Python source code: gradient_boosting_regression.py
from sklearn import ensemblefrom sklearn.metrics import mean_squared_error
# Fit regression model
params = {‘n_estimators‘: 500, ‘max_depth‘: 4, ‘min_samples_split‘: 1,
‘learning_rate‘: 0.01, ‘loss‘: ‘ls‘}
clf = ensemble.GradientBoostingRegressor(**params)
clf.fit(X_train, y_train)
mse = mean_squared_error(y_test, clf.predict(X_test))
print("MSE: %.4f" % mse)
原文：http://www.cnblogs.com/chaofn/p/4623152.html