In [8]:
import numpy as np
import pandas as pd
import gc
import time
from contextlib import contextmanager
from lightgbm import LGBMClassifier
from sklearn.metrics import roc_auc_score, roc_curve
from sklearn.model_selection import KFold, StratifiedKFold
import matplotlib.pyplot as plt
import seaborn as sns
import warnings
warnings.simplefilter(action='ignore', category=FutureWarning)

@contextmanager
def timer(title):
    t0 = time.time()
    yield
    print("{} - done in {:.0f}s".format(title, time.time() - t0))

# One-hot encoding for categorical columns with get_dummies
def one_hot_encoder(df, nan_as_category = True):
    original_columns = list(df.columns)
    categorical_columns = [col for col in df.columns if df[col].dtype == 'object']
    df = pd.get_dummies(df, columns= categorical_columns, dummy_na= nan_as_category)
    new_columns = [c for c in df.columns if c not in original_columns]
    return df, new_columns

# Preprocess application_train.csv and application_test.csv
def application_train_test(num_rows = None, nan_as_category = False):
    # Read data and merge
    df = pd.read_csv(r'.\input\application_train.csv', nrows= num_rows)
    test_df = pd.read_csv(r'.\input\application_test.csv', nrows= num_rows)
    print("Train samples: {}, test samples: {}".format(len(df), len(test_df)))
    df = df.append(test_df).reset_index()
    # Optional: Remove 4 applications with XNA CODE_GENDER (train set)
    df = df[df['CODE_GENDER'] != 'XNA']
    
    docs = [_f for _f in df.columns if 'FLAG_DOC' in _f]
    live = [_f for _f in df.columns if ('FLAG_' in _f) & ('FLAG_DOC' not in _f) & ('_FLAG_' not in _f)]
    
    # NaN values for DAYS_EMPLOYED: 365.243 -> nan
    df['DAYS_EMPLOYED'].replace(365243, np.nan, inplace= True)

    inc_by_org = df[['AMT_INCOME_TOTAL', 'ORGANIZATION_TYPE']].groupby('ORGANIZATION_TYPE').median()['AMT_INCOME_TOTAL']

    df['NEW_CREDIT_TO_ANNUITY_RATIO'] = df['AMT_CREDIT'] / df['AMT_ANNUITY']
    df['NEW_CREDIT_TO_GOODS_RATIO'] = df['AMT_CREDIT'] / df['AMT_GOODS_PRICE']
    df['NEW_DOC_IND_KURT'] = df[docs].kurtosis(axis=1)
    df['NEW_LIVE_IND_SUM'] = df[live].sum(axis=1)
    df['NEW_INC_PER_CHLD'] = df['AMT_INCOME_TOTAL'] / (1 + df['CNT_CHILDREN'])
    df['NEW_INC_BY_ORG'] = df['ORGANIZATION_TYPE'].map(inc_by_org)
    df['NEW_EMPLOY_TO_BIRTH_RATIO'] = df['DAYS_EMPLOYED'] / df['DAYS_BIRTH']
    df['NEW_ANNUITY_TO_INCOME_RATIO'] = df['AMT_ANNUITY'] / (1 + df['AMT_INCOME_TOTAL'])
    df['NEW_SOURCES_PROD'] = df['EXT_SOURCE_1'] * df['EXT_SOURCE_2'] * df['EXT_SOURCE_3']
    df['NEW_EXT_SOURCES_MEAN'] = df[['EXT_SOURCE_1', 'EXT_SOURCE_2', 'EXT_SOURCE_3']].mean(axis=1)
    df['NEW_SCORES_STD'] = df[['EXT_SOURCE_1', 'EXT_SOURCE_2', 'EXT_SOURCE_3']].std(axis=1)
    df['NEW_SCORES_STD'] = df['NEW_SCORES_STD'].fillna(df['NEW_SCORES_STD'].mean())
    df['NEW_CAR_TO_BIRTH_RATIO'] = df['OWN_CAR_AGE'] / df['DAYS_BIRTH']
    df['NEW_CAR_TO_EMPLOY_RATIO'] = df['OWN_CAR_AGE'] / df['DAYS_EMPLOYED']
    df['NEW_PHONE_TO_BIRTH_RATIO'] = df['DAYS_LAST_PHONE_CHANGE'] / df['DAYS_BIRTH']
    df['NEW_PHONE_TO_BIRTH_RATIO_EMPLOYER'] = df['DAYS_LAST_PHONE_CHANGE'] / df['DAYS_EMPLOYED']
    df['NEW_CREDIT_TO_INCOME_RATIO'] = df['AMT_CREDIT'] / df['AMT_INCOME_TOTAL']
    
