Boosting contest: Light vs Extreme
While the performance of the CatBoost model is relatively good, let's try two other flavors of boosting and see which performs better: the "Light" or the "Extreme" approach.
CatBoost is highly recommended when there are categorical features. In this case, all features are numeric, therefore one of the other approaches might produce better results.
As we are building regressors, we'll use an additional parameter, objective, which specifies the learning function to be used. To apply a squared error, we'll set objective to 'reg:squarederror' for XGBoost and 'mean_squared_error' for LightGBM.
In addition, we'll specify the parameter n_jobs for XGBoost to improve its computation runtime.
OBS: be careful not to use classifiers, or your session might expire!
Bu egzersiz
Ensemble Methods in Python
kursunun bir parçasıdırEgzersiz talimatları
- Build an
XGBRegressorusing the parameters:max_depth = 3,learning_rate = 0.1,n_estimators = 100, andn_jobs=2. - Build an
LGBMRegressorusing the parameters:max_depth = 3,learning_rate = 0.1, andn_estimators = 100.
Uygulamalı interaktif egzersiz
Bu örnek kodu tamamlayarak bu egzersizi bitirin.
# Build and fit an XGBoost regressor
reg_xgb = ____.____(____, ____, ____, ____, objective='reg:squarederror', random_state=500)
reg_xgb.fit(X_train, y_train)
# Build and fit a LightGBM regressor
reg_lgb = ____.____(____, ____, ____, objective='mean_squared_error', seed=500)
reg_lgb.fit(X_train, y_train)
# Calculate the predictions and evaluate both regressors
pred_xgb = reg_xgb.predict(X_test)
rmse_xgb = np.sqrt(mean_squared_error(y_test, pred_xgb))
pred_lgb = reg_lgb.predict(X_test)
rmse_lgb = np.sqrt(mean_squared_error(y_test, pred_lgb))
print('Extreme: {:.3f}, Light: {:.3f}'.format(rmse_xgb, rmse_lgb))