values:
                - 'No' - never backtrack; supported on CPU and GPU
                - 'AnyImprovement' - reduce the descent step until the 
                 value of loss function is less than before the step; supported on 
                 CPU and GPU
                - 'Armijo' - reduce the descent step until Armijo condition 
                 is satisfied; supported on GPU only
    
        model_shrink_rate : float, [default=0]
            This parameter enables shrinkage of model at the start of 
             each iteration. CPU only.
            For Constant mode shrinkage coefficient is calculated as (1 - 
             model_shrink_rate * learning_rate).
            For Decreasing mode shrinkage coefficient is calculated as (1 
             - model_shrink_rate / iteration).
            Shrinkage coefficient should be in [0, 1).
    
        model_shrink_mode : string, [default=None]
            Mode of shrinkage coefficient calculation. CPU only.
            Possible values:
                - 'Constant' - Shrinkage coefficient is constant at each 
                 iteration.
                - 'Decreasing' - Shrinkage coefficient decreases at each 
                 iteration.
    
        langevin : bool, [default=False]
            Enables the Stochastic Gradient Langevin Boosting. CPU only.
    
        diffusion_temperature : float, [default=0]
            Langevin boosting diffusion temperature. CPU only.
    
        posterior_sampling : bool, [default=False]
            Set group of parameters for further use Uncertainty 
             prediction:
                - Langevin = True
                - Model Shrink Rate = 1/(2N), where N is dataset size
                - Model Shrink Mode = Constant
                - Diffusion-temperature = N, where N is dataset size. CPU 
                 only.
    
        boost_from_average : bool, [default=True for RMSE, False for 
         other losses]
            Enables to initialize approx values by best constant value for 
             specified loss function.
            Available for RMSE, Logloss, CrossEntropy, Quantile and MAE.
    
        tokenizers : list of dicts,
            Each dict is a tokenizer description. Example:
            ```
            [
                {
                    'tokenizer_id': 'Tokenizer',  # Tokeinzer identifier.
                    'lowercasing': 'false',  # Possible values: 'true', 'false'.
                    'number_process_policy': 'LeaveAsIs',  # Possible values: 
                     'Skip', 'LeaveAsIs', 'Replace'.
                    'number_token': '%',  # Rarely used character. Used in 
                     conjunction with Replace NumberProcessPolicy.
                    'separator_type': 'ByDelimiter',  # Possible values: 
                     'ByDelimiter', 'BySense'.
                    'delimiter': ' ',  # Used in conjunction with ByDelimiter 
                     SeparatorType.
                    'split_by_set': 'false',  # Each single character in delimiter 
                     used as individual delimiter.
                    'skip_empty': 'true',  # Possible values: 'true', 'false'.
                    'token_types': ['Word', 'Number', 'Unknown'],  # Used in 
                     conjunction with BySense SeparatorType.
                        # Possible values: 'Word', 'Number', 'Punctuation', 
                         'SentenceBreak', 'ParagraphBreak', 'Unknown'.
                    'subtokens_policy': 'SingleToken',  # Possible values:
                        # 'SingleToken' - All subtokens are interpreted as 
                         single token).
                        # 'SeveralTokens' - All subtokens are interpreted as 
                         several token.
                },
                ...
            ]
            ```
    
        dictionaries : list of dicts,
            Each dict is a tokenizer description. Example:
            ```
            [
                {
                    'dictionary_id': 'Dictionary',  # Dictionary identifier.
                    'token_level_type': 'Word',  # Possible values: 'Word', 
                     'Letter'.
                    'gram_order': '1',  # 1 for Unigram, 2 for Bigram, ...
                    'skip_step': '0',  # 1 for 1-skip-gram, ...
                    'end_of_word_token_policy': 'Insert',  # Possible values: 
                     'Insert', 'Skip'.
                    'end_of_sentence_token_policy': 'Skip',  # Possible values: 
                     'Insert', 'Skip'.
                    'occurrence_lower_bound': '3',  # The lower bound of 
                     token occurrences in the text to include it in the dictionary.
                    'max_dictionary_size': '50000',  # The max dictionary size.
                },
                ...
            ]
            ```
    
        feature_calcers : list of strings,
            Each string is a calcer description. Example:
            ```
            [
                'NaiveBayes',
                'BM25',
                'BoW:top_tokens_count=2000',
            ]
            ```
    