    # Categorical features with Binary encode (0 or 1; two categories)
    for bin_feature in ['CODE_GENDER', 'FLAG_OWN_CAR', 'FLAG_OWN_REALTY']:
        df[bin_feature], uniques = pd.factorize(df[bin_feature])
    # Categorical features with One-Hot encode
    df, cat_cols = one_hot_encoder(df, nan_as_category)
    dropcolum=['FLAG_DOCUMENT_2','FLAG_DOCUMENT_4',
    'FLAG_DOCUMENT_5','FLAG_DOCUMENT_6','FLAG_DOCUMENT_7',
    'FLAG_DOCUMENT_8','FLAG_DOCUMENT_9','FLAG_DOCUMENT_10', 
    'FLAG_DOCUMENT_11','FLAG_DOCUMENT_12','FLAG_DOCUMENT_13',
    'FLAG_DOCUMENT_14','FLAG_DOCUMENT_15','FLAG_DOCUMENT_16',
    'FLAG_DOCUMENT_17','FLAG_DOCUMENT_18','FLAG_DOCUMENT_19',
    'FLAG_DOCUMENT_20','FLAG_DOCUMENT_21']
    df= df.drop(dropcolum,axis=1)
    del test_df
    gc.collect()
    return df

# Preprocess bureau.csv and bureau_balance.csv
def bureau_and_balance(num_rows = None, nan_as_category = True):
    bureau = pd.read_csv('./input/bureau.csv', nrows = num_rows)
    bb = pd.read_csv('./input/bureau_balance.csv', nrows = num_rows)
    bb, bb_cat = one_hot_encoder(bb, nan_as_category)
    bureau, bureau_cat = one_hot_encoder(bureau, nan_as_category)
    
    # Bureau balance: Perform aggregations and merge with bureau.csv
    bb_aggregations = {'MONTHS_BALANCE': ['min', 'max', 'size']}
    for col in bb_cat:
        bb_aggregations[col] = ['mean']
    bb_agg = bb.groupby('SK_ID_BUREAU').agg(bb_aggregations)
    bb_agg.columns = pd.Index([e[0] + "_" + e[1].upper() for e in bb_agg.columns.tolist()])
    bureau = pd.merge(bureau,bb_agg, how='left',  left_index=True, right_index=True)
    #bureau = bureau.join(bb_agg, how='left', on='SK_ID_BUREAU')
    bureau.drop(['SK_ID_BUREAU'], axis=1, inplace= True)
    del bb, bb_agg
    gc.collect()
    
    # Bureau and bureau_balance numeric features
    num_aggregations = {
        'DAYS_CREDIT': [ 'mean', 'var'],
        'DAYS_CREDIT_ENDDATE': [ 'mean'],
        'DAYS_CREDIT_UPDATE': ['mean'],
        'CREDIT_DAY_OVERDUE': ['mean'],
        'AMT_CREDIT_MAX_OVERDUE': ['mean'],
        'AMT_CREDIT_SUM': [ 'mean', 'sum'],
        'AMT_CREDIT_SUM_DEBT': [ 'mean', 'sum'],
        'AMT_CREDIT_SUM_OVERDUE': ['mean'],
        'AMT_CREDIT_SUM_LIMIT': ['mean', 'sum'],
        'AMT_ANNUITY': ['max', 'mean'],
        'CNT_CREDIT_PROLONG': ['sum'],
        'MONTHS_BALANCE_MIN': ['min'],
        'MONTHS_BALANCE_MAX': ['max'],
        'MONTHS_BALANCE_SIZE': ['mean', 'sum']
    }
    # Bureau and bureau_balance categorical features
    cat_aggregations = {}
    for cat in bureau_cat: cat_aggregations[cat] = ['mean']
    for cat in bb_cat: cat_aggregations[cat + "_MEAN"] = ['mean']
    
