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基于Lending Club的資料分析實戰專案【小白記錄向】【一】

2021-04-30 15:46:02 後端開發

本實戰專案基于Lending Club的資料集【資料集地址:https://github.com/H-Freax/lendingclub_analyse】

本實戰專案基于Colab環境

文章目錄

  • 簡介
  • 環境準備
  • 載入資料
  • 資料基本資訊查看/分析
  • BaseLine
    • data preprocessing
    • Algorithm
    • Train
    • Test
  • 添加衍生變數
    • CatBoostEncoder
      • data preprocessing
      • Algorithm
      • Train
      • Test
    • 離散化
      • 基于聚類continuous_open_acc
        • data preprocessing
        • Algorithm
        • Train
        • Test
      • 改用指數性區間劃分continuous_loan_amnt
        • data preprocessing
        • Algorithm
        • Train
        • Test
    • 基于業務邏輯分析的衍生變數
      • data preprocessing
      • Algorithm
      • Train
      • Test

簡介

本資料分析實戰專案分為兩篇,第一篇主要介紹了基于LightGBM的Baseline方法,以及三種添加衍生變數的方法,找到了四組可以提升效果的衍生變數,第二篇主要介紹了基于機器學習方法及深度學習網路方法的資料分析,同時對機器學習方法的集成以及將深度學習網路與機器學習方法的融合進行了實踐,

環境準備

本專案采用lightgbm作為baseline
首先引入相關包

import lightgbm as lgb
import numpy as np
import pandas as pd
from sklearn.model_selection import KFold
from sklearn.metrics import accuracy_score

載入資料

seed = 42 # for the same data division

kf = KFold(n_splits=5, random_state=seed,shuffle=True)
df_train = pd.read_csv('train_final.csv')
df_test = pd.read_csv('test_final.csv')

資料基本資訊查看/分析

查看df_train的基本資訊

df_train.describe()