        text_processing : dict,
            Text processging description.
        """
        def __init__(
            self, 
            iterations=None, 
            learning_rate=None, 
            depth=None, 
            l2_leaf_reg=None, 
            model_size_reg=None, 
            rsm=None, 
            loss_function=None, 
            border_count=None, 
            feature_border_type=None, 
            per_float_feature_quantization=None, 
            input_borders=None, 
            output_borders=None, 
            fold_permutation_block=None, 
            od_pval=None, 
            od_wait=None, 
            od_type=None, 
            nan_mode=None, 
            counter_calc_method=None, 
            leaf_estimation_iterations=None, 
            leaf_estimation_method=None, 
            thread_count=None, 
            random_seed=None, 
            use_best_model=None, 
            best_model_min_trees=None, 
            verbose=None, 
            silent=None, 
            logging_level=None, 
            metric_period=None, 
            ctr_leaf_count_limit=None, 
            store_all_simple_ctr=None, 
            max_ctr_complexity=None, 
            has_time=None, 
            allow_const_label=None, 
            target_border=None, 
            classes_count=None, 
            class_weights=None, 
            auto_class_weights=None, 
            class_names=None, 
            one_hot_max_size=None, 
            random_strength=None, 
            name=None, 
            ignored_features=None, 
            train_dir=None, 
            custom_loss=None, 
            custom_metric=None, 
            eval_metric=None, 
            bagging_temperature=None, 
            save_snapshot=None, 
            snapshot_file=None, 
            snapshot_interval=None, 
            fold_len_multiplier=None, 
            used_ram_limit=None, 
            gpu_ram_part=None, 
            pinned_memory_size=None, 
            allow_writing_files=None, 
            final_ctr_computation_mode=None, 
            approx_on_full_history=None, 
            boosting_type=None, 
            simple_ctr=None, 
            combinations_ctr=None, 
            per_feature_ctr=None, 
            ctr_description=None, 
            ctr_target_border_count=None, 
            task_type=None, 
            device_config=None, 
            devices=None, 
            bootstrap_type=None, 
            subsample=None, 
            mvs_reg=None, 
            sampling_unit=None, 
            sampling_frequency=None, 
            dev_score_calc_obj_block_size=None, 
            dev_efb_max_buckets=None, 
            sparse_features_conflict_fraction=None, 
            max_depth=None, 
            n_estimators=None, 
            num_boost_round=None, 
            num_trees=None, 
            colsample_bylevel=None, 
            random_state=None, 
            reg_lambda=None, 
            objective=None, 
            eta=None, 
            max_bin=None, 
            scale_pos_weight=None, 
            gpu_cat_features_storage=None, 
            data_partition=None, 
            metadata=None, 
            early_stopping_rounds=None, 
            cat_features=None, 
            grow_policy=None, 
            min_data_in_leaf=None, 
            min_child_samples=None, 
            max_leaves=None, 
            num_leaves=None, 
            score_function=None, 
            leaf_estimation_backtracking=None, 
            ctr_history_unit=None, 
            monotone_constraints=None, 
            feature_weights=None, 
            penalties_coefficient=None, 
            first_feature_use_penalties=None, 
            per_object_feature_penalties=None, 
            model_shrink_rate=None, 
            model_shrink_mode=None, 
            langevin=None, 
            diffusion_temperature=None, 
            posterior_sampling=None, 
            boost_from_average=None, 
            text_features=None, 
            tokenizers=None, 
            dictionaries=None, 
            feature_calcers=None, 
            text_processing=None, 
            embedding_features=None):
            params = {}
            not_params = ["not_params", "self", "params", "__class__"]
            for key, value in iteritems(locals().copy()):
                if key not in not_params and value is not None:
                    params[key] = value
            
            super(CatBoostClassifier, self).__init__(params)
        
        def fit(self, X, y=None, cat_features=None, text_features=None, 
         embedding_features=None, sample_weight=None, 
         baseline=None, use_best_model=None, 
            eval_set=None, verbose=None, logging_level=None, 
             plot=False, column_description=None, 
            verbose_eval=None, metric_period=None, silent=None, 
             early_stopping_rounds=None, 
            save_snapshot=None, snapshot_file=None, 
             snapshot_interval=None, init_model=None):
            """
            Fit the CatBoostClassifier model.
    
