Exercise

Evaluate the training error

You'll now evaluate the training set RMSE achieved by the regression tree dt that you instantiated in a previous exercise.

In addition to dt, X_train and y_train are available in your workspace.

Instructions

100 XP

Import mean_squared_error as MSE from sklearn.metrics.
Fit dt to the training set.
Predict dt's training set labels and assign the result to y_pred_train.
Evaluate dt's training set MSE and assign it to RMSE_train.

Take Hint (-30 XP)