為了進行資料分析的時候先跳過one-hot編碼的部分,先采用以下函式列出所有列名

df_train.columns.values

將one-hot編碼對應的變數排除以后進行可視化,查看規律

import matplotlib.pyplot as plt
onehotlabels=['discrete_addr_state_1_one_hot',
       'discrete_addr_state_2_one_hot', 'discrete_addr_state_3_one_hot',
       'discrete_addr_state_4_one_hot', 'discrete_addr_state_5_one_hot',
       'discrete_addr_state_6_one_hot', 'discrete_addr_state_7_one_hot',
       'discrete_addr_state_8_one_hot', 'discrete_addr_state_9_one_hot',
       'discrete_addr_state_10_one_hot', 'discrete_addr_state_11_one_hot',
       'discrete_addr_state_12_one_hot', 'discrete_addr_state_13_one_hot',
       'discrete_addr_state_14_one_hot', 'discrete_addr_state_15_one_hot',
       'discrete_addr_state_16_one_hot', 'discrete_addr_state_17_one_hot',
       'discrete_addr_state_18_one_hot', 'discrete_addr_state_19_one_hot',
       'discrete_addr_state_20_one_hot', 'discrete_addr_state_21_one_hot',
       'discrete_addr_state_22_one_hot', 'discrete_addr_state_23_one_hot',
       'discrete_addr_state_24_one_hot', 'discrete_addr_state_25_one_hot',
       'discrete_addr_state_26_one_hot', 'discrete_addr_state_27_one_hot',
       'discrete_addr_state_28_one_hot', 'discrete_addr_state_29_one_hot',
       'discrete_addr_state_30_one_hot', 'discrete_addr_state_31_one_hot',
       'discrete_addr_state_32_one_hot', 'discrete_addr_state_33_one_hot',
       'discrete_addr_state_34_one_hot', 'discrete_addr_state_35_one_hot',
       'discrete_addr_state_36_one_hot', 'discrete_addr_state_37_one_hot',
       'discrete_addr_state_38_one_hot', 'discrete_addr_state_39_one_hot',
       'discrete_addr_state_40_one_hot', 'discrete_addr_state_41_one_hot',
       'discrete_addr_state_42_one_hot', 'discrete_addr_state_43_one_hot',
       'discrete_addr_state_44_one_hot', 'discrete_addr_state_45_one_hot',
       'discrete_addr_state_46_one_hot', 'discrete_addr_state_47_one_hot',
       'discrete_addr_state_48_one_hot', 'discrete_addr_state_49_one_hot',
       'discrete_application_type_1_one_hot',
       'discrete_application_type_2_one_hot',
       'discrete_emp_length_1_one_hot', 'discrete_emp_length_2_one_hot',
       'discrete_emp_length_3_one_hot', 'discrete_emp_length_4_one_hot',
       'discrete_emp_length_5_one_hot', 'discrete_emp_length_6_one_hot',
       'discrete_emp_length_7_one_hot', 'discrete_emp_length_8_one_hot',
       'discrete_emp_length_9_one_hot', 'discrete_emp_length_10_one_hot',
       'discrete_emp_length_11_one_hot', 'discrete_emp_length_12_one_hot',
       'discrete_grade_1_one_hot', 'discrete_grade_2_one_hot',
       'discrete_grade_3_one_hot', 'discrete_grade_4_one_hot',
       'discrete_grade_5_one_hot', 'discrete_grade_6_one_hot',
       'discrete_grade_7_one_hot', 'discrete_home_ownership_1_one_hot',
       'discrete_home_ownership_2_one_hot',
       'discrete_home_ownership_3_one_hot',
       'discrete_home_ownership_4_one_hot',
       'discrete_policy_code_1_one_hot', 'discrete_purpose_1_one_hot',
       'discrete_purpose_2_one_hot', 'discrete_purpose_3_one_hot',
       'discrete_purpose_4_one_hot', 'discrete_purpose_5_one_hot',
       'discrete_purpose_6_one_hot', 'discrete_purpose_7_one_hot',
       'discrete_purpose_8_one_hot', 'discrete_purpose_9_one_hot',
       'discrete_purpose_10_one_hot', 'discrete_purpose_11_one_hot',
       'discrete_purpose_12_one_hot', 'discrete_pymnt_plan_1_one_hot',
       'discrete_sub_grade_1_one_hot', 'discrete_sub_grade_2_one_hot',
       'discrete_sub_grade_3_one_hot', 'discrete_sub_grade_4_one_hot',
       'discrete_sub_grade_5_one_hot', 'discrete_sub_grade_6_one_hot',
       'discrete_sub_grade_7_one_hot', 'discrete_sub_grade_8_one_hot',
       'discrete_sub_grade_9_one_hot', 'discrete_sub_grade_10_one_hot',
       'discrete_sub_grade_11_one_hot', 'discrete_sub_grade_12_one_hot',
       'discrete_sub_grade_13_one_hot', 'discrete_sub_grade_14_one_hot',
       'discrete_sub_grade_15_one_hot', 'discrete_sub_grade_16_one_hot',
       'discrete_sub_grade_17_one_hot', 'discrete_sub_grade_18_one_hot',
       'discrete_sub_grade_19_one_hot', 'discrete_sub_grade_20_one_hot',
       'discrete_sub_grade_21_one_hot', 'discrete_sub_grade_22_one_hot',
       'discrete_sub_grade_23_one_hot', 'discrete_sub_grade_24_one_hot',
       'discrete_sub_grade_25_one_hot', 'discrete_sub_grade_26_one_hot',
       'discrete_sub_grade_27_one_hot', 'discrete_sub_grade_28_one_hot',
       'discrete_sub_grade_29_one_hot', 'discrete_sub_grade_30_one_hot',
       'discrete_sub_grade_31_one_hot', 'discrete_sub_grade_32_one_hot',
       'discrete_sub_grade_33_one_hot', 'discrete_sub_grade_34_one_hot',
       'discrete_sub_grade_35_one_hot', 'discrete_term_1_one_hot',
       'discrete_term_2_one_hot','loan_status']
showdf_train=df_train.drop(columns=onehotlabels)
showdf_train.hist(bins=50,figsize=(20,15))
plt.show()