            Parameters
            ----------
            X : catboost.Pool or list or numpy.ndarray or pandas.
             DataFrame or pandas.Series
                If not catboost.Pool, 2 dimensional Feature matrix or string 
                 - file with dataset.
    
            y : list or numpy.ndarray or pandas.DataFrame or pandas.
             Series, optional (default=None)
                Labels, 1 dimensional array like.
                Use only if X is not catboost.Pool.
    
            cat_features : list or numpy.ndarray, optional (default=None)
                If not None, giving the list of Categ columns indices.
                Use only if X is not catboost.Pool.
    
            text_features : list or numpy.ndarray, optional (default=None)
                If not None, giving the list of Text columns indices.
                Use only if X is not catboost.Pool.
    
            embedding_features : list or numpy.ndarray, optional 
             (default=None)
                If not None, giving the list of Embedding columns indices.
                Use only if X is not catboost.Pool.
    
            sample_weight : list or numpy.ndarray or pandas.DataFrame 
             or pandas.Series, optional (default=None)
                Instance weights, 1 dimensional array like.
    
            baseline : list or numpy.ndarray, optional (default=None)
                If not None, giving 2 dimensional array like data.
                Use only if X is not catboost.Pool.
    
            use_best_model : bool, optional (default=None)
                Flag to use best model
    
            eval_set : catboost.Pool or list, optional (default=None)
                A list of (X, y) tuple pairs to use as a validation set for early-
                 stopping
    
            metric_period : int
                Frequency of evaluating metrics.
    
            verbose : bool or int
                If verbose is bool, then if set to True, logging_level is set to 
                 Verbose,
                if set to False, logging_level is set to Silent.
                If verbose is int, it determines the frequency of writing 
                 metrics to output and
                logging_level is set to Verbose.
    
            silent : bool
                If silent is True, logging_level is set to Silent.
                If silent is False, logging_level is set to Verbose.
    
            logging_level : string, optional (default=None)
                Possible values:
                    - 'Silent'
                    - 'Verbose'
                    - 'Info'
                    - 'Debug'
    
            plot : bool, optional (default=False)
                If True, draw train and eval error in Jupyter notebook
    
            verbose_eval : bool or int
                Synonym for verbose. Only one of these parameters should 
                 be set.
    
            early_stopping_rounds : int
                Activates Iter overfitting detector with od_wait set to 
                 early_stopping_rounds.
    
            save_snapshot : bool, [default=None]
                Enable progress snapshotting for restoring progress after 
                 crashes or interruptions
    
            snapshot_file : string, [default=None]
                Learn progress snapshot file path, if None will use default 
                 filename
    
            snapshot_interval: int, [default=600]
                Interval between saving snapshots (seconds)
    
            init_model : CatBoost class or string, [default=None]
                Continue training starting from the existing model.
                If this parameter is a string, load initial model from the path 
                 specified by this string.
    
            Returns
            -------
            model : CatBoost
            """
            params = self._init_params.copy()
            _process_synonyms(params)
            if 'loss_function' in params:
                self._check_is_classification_objective(params
                 ['loss_function'])
            self._fit(X, y, cat_features, text_features, embedding_features, 
             None, sample_weight, None, None, None, None, baseline, 
             use_best_model, eval_set, verbose, logging_level, plot, 
             column_description, verbose_eval, metric_period, silent, 
             early_stopping_rounds, save_snapshot, snapshot_file, 
             snapshot_interval, init_model)
            return self
        
        def predict(self, data, prediction_type='Class', ntree_start=0, 
         ntree_end=0, thread_count=-1, verbose=None):
            """
            Predict with data.
    
            Parameters
            ----------
            data : catboost.Pool or list of features or list of lists or numpy.
             ndarray or pandas.DataFrame or pandas.Series
                    or catboost.FeaturesData
                Data to apply model on.
                If data is a simple list (not list of lists) or a one-dimensional 
                 numpy.ndarray it is interpreted
                as a list of features for a single object.
    
            prediction_type : string, optional (default='Class')
                Can be:
                - 'RawFormulaVal' : return raw formula value.
                - 'Class' : return class label.
                - 'Probability' : return probability for every class.
                - 'LogProbability' : return log probability for every class.
    
            ntree_start: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 (zero-based indexing).
    
            ntree_end: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 (zero-based indexing).
                If value equals to 0 this parameter is ignored and ntree_end 
                 equal to tree_count_.
    
            thread_count : int (default=-1)
                The number of threads to use when applying the model.
                Allows you to optimize the speed of execution. This 
                 parameter doesn't affect results.
                If -1, then the number of threads is set to the number of 
                 CPU cores.
    
            verbose : bool, optional (default=False)
                If True, writes the evaluation metric measured set to stderr.
    