    bureau_agg = bureau.groupby('SK_ID_CURR').agg({**num_aggregations, **cat_aggregations})
    bureau_agg.columns = pd.Index(['BURO_' + e[0] + "_" + e[1].upper() for e in bureau_agg.columns.tolist()])
    # Bureau: Active credits - using only numerical aggregations
    active = bureau[bureau['CREDIT_ACTIVE_Active'] == 1]
    active_agg = active.groupby('SK_ID_CURR').agg(num_aggregations)
    active_agg.columns = pd.Index(['ACTIVE_' + e[0] + "_" + e[1].upper() for e in active_agg.columns.tolist()])
    bureau_agg = pd.merge(bureau_agg,active_agg, how='left',  left_index=True, right_index=True)
    del active, active_agg
    gc.collect()
    # Bureau: Closed credits - using only numerical aggregations
    closed = bureau[bureau['CREDIT_ACTIVE_Closed'] == 1]
    closed_agg = closed.groupby('SK_ID_CURR').agg(num_aggregations)
    closed_agg.columns = pd.Index(['CLOSED_' + e[0] + "_" + e[1].upper() for e in closed_agg.columns.tolist()])
    bureau_agg = pd.merge(bureau_agg,closed_agg, how='left',  left_index=True, right_index=True)
    #bureau_agg = bureau_agg.join(closed_agg, how='left', on='SK_ID_CURR')
    del closed, closed_agg, bureau
    gc.collect()
    return bureau_agg

# Preprocess previous_applications.csv
def previous_applications(num_rows = None, nan_as_category = True):
    prev = pd.read_csv('./input/previous_application.csv', nrows = num_rows)
    prev, cat_cols = one_hot_encoder(prev, nan_as_category= True)
    # Days 365.243 values -> nan
    prev['DAYS_FIRST_DRAWING'].replace(365243, np.nan, inplace= True)
    prev['DAYS_FIRST_DUE'].replace(365243, np.nan, inplace= True)
    prev['DAYS_LAST_DUE_1ST_VERSION'].replace(365243, np.nan, inplace= True)
    prev['DAYS_LAST_DUE'].replace(365243, np.nan, inplace= True)
    prev['DAYS_TERMINATION'].replace(365243, np.nan, inplace= True)
    # Add feature: value ask / value received percentage
    prev['APP_CREDIT_PERC'] = prev['AMT_APPLICATION'] / prev['AMT_CREDIT']
    # Previous applications numeric features
    num_aggregations = {
        'AMT_ANNUITY': [ 'max', 'mean'],
        'AMT_APPLICATION': [ 'max','mean'],
        'AMT_CREDIT': [ 'max', 'mean'],
        'APP_CREDIT_PERC': [ 'max', 'mean'],
        'AMT_DOWN_PAYMENT': [ 'max', 'mean'],
        'AMT_GOODS_PRICE': [ 'max', 'mean'],
        'HOUR_APPR_PROCESS_START': [ 'max', 'mean'],
        'RATE_DOWN_PAYMENT': [ 'max', 'mean'],
        'DAYS_DECISION': [ 'max', 'mean'],
        'CNT_PAYMENT': ['mean', 'sum'],
    }
    # Previous applications categorical features
    cat_aggregations = {}
    for cat in cat_cols:
        cat_aggregations[cat] = ['mean']
    
    prev_agg = prev.groupby('SK_ID_CURR').agg({**num_aggregations, **cat_aggregations})
    prev_agg.columns = pd.Index(['PREV_' + e[0] + "_" + e[1].upper() for e in prev_agg.columns.tolist()])
    # Previous Applications: Approved Applications - only numerical features
    approved = prev[prev['NAME_CONTRACT_STATUS_Approved'] == 1]
    approved_agg = approved.groupby('SK_ID_CURR').agg(num_aggregations)
    approved_agg.columns = pd.Index(['APPROVED_' + e[0] + "_" + e[1].upper() for e in approved_agg.columns.tolist()])
    prev_agg = pd.merge(prev_agg,approved_agg, how='left',  left_index=True, right_index=True)
    #prev_agg = prev_agg.join(approved_agg, how='left', on='SK_ID_CURR')
    # Previous Applications: Refused Applications - only numerical features
    refused = prev[prev['NAME_CONTRACT_STATUS_Refused'] == 1]
    refused_agg = refused.groupby('SK_ID_CURR').agg(num_aggregations)
    refused_agg.columns = pd.Index(['REFUSED_' + e[0] + "_" + e[1].upper() for e in refused_agg.columns.tolist()])
    prev_agg = pd.merge(prev_agg,refused_agg, how='left',  left_index=True, right_index=True)
    #prev_agg = prev_agg.join(refused_agg, how='left', on='SK_ID_CURR')
    del refused, refused_agg, approved, approved_agg, prev
    gc.collect()
    return prev_agg