在這里插入圖片描述
由于continuous_fico_range與continuous_last_fico_range存在上下界且有高相關性,故刪去high的部分進行進一步可視化分析

from pandas.plotting import scatter_matrix
scatter_matrix(showdf_train.drop(columns=['continuous_fico_range_high','continuous_last_fico_range_high']),figsize=(40,35))

在這里插入圖片描述

BaseLine

data preprocessing

X_train = df_train.drop(columns=['loan_status']).values
Y_train = df_train['loan_status'].values.astype(int)
X_test = df_test.drop(columns=['loan_status']).values
Y_test = df_test['loan_status'].values.astype(int)

# split data for five fold

five_fold_data = []

for train_index, eval_index in kf.split(X_train):
    x_train, x_eval = X_train[train_index], X_train[eval_index]
    y_train, y_eval = Y_train[train_index], Y_train[eval_index]
    
    five_fold_data.append([(x_train, y_train), (x_eval, y_eval)])
X_train.shape, Y_train.shape

Algorithm

def get_model(param):
    model_list = []
    for idx, [(x_train, y_train), (x_eval, y_eval)] in enumerate(five_fold_data):
        print('{}-th model is training:'.format(idx))
        train_data = lgb.Dataset(x_train, label=y_train)
        validation_data = lgb.Dataset(x_eval, label=y_eval)
        bst = lgb.train(param, train_data, valid_sets=[validation_data])
        model_list.append(bst)
    return model_list

Train

param_base = {'num_leaves': 31, 'objective': 'binary', 'metric': 'binary', 'num_round':1000}

param_fine_tuning = {'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 1000, 
                     'learning_rate': 3e-3, 'feature_fraction': 0.6, 'bagging_fraction': 0.8}
# base param train
param_base_model = get_model(param_base)

# param fine tuning
param_fine_tuning_model = get_model(param_fine_tuning)

Test

def test_model(model_list):
    data = X_test
    five_fold_pred = np.zeros((5, len(X_test)))
    for i, bst in enumerate(model_list):
        ypred = bst.predict(data, num_iteration=bst.best_iteration)
        five_fold_pred[i] = ypred
    ypred_mean = (five_fold_pred.mean(axis=-2)>0.5).astype(int)
    return accuracy_score(ypred_mean, Y_test)
base_score = test_model(param_base_model)
fine_tuning_score = test_model(param_fine_tuning_model)

print('base: {}, fine tuning: {}'.format(base_score, fine_tuning_score))

添加衍生變數

CatBoostEncoder

匯入相關環境

pip install category_encoders
import category_encoders as ce #CatBoostEncoder的相關包
#Create the encoder
target_enc = ce.CatBoostEncoder(cols='continuous_open_acc')
target_enc.fit(df_train['continuous_open_acc'], df_train['loan_status'])
#Transform the features, rename columns with _cb suffix, and join to dataframe
train_CBE = df_train.join(target_enc.transform(df_train['continuous_open_acc']).add_suffix('_cb'))
test_CBE = df_test.join(target_enc.transform(df_test['continuous_open_acc']).add_suffix('_cb'))

data preprocessing

X_train = train_CBE.drop(columns=['loan_status']).values
Y_train = train_CBE['loan_status'].values.astype(int)
X_test = test_CBE.drop(columns=['loan_status']).values
Y_test = test_CBE['loan_status'].values.astype(int)

# split data for five fold

five_fold_data = []

for train_index, eval_index in kf.split(X_train):
    x_train, x_eval = X_train[train_index], X_train[eval_index]
    y_train, y_eval = Y_train[train_index], Y_train[eval_index]
    
    five_fold_data.append([(x_train, y_train), (x_eval, y_eval)])