            Returns
            -------
            prediction:
                If data is for a single object, the return value depends on 
                 prediction_type value:
                    - 'RawFormulaVal' : return raw formula value.
                    - 'Class' : return class label.
                    - 'Probability' : return one-dimensional numpy.ndarray 
                     with probability for every class.
                    - 'LogProbability' : return one-dimensional numpy.
                     ndarray with
                      log probability for every class.
                otherwise numpy.ndarray, with values that depend on 
                 prediction_type value:
                    - 'RawFormulaVal' : one-dimensional array of raw formula 
                     value for each object.
                    - 'Class' : one-dimensional array of class label for each 
                     object.
                    - 'Probability' : two-dimensional numpy.ndarray with 
                     shape (number_of_objects x number_of_classes)
                      with probability for every class for each object.
                    - 'LogProbability' : two-dimensional numpy.ndarray with 
                     shape (number_of_objects x number_of_classes)
                      with log probability for every class for each object.
            """
            return self._predict(data, prediction_type, ntree_start, 
             ntree_end, thread_count, verbose, 'predict')
        
        def predict_proba(self, data, ntree_start=0, ntree_end=0, 
         thread_count=-1, verbose=None):
            """
            Predict class probability with data.
    
            Parameters
            ----------
            data : catboost.Pool or list of features or list of lists or numpy.
             ndarray or pandas.DataFrame or pandas.Series
                    or catboost.FeaturesData
                Data to apply model on.
                If data is a simple list (not list of lists) or a one-dimensional 
                 numpy.ndarray it is interpreted
                as a list of features for a single object.
    
            ntree_start: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 (zero-based indexing).
    
            ntree_end: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 (zero-based indexing).
                If value equals to 0 this parameter is ignored and ntree_end 
                 equal to tree_count_.
    
            thread_count : int (default=-1)
                The number of threads to use when applying the model.
                Allows you to optimize the speed of execution. This 
                 parameter doesn't affect results.
                If -1, then the number of threads is set to the number of 
                 CPU cores.
    
            verbose : bool
                If True, writes the evaluation metric measured set to stderr.
    
            Returns
            -------
            prediction :
                If data is for a single object
                    return one-dimensional numpy.ndarray with probability 
                     for every class.
                otherwise
                    return two-dimensional numpy.ndarray with shape 
                     (number_of_objects x number_of_classes)
                    with probability for every class for each object.
            """
            return self._predict(data, 'Probability', ntree_start, ntree_end, 
             thread_count, verbose, 'predict_proba')
        
        def predict_log_proba(self, data, ntree_start=0, ntree_end=0, 
         thread_count=-1, verbose=None):
            """
            Predict class log probability with data.
    
            Parameters
            ----------
            data : catboost.Pool or list of features or list of lists or numpy.
             ndarray or pandas.DataFrame or pandas.Series
                    or catboost.FeaturesData
                Data to apply model on.
                If data is a simple list (not list of lists) or a one-dimensional 
                 numpy.ndarray it is interpreted
                as a list of features for a single object.
    
            ntree_start: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 (zero-based indexing).
    
            ntree_end: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 (zero-based indexing).
                If value equals to 0 this parameter is ignored and ntree_end 
                 equal to tree_count_.
    
            thread_count : int (default=-1)
                The number of threads to use when applying the model.
                Allows you to optimize the speed of execution. This 
                 parameter doesn't affect results.
                If -1, then the number of threads is set to the number of 
                 CPU cores.
    
            verbose : bool
                If True, writes the evaluation metric measured set to stderr.
    