# Preprocess POS_CASH_balance.csv
def pos_cash(num_rows = None, nan_as_category = True):
    pos = pd.read_csv('./input/POS_CASH_balance.csv', nrows = num_rows)
    pos, cat_cols = one_hot_encoder(pos, nan_as_category= True)
    # Features
    aggregations = {
        'MONTHS_BALANCE': ['max', 'mean', 'size'],
        'SK_DPD': ['max', 'mean'],
        'SK_DPD_DEF': ['max', 'mean']
    }
    for cat in cat_cols:
        aggregations[cat] = ['mean']
    
    pos_agg = pos.groupby('SK_ID_CURR').agg(aggregations)
    pos_agg.columns = pd.Index(['POS_' + e[0] + "_" + e[1].upper() for e in pos_agg.columns.tolist()])
    # Count pos cash accounts
    pos_agg['POS_COUNT'] = pos.groupby('SK_ID_CURR').size()
    del pos
    gc.collect()
    return pos_agg
    
# Preprocess installments_payments.csv
def installments_payments(num_rows = None, nan_as_category = True):
    ins = pd.read_csv('./input/installments_payments.csv', nrows = num_rows)
    ins, cat_cols = one_hot_encoder(ins, nan_as_category= True)
    # Percentage and difference paid in each installment (amount paid and installment value)
    ins['PAYMENT_PERC'] = ins['AMT_PAYMENT'] / ins['AMT_INSTALMENT']
    ins['PAYMENT_DIFF'] = ins['AMT_INSTALMENT'] - ins['AMT_PAYMENT']
    # Days past due and days before due (no negative values)
    ins['DPD'] = ins['DAYS_ENTRY_PAYMENT'] - ins['DAYS_INSTALMENT']
    ins['DBD'] = ins['DAYS_INSTALMENT'] - ins['DAYS_ENTRY_PAYMENT']
    ins['DPD'] = ins['DPD'].apply(lambda x: x if x > 0 else 0)
    ins['DBD'] = ins['DBD'].apply(lambda x: x if x > 0 else 0)
    # Features: Perform aggregations
    aggregations = {
        'NUM_INSTALMENT_VERSION': ['nunique'],
        'DPD': ['max', 'mean', 'sum','min','std' ],
        'DBD': ['max', 'mean', 'sum','min','std'],
        'PAYMENT_PERC': [ 'max','mean',  'var','min','std'],
        'PAYMENT_DIFF': [ 'max','mean', 'var','min','std'],
        'AMT_INSTALMENT': ['max', 'mean', 'sum','min','std'],
        'AMT_PAYMENT': ['min', 'max', 'mean', 'sum','std'],
        'DAYS_ENTRY_PAYMENT': ['max', 'mean', 'sum','std']
    }
    for cat in cat_cols:
        aggregations[cat] = ['mean']
    ins_agg = ins.groupby('SK_ID_CURR').agg(aggregations)
    ins_agg.columns = pd.Index(['INSTAL_' + e[0] + "_" + e[1].upper() for e in ins_agg.columns.tolist()])
    # Count installments accounts
    ins_agg['INSTAL_COUNT'] = ins.groupby('SK_ID_CURR').size()
    del ins
    gc.collect()
    return ins_agg