Algorithm

def get_model(param):
    model_list = []
    for idx, [(x_train, y_train), (x_eval, y_eval)] in enumerate(five_fold_data):
        print('{}-th model is training:'.format(idx))
        train_data = lgb.Dataset(x_train, label=y_train)
        validation_data = lgb.Dataset(x_eval, label=y_eval)
        bst = lgb.train(param, train_data, valid_sets=[validation_data])
        model_list.append(bst)
    return model_list

Train

param_base = {'num_leaves': 31, 'objective': 'binary', 'metric': 'binary', 'num_round':1000}

param_fine_tuning = {'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 1000, 
                     'learning_rate': 3e-3, 'feature_fraction': 0.6, 'bagging_fraction': 0.8}

param_fine_tuningfinal={'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 1200, 
                     'learning_rate': 3e-3, 'feature_fraction': 0.6, 'bagging_fraction': 0.8}
# base param train
param_base_model = get_model(param_base)

# param fine tuning
param_fine_tuning_model = get_model(param_fine_tuning)


param_fine_tuningfinal_model = get_model(param_fine_tuningfinal)

Test

def test_model(model_list):
    data = X_test
    five_fold_pred = np.zeros((5, len(X_test)))
    for i, bst in enumerate(model_list):
        ypred = bst.predict(data, num_iteration=bst.best_iteration)
        five_fold_pred[i] = ypred
    ypred_mean = (five_fold_pred.mean(axis=-2)>0.5).astype(int)
    return accuracy_score(ypred_mean, Y_test)
base_score = test_model(param_base_model)
fine_tuning_score = test_model(param_fine_tuning_model)
fine_tuningfinal_score=test_model(param_fine_tuningfinal_model)

print('base: {}, fine tuning: {} , fine tuning final: {}'.format(base_score, fine_tuning_score, fine_tuningfinal_score))

base: 0.91568, fine tuning: 0.91774 , fine tuning final: 0.91796

離散化

基于聚類continuous_open_acc

df_train.groupby('continuous_open_acc')['continuous_open_acc'].unique()
!pip install KMeans
from sklearn.cluster import KMeans

ddtrain=df_train['continuous_open_acc']
ddtest=df_test['continuous_open_acc']
data_reshape1=ddtrain.values.reshape((ddtrain.shape[0],1))
model_kmeans=KMeans(n_clusters=5,random_state=0)
kmeans_result=model_kmeans.fit_predict(data_reshape1)
traina=kmeans_result

data_reshape2=ddtest.values.reshape((ddtest.shape[0],1))
model_kmeans=KMeans(n_clusters=5,random_state=0)
kmeans_result=model_kmeans.fit_predict(data_reshape2)
testa=kmeans_result

train_KM = df_train.copy()
test_KM = df_test.copy()

train_KM['continuous_open_acc_km']=traina
test_KM['continuous_open_acc_km']=testa

data preprocessing

X_train = train_KM.drop(columns=['loan_status']).values
Y_train = train_KM['loan_status'].values.astype(int)
X_test = test_KM.drop(columns=['loan_status']).values
Y_test = test_KM['loan_status'].values.astype(int)

# split data for five fold

five_fold_data = []

for train_index, eval_index in kf.split(X_train):
    x_train, x_eval = X_train[train_index], X_train[eval_index]
    y_train, y_eval = Y_train[train_index], Y_train[eval_index]
    
    five_fold_data.append([(x_train, y_train), (x_eval, y_eval)])

Algorithm

def get_model(param):
    model_list = []
    for idx, [(x_train, y_train), (x_eval, y_eval)] in enumerate(five_fold_data):
        print('{}-th model is training:'.format(idx))
        train_data = lgb.Dataset(x_train, label=y_train)
        validation_data = lgb.Dataset(x_eval, label=y_eval)
        bst = lgb.train(param, train_data, valid_sets=[validation_data])
        model_list.append(bst)
    return model_list

