정규화(Rescaling)

def mean_centering(X, Y): 
    X = X - X.mean()
    Y = Y - Y.mean()
    return X, Y 

def z_transform(X, Y): 
    X = (X - X.mean()) / X.std()
    Y = (Y - Y.mean()) / Y.std()
    return X, Y
    
# 이상치에 덜 민감한 scaling 방법 찾기 

from sklearn.preprocessing import StandardScaler, MinMaxScaler, RobustScaler

def standard_scaling(X, Y): 
    # StandardScaler
    standard_scaler = StandardScaler()
    X = standard_scaler.fit_transform(X)
    Y = standard_scaler.fit_transform(Y)
    return X, Y

def minmax_scaling(X, Y): 
    # MinMaxScaler
    minmax_scaler = MinMaxScaler()
    X = minmax_scaler.fit_transform(X)
    Y = minmax_scaler.fit_transform(Y)
    return X, Y

def robust_scaling(X, Y): 
    # RobustScaler
    robust_scaler = RobustScaler()
    X = robust_scaler.fit_transform(X)
    Y = robust_scaler.fit_transform(Y)
    return X, Y