            Returns
            -------
            prediction :
                If data is for a single object
                    return one-dimensional numpy.ndarray with log 
                     probability for every class.
                otherwise
                    return two-dimensional numpy.ndarray with shape 
                     (number_of_objects x number_of_classes)
                    with log probability for every class for each object.
            """
            return self._predict(data, 'LogProbability', ntree_start, 
             ntree_end, thread_count, verbose, 'predict_log_proba')
        
        def staged_predict(self, data, prediction_type='Class', 
         ntree_start=0, ntree_end=0, eval_period=1, thread_count=-1, 
         verbose=None):
            """
            Predict target at each stage for data.
    
            Parameters
            ----------
            data : catboost.Pool or list of features or list of lists or numpy.
             ndarray or pandas.DataFrame or pandas.Series
                    or catboost.FeaturesData
                Data to apply model on.
                If data is a simple list (not list of lists) or a one-dimensional 
                 numpy.ndarray it is interpreted
                as a list of features for a single object.
    
            prediction_type : string, optional (default='Class')
                Can be:
                - 'RawFormulaVal' : return raw formula value.
                - 'Class' : return class label.
                - 'Probability' : return probability for every class.
                - 'LogProbability' : return log probability for every class.
    
            ntree_start: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
    
            ntree_end: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
                If value equals to 0 this parameter is ignored and ntree_end 
                 equal to tree_count_.
    
            eval_period: int, optional (default=1)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
    
            thread_count : int (default=-1)
                The number of threads to use when applying the model.
                Allows you to optimize the speed of execution. This 
                 parameter doesn't affect results.
                If -1, then the number of threads is set to the number of 
                 CPU cores.
    
            verbose : bool
                If True, writes the evaluation metric measured set to stderr.
    
            Returns
            -------
            prediction : generator for each iteration that generates:
                If data is for a single object, the return value depends on 
                 prediction_type value:
                    - 'RawFormulaVal' : return raw formula value.
                    - 'Class' : return majority vote class.
                    - 'Probability' : return one-dimensional numpy.ndarray 
                     with probability for every class.
                    - 'LogProbability' : return one-dimensional numpy.
                     ndarray with
                      log probability for every class.
                otherwise numpy.ndarray, with values that depend on 
                 prediction_type value:
                    - 'RawFormulaVal' : one-dimensional array of raw formula 
                     value for each object.
                    - 'Class' : one-dimensional array of class label for each 
                     object.
                    - 'Probability' : two-dimensional numpy.ndarray with 
                     shape (number_of_objects x number_of_classes)
                      with probability for every class for each object.
                    - 'LogProbability' : two-dimensional numpy.ndarray with 
                     shape (number_of_objects x number_of_classes)
                      with log probability for every class for each object.
            """
            return self._staged_predict(data, prediction_type, ntree_start, 
             ntree_end, eval_period, thread_count, verbose, 'staged_predict')
        
        def staged_predict_proba(self, data, ntree_start=0, 
         ntree_end=0, eval_period=1, thread_count=-1, verbose=None):
            """
            Predict classification target at each stage for data.
    
            Parameters
            ----------
            data : catboost.Pool or list of features or list of lists or numpy.
             ndarray or pandas.DataFrame or pandas.Series
                    or catboost.FeaturesData
                Data to apply model on.
                If data is a simple list (not list of lists) or a one-dimensional 
                 numpy.ndarray it is interpreted
                as a list of features for a single object.
    
            ntree_start: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
    
            ntree_end: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
                If value equals to 0 this parameter is ignored and ntree_end 
                 equal to tree_count_.
    
            eval_period: int, optional (default=1)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
    
            thread_count : int (default=-1)
                The number of threads to use when applying the model.
                Allows you to optimize the speed of execution. This 
                 parameter doesn't affect results.
                If -1, then the number of threads is set to the number of 
                 CPU cores.
    
            verbose : bool
                If True, writes the evaluation metric measured set to stderr.
    
            Returns
            -------
            prediction : generator for each iteration that generates:
                If data is for a single object
                    return one-dimensional numpy.ndarray with probability 
                     for every class.
                otherwise
                    return two-dimensional numpy.ndarray with shape 
                     (number_of_objects x number_of_classes)
                    with probability for every class for each object.
            """
            return self._staged_predict(data, 'Probability', ntree_start, 
             ntree_end, eval_period, thread_count, verbose, 
             'staged_predict_proba')
        
        def staged_predict_log_proba(self, data, ntree_start=0, 
         ntree_end=0, eval_period=1, thread_count=-1, verbose=None):
            """
            Predict classification target at each stage for data.
    