Train

param_base = {'num_leaves': 31, 'objective': 'binary', 'metric': 'binary', 'num_round':1000}

param_fine_tuning = {'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 1000, 
                     'learning_rate': 3e-3, 'feature_fraction': 0.6, 'bagging_fraction': 0.8}



                     
param_fine_tuningfinal={'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 800,
                     'learning_rate': 6e-3, 'feature_fraction': 0.8, 'bagging_fraction': 0.6,'boosting':'goss','tree_learning':'feature','max_depth':20,'min_sum_hessian_in_leaf':100}

# # base param train
param_base_model = get_model(param_base)

# # param fine tuning
param_fine_tuning_model = get_model(param_fine_tuning)

param_fine_tuningfinal_model = get_model(param_fine_tuningfinal)

Test

def test_model(model_list):
    data = X_test
    five_fold_pred = np.zeros((5, len(X_test)))
    for i, bst in enumerate(model_list):
        ypred = bst.predict(data, num_iteration=bst.best_iteration)
        five_fold_pred[i] = ypred
    ypred_mean = (five_fold_pred.mean(axis=-2)>0.5).astype(int)
    return accuracy_score(ypred_mean, Y_test)
base_score = test_model(param_base_model)
fine_tuning_score = test_model(param_fine_tuning_model)
fine_tuningfinal_score=test_model(param_fine_tuningfinal_model)

print('base: {}, fine tuning: {} , fine tuning final: {}'.format(base_score, fine_tuning_score, fine_tuningfinal_score))

base: 0.91598, fine tuning: 0.91776 , fine tuning final: 0.91874

改用指數性區間劃分continuous_loan_amnt

train_ZQ = df_train.copy()
test_ZQ = df_test.copy()

trainbins=np.floor(np.log10(train_ZQ['continuous_loan_amnt']))   #取對數之后再向下取整
testbins=np.floor(np.log10(test_ZQ['continuous_loan_amnt']))

train_ZQ['continuous_loan_amnt_km']=trainbins
test_ZQ['continuous_loan_amnt_km']=testbins

data preprocessing

X_train = train_ZQ.drop(columns=['loan_status']).values
Y_train = train_ZQ['loan_status'].values.astype(int)
X_test = test_ZQ.drop(columns=['loan_status']).values
Y_test = test_ZQ['loan_status'].values.astype(int)

# split data for five fold

five_fold_data = []

for train_index, eval_index in kf.split(X_train):
    x_train, x_eval = X_train[train_index], X_train[eval_index]
    y_train, y_eval = Y_train[train_index], Y_train[eval_index]
    
    five_fold_data.append([(x_train, y_train), (x_eval, y_eval)])

Algorithm

def get_model(param):
    model_list = []
    for idx, [(x_train, y_train), (x_eval, y_eval)] in enumerate(five_fold_data):
        print('{}-th model is training:'.format(idx))
        train_data = lgb.Dataset(x_train, label=y_train)
        validation_data = lgb.Dataset(x_eval, label=y_eval)
        bst = lgb.train(param, train_data, valid_sets=[validation_data])
        model_list.append(bst)
    return model_list

Train

param_base = {'num_leaves': 31, 'objective': 'binary', 'metric': 'binary', 'num_round':1000}

param_fine_tuning = {'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 1000, 
                     'learning_rate': 3e-3, 'feature_fraction': 0.6, 'bagging_fraction': 0.8}


param_fine_tuningfinal={'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 900, 
                     'learning_rate': 7e-3, 'feature_fraction': 0.8, 'bagging_fraction': 0.6,'max_depth':20,'min_sum_hessian_in_leaf':100}
# base param train
param_base_model = get_model(param_base)

# param fine tuning
param_fine_tuning_model = get_model(param_fine_tuning)

param_fine_tuningfinal_model = get_model(param_fine_tuningfinal)