# Preprocess credit_card_balance.csv
def credit_card_balance(num_rows = None, nan_as_category = True):
    cc = pd.read_csv('./input/credit_card_balance.csv', nrows = num_rows)
    cc, cat_cols = one_hot_encoder(cc, nan_as_category= True)
    # General aggregations
    cc.drop(['SK_ID_PREV'], axis= 1, inplace = True)
    cc_agg = cc.groupby('SK_ID_CURR').agg([ 'max', 'mean', 'sum', 'var'])
    cc_agg.columns = pd.Index(['CC_' + e[0] + "_" + e[1].upper() for e in cc_agg.columns.tolist()])
    # Count credit card lines
    cc_agg['CC_COUNT'] = cc.groupby('SK_ID_CURR').size()
    del cc
    gc.collect()
    return cc_agg

# LightGBM GBDT with KFold or Stratified KFold
# Parameters from Tilii kernel: https://www.kaggle.com/tilii7/olivier-lightgbm-parameters-by-bayesian-opt/code
def kfold_lightgbm(df, num_folds, stratified = False, debug= False):
    # Divide in training/validation and test data
    train_df = df[df['TARGET'].notnull()]
    test_df = df[df['TARGET'].isnull()]
    print("Starting LightGBM. Train shape: {}, test shape: {}".format(train_df.shape, test_df.shape))
    del df
    gc.collect()
    # Cross validation model
    if stratified:
        folds = StratifiedKFold(n_splits= num_folds, shuffle=True, random_state=47)
    else:
        folds = KFold(n_splits= num_folds, shuffle=True, random_state=47)
    # Create arrays and dataframes to store results
    oof_preds = np.zeros(train_df.shape[0])
    sub_preds = np.zeros(test_df.shape[0])
    feature_importance_df = pd.DataFrame()
    feats = [f for f in train_df.columns if f not in ['TARGET','SK_ID_CURR','SK_ID_BUREAU','SK_ID_PREV','index']]
    
    for n_fold, (train_idx, valid_idx) in enumerate(folds.split(train_df[feats], train_df['TARGET'])):
        train_x, train_y = train_df[feats].iloc[train_idx], train_df['TARGET'].iloc[train_idx]
        valid_x, valid_y = train_df[feats].iloc[valid_idx], train_df['TARGET'].iloc[valid_idx]

        # LightGBM parameters found by Bayesian optimization
        clf = LGBMClassifier(
            boosting_type= 'gbdt', 
            colsample_bytree= 0.6014642048462456, 
            is_unbalance= False, learning_rate= 0.01222878983248616,
            min_child_samples= 500, num_leaves= 126, reg_alpha= 0.07936876591402212,
            reg_lambda= 0.28430717120489335, subsample_for_bin= 160000, subsample= 0.619083596793821,
            metric= 'auc', verbose= 1000, n_estimators= 1115
            )

        clf.fit(train_x, train_y, eval_set=[(train_x, train_y), (valid_x, valid_y)], 
            eval_metric= 'auc', verbose= 1000, early_stopping_rounds= 200)

        oof_preds[valid_idx] = clf.predict_proba(valid_x, num_iteration=clf.best_iteration_)[:, 1]
        sub_preds += clf.predict_proba(test_df[feats], num_iteration=clf.best_iteration_)[:, 1] / folds.n_splits

        fold_importance_df = pd.DataFrame()
        fold_importance_df["feature"] = feats
        fold_importance_df["importance"] = clf.feature_importances_
        fold_importance_df["fold"] = n_fold + 1
        feature_importance_df = pd.concat([feature_importance_df, fold_importance_df], axis=0)
        print('Fold %2d AUC : %.6f' % (n_fold + 1, roc_auc_score(valid_y, oof_preds[valid_idx])))
        del clf, train_x, train_y, valid_x, valid_y
        gc.collect()

    print('Full AUC score %.6f' % roc_auc_score(train_df['TARGET'], oof_preds))
    # Write submission file and plot feature importance
    if not debug:
        test_df['TARGET'] = sub_preds
        test_df[['SK_ID_CURR', 'TARGET']].to_csv(submission_file_name, index= False)
    display_importances(feature_importance_df)
    return feature_importance_df

# Display/plot feature importance
def display_importances(feature_importance_df_):
    cols = feature_importance_df_[["feature", "importance"]].groupby("feature").mean().sort_values(by="importance", ascending=False)[:40].index
    best_features = feature_importance_df_.loc[feature_importance_df_.feature.isin(cols)]
    plt.figure(figsize=(8, 10))
    sns.barplot(x="importance", y="feature", data=best_features.sort_values(by="importance", ascending=False))
    plt.title('LightGBM Features (avg over folds)')
    plt.tight_layout()
    plt.savefig('lgbm_importances01.png')