            Parameters
            ----------
            data : catboost.Pool or list of features or list of lists or numpy.
             ndarray or pandas.DataFrame or pandas.Series
                    or catboost.FeaturesData
                Data to apply model on.
                If data is a simple list (not list of lists) or a one-dimensional 
                 numpy.ndarray it is interpreted
                as a list of features for a single object.
    
            ntree_start: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
    
            ntree_end: int, optional (default=0)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
                If value equals to 0 this parameter is ignored and ntree_end 
                 equal to tree_count_.
    
            eval_period: int, optional (default=1)
                Model is applied on the interval [ntree_start, ntree_end) 
                 with the step eval_period (zero-based indexing).
    
            thread_count : int (default=-1)
                The number of threads to use when applying the model.
                Allows you to optimize the speed of execution. This 
                 parameter doesn't affect results.
                If -1, then the number of threads is set to the number of 
                 CPU cores.
    
            verbose : bool
                If True, writes the evaluation metric measured set to stderr.
    
            Returns
            -------
            prediction : generator for each iteration that generates:
                If data is for a single object
                    return one-dimensional numpy.ndarray with log 
                     probability for every class.
                otherwise
                    return two-dimensional numpy.ndarray with shape 
                     (number_of_objects x number_of_classes)
                    with log probability for every class for each object.
            """
            return self._staged_predict(data, 'LogProbability', ntree_start, 
             ntree_end, eval_period, thread_count, verbose, 
             'staged_predict_log_proba')
        
        def score(self, X, y=None):
            """
            Calculate accuracy.
    
            Parameters
            ----------
            X : catboost.Pool or list or numpy.ndarray or pandas.
             DataFrame or pandas.Series
                Data to apply model on.
            y : list or numpy.ndarray
                True labels.
    
            Returns
            -------
            accuracy : float
            """
            if isinstance(X, Pool):
                if y is not None:
                    raise CatBoostError("Wrong initializing y: X is catboost.
                     Pool object, y must be initialized inside catboost.Pool.")
                y = X.get_label()
                if y is None:
                    raise CatBoostError("Label in X has not initialized.")
            if isinstance(y, DataFrame):
                if len(y.columns) != 1:
                    raise CatBoostError("y is DataFrame and has {} columns, 
                     but must have exactly one.".format(len(y.columns)))
                y = y[y.columns[0]]
            elif y is None:
                raise CatBoostError("y should be specified.")
            y = np.array(y)
            predicted_classes = self._predict(X, prediction_type='Class', 
             ntree_start=0, ntree_end=0, thread_count=-1, verbose=None, 
             parent_method_name='score').reshape(-1)
            if np.issubdtype(predicted_classes.dtype, np.number):
                if np.issubdtype(y.dtype, np.character):
                    raise CatBoostError('predicted classes have numeric type 
                     but specified y contains strings')
            elif np.issubdtype(y.dtype, np.number):
                raise CatBoostError('predicted classes have string type but 
                 specified y is numeric')
            elif np.issubdtype(y.dtype, np.bool_):
                raise CatBoostError('predicted classes have string type but 
                 specified y is boolean')
            return np.mean(np.array(predicted_classes) == np.array(y))
        
        def _check_is_classification_objective(self, loss_function):
            if isinstance(loss_function, str) and not self.
             _is_classification_objective(loss_function):
                raise CatBoostError(
                    "Invalid loss_function='{}': for classifier use "
                    "Logloss, CrossEntropy, MultiClass, MultiClassOneVsAll 
                     or custom objective object".
                    format(loss_function))

[ML_CatBoost_CatBoost]: https://yunyaniu.blog.csdn.net/article/details/112550036
[ML_CatboostC_titanic_catboost]: https://yunyaniu.blog.csdn.net/article/details/114907282
[ML_CatboostC_titanic_catboost 1]: https://yunyaniu.blog.csdn.net/article/details/114907520
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMTg1ODY4_size_16_color_FFFFFF_t_70]: /images/20221023/5ce2518aea3d40ee99347f33f88ec00a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMTg1ODY4_size_16_color_FFFFFF_t_70 1]: /images/20221023/7ba106b93ad542359a1738d30d9337bd.png