Test

def test_model(model_list):
    data = X_test
    five_fold_pred = np.zeros((5, len(X_test)))
    for i, bst in enumerate(model_list):
        ypred = bst.predict(data, num_iteration=bst.best_iteration)
        five_fold_pred[i] = ypred
    ypred_mean = (five_fold_pred.mean(axis=-2)>0.5).astype(int)
    return accuracy_score(ypred_mean, Y_test)
base_score = test_model(param_base_model)
fine_tuning_score = test_model(param_fine_tuning_model)
fine_tuningfinal_score=test_model(param_fine_tuningfinal_model)

print('base: {}, fine tuning: {} , fine tuning final: {}'.format(base_score, fine_tuning_score, fine_tuningfinal_score))

base: 0.91586, fine tuning: 0.91764 , fine tuning final: 0.91842

基于業務邏輯分析的衍生變數

train_YW = df_train.copy()
test_YW = df_test.copy()



train_YW['installment_feat']=train_YW['continuous_installment'] / ((train_YW['continuous_annual_inc']+1) / 12)
test_YW['installment_feat']=test_YW['continuous_installment'] / ((test_YW['continuous_annual_inc']+1) / 12)


data preprocessing

X_train = train_YW.drop(columns=['loan_status']).values
Y_train = train_YW['loan_status'].values.astype(int)
X_test = test_YW.drop(columns=['loan_status']).values
Y_test = test_YW['loan_status'].values.astype(int)

# split data for five fold

five_fold_data = []

for train_index, eval_index in kf.split(X_train):
    x_train, x_eval = X_train[train_index], X_train[eval_index]
    y_train, y_eval = Y_train[train_index], Y_train[eval_index]
    
    five_fold_data.append([(x_train, y_train), (x_eval, y_eval)])

Algorithm

def get_model(param):
    model_list = []
    for idx, [(x_train, y_train), (x_eval, y_eval)] in enumerate(five_fold_data):
        print('{}-th model is training:'.format(idx))
        train_data = lgb.Dataset(x_train, label=y_train)
        validation_data = lgb.Dataset(x_eval, label=y_eval)
        bst = lgb.train(param, train_data, valid_sets=[validation_data])
        model_list.append(bst)
    return model_list

Train

param_base = {'num_leaves': 31, 'objective': 'binary', 'metric': 'binary', 'num_round':1000}

param_fine_tuning = {'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 1000, 
                     'learning_rate': 3e-3, 'feature_fraction': 0.6, 'bagging_fraction': 0.8}

param_fine_tuningfinal={'num_thread': 8,'num_leaves': 128, 'metric': 'binary', 'objective': 'binary', 'num_round': 900, 
                     'learning_rate': 7e-3, 'feature_fraction': 0.8, 'bagging_fraction': 0.6,'max_depth':20,'min_sum_hessian_in_leaf':100}
# base param train
param_base_model = get_model(param_base)

# param fine tuning
param_fine_tuning_model = get_model(param_fine_tuning)

param_fine_tuningfinal_model = get_model(param_fine_tuningfinal)

Test

def test_model(model_list):
    data = X_test
    five_fold_pred = np.zeros((5, len(X_test)))
    for i, bst in enumerate(model_list):
        ypred = bst.predict(data, num_iteration=bst.best_iteration)
        five_fold_pred[i] = ypred
    ypred_mean = (five_fold_pred.mean(axis=-2)>0.5).astype(int)
    return accuracy_score(ypred_mean, Y_test)
base_score = test_model(param_base_model)
fine_tuning_score = test_model(param_fine_tuning_model)
fine_tuningfinal_score=test_model(param_fine_tuningfinal_model)

print('base: {}, fine tuning: {} , fine tuning final: {}'.format(base_score, fine_tuning_score, fine_tuningfinal_score))

base: 0.9162, fine tuning: 0.91758 , fine tuning final: 0.91844

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