我正在使用sklearn在Jupyter中运行分类算法。
我想使用SMOTE,因为我的一个小组只有其他2个小组的35%。因此,我想对该组(第1组)进行超采样,但我不知道如何对其进行集成。 (编辑:我知道SMOTE脚本,但是我想知道它在下面的脚本中适合的位置)。
救命?
from sklearn.model_selection import train_test_split
X_train, X_test, y_train, y_test = train_test_split (X, y, test_size = 0.1)
from sklearn.preprocessing import StandardScaler
sc = StandardScaler()
X_train = sc.fit_transform(X_train)
X_test = sc.transform (X_test)
from sklearn.svm import SVC
clf = SVC(kernel = 'linear')
clf.fit (X_train, y_train.ravel())
y_pred = clf.predict(X_test)
from sklearn.metrics import confusion_matrix
cm = confusion_matrix (y_test, y_pred)
from sklearn.model_selection import cross_val_score
accuracies = cross_val_score (estimator = clf, X = X_train, y = y_train, cv = 10)
accuracies.mean()
accuracies.std()
from sklearn.model_selection import GridSearchCV
parameters = [{'C':[1, 10, 100], 'kernel':['linear']},
{'C':[1, 10, 100],
'kernel':['rbf'],
'gamma': [0.05, 0.001, 0.005]}]
grid_search = GridSearchCV (estimator = clf, param_grid = parameters, scoring = 'accuracy', cv = 10)
grid_search = grid_search.fit (X_train,y_train)
best_accuracy = grid_search.best_score_
print (best_accuracy)
best_parameters = grid_search.best_params_
print (best_parameters)
最佳答案
您必须对数据集进行SMOTE,并使用生成的平衡数据集进行建模训练。
因此,您必须像问题中未显示的代码那样加载数据,然后对其应用SMOTE。
就代码而言,可以这样完成
X = # train data
y = # train labels
# applying SMOTE
from imblearn.over_sampling import SMOTE
sm = SMOTE(random_state=42)
X_balanced, y_balanced = sm.fit_sample(X, y)
from sklearn.model_selection import train_test_split
X_train, X_test, y_train, y_test = train_test_split (X_balanced, y_balanced, test_size = 0.1)
from sklearn.preprocessing import StandardScaler
sc = StandardScaler()
X_train = sc.fit_transform(X_train)
X_test = sc.transform (X_test)
from sklearn.svm import SVC
clf = SVC(kernel = 'linear')
clf.fit (X_train, y_train.ravel())
y_pred = clf.predict(X_test)
from sklearn.metrics import confusion_matrix
cm = confusion_matrix (y_test, y_pred)
from sklearn.model_selection import cross_val_score
accuracies = cross_val_score (estimator = clf, X = X_train, y = y_train, cv = 10)
accuracies.mean()
accuracies.std()
from sklearn.model_selection import GridSearchCV
parameters = [{'C':[1, 10, 100], 'kernel':['linear']},
{'C':[1, 10, 100],
'kernel':['rbf'],
'gamma': [0.05, 0.001, 0.005]}]
grid_search = GridSearchCV (estimator = clf, param_grid = parameters, scoring = 'accuracy', cv = 10)
grid_search = grid_search.fit (X_train,y_train)
best_accuracy = grid_search.best_score_
print (best_accuracy)
best_parameters = grid_search.best_params_
print (best_parameters)
关于machine-learning - ML分类中的SMOTE,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/51299224/