In [9]:
def main(debug = False):
    num_rows = 10000 if debug else None
    df = application_train_test(num_rows)
    with timer("Process bureau and bureau_balance"):
        bureau = bureau_and_balance(num_rows)
        print("Bureau df shape:", bureau.shape)
        df = df.join(bureau, how='left', on='SK_ID_CURR')
        del bureau
        gc.collect()
    with timer("Process previous_applications"):
        prev = previous_applications(num_rows)
        print("Previous applications df shape:", prev.shape)
        df = df.join(prev, how='left', on='SK_ID_CURR')
        del prev
        gc.collect()
    with timer("Process POS-CASH balance"):
        pos = pos_cash(num_rows)
        print("Pos-cash balance df shape:", pos.shape)
        df = df.join(pos, how='left', on='SK_ID_CURR')
        del pos
        gc.collect()
    with timer("Process installments payments"):
        ins = installments_payments(num_rows)
        print("Installments payments df shape:", ins.shape)
        df = df.join(ins, how='left', on='SK_ID_CURR')
        del ins
        gc.collect()
    with timer("Process credit card balance"):
        cc = credit_card_balance(num_rows)
        print("Credit card balance df shape:", cc.shape)
        df = df.join(cc, how='left', on='SK_ID_CURR')
        del cc
        gc.collect()
    with timer("Run LightGBM with kfold"):
        feat_importance = kfold_lightgbm(df, num_folds= 5, stratified= False, debug= debug)

if __name__ == "__main__":
    submission_file_name = "submission_kernel_paramOptim.csv"
    with timer("Full model run"):
        main()


Train samples: 307511, test samples: 48744
Bureau df shape: (305811, 95)
Process bureau and bureau_balance - done in 21s
Previous applications df shape: (338857, 219)
Process previous_applications - done in 23s
Pos-cash balance df shape: (337252, 18)
Process POS-CASH balance - done in 14s
Installments payments df shape: (339587, 36)
Process installments payments - done in 31s
Credit card balance df shape: (103558, 113)
Process credit card balance - done in 18s
Starting LightGBM. Train shape: (307507, 721), test shape: (48744, 721)
Training until validation scores don't improve for 200 rounds.
[1000]	training's auc: 0.9197	valid_1's auc: 0.792686
Did not meet early stopping. Best iteration is:
[1115]	training's auc: 0.931001	valid_1's auc: 0.793369
Fold  1 AUC : 0.793369
Training until validation scores don't improve for 200 rounds.
[1000]	training's auc: 0.919901	valid_1's auc: 0.791017
Did not meet early stopping. Best iteration is:
[1115]	training's auc: 0.930844	valid_1's auc: 0.791501
Fold  2 AUC : 0.791501
Training until validation scores don't improve for 200 rounds.
[1000]	training's auc: 0.919884	valid_1's auc: 0.790858
Did not meet early stopping. Best iteration is:
[1115]	training's auc: 0.930853	valid_1's auc: 0.791199
Fold  3 AUC : 0.791199
Training until validation scores don't improve for 200 rounds.
[1000]	training's auc: 0.919928	valid_1's auc: 0.791325
Did not meet early stopping. Best iteration is:
[1115]	training's auc: 0.93088	valid_1's auc: 0.791757
Fold  4 AUC : 0.791757
Training until validation scores don't improve for 200 rounds.
[1000]	training's auc: 0.920158	valid_1's auc: 0.78751
Did not meet early stopping. Best iteration is:
[1115]	training's auc: 0.931086	valid_1's auc: 0.788019
Fold  5 AUC : 0.788019
Full AUC score 0.791156
C:\Users\Insaf.Ashrapov\AppData\Local\Continuum\miniconda3\lib\site-packages\ipykernel_launcher.py:309: SettingWithCopyWarning: 
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead

See the caveats in the documentation: http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy
Run LightGBM with kfold - done in 2517s
Full model run - done in 2632s

In [ ]: