Cross validating simple flight duration model

You've already built a few models for predicting flight duration and evaluated them with a simple train/test split. However, cross-validation provides a much better way to evaluate model performance.

In this exercise you're going to train a simple model for flight duration using cross-validation. Travel time is usually strongly correlated with distance, so using the km column alone should give a decent model.

The data have been randomly split into flights_train and flights_test.

The following classes have already been imported: LinearRegression, RegressionEvaluator, ParamGridBuilder and CrossValidator.

Create an empty parameter grid.
Create objects for building and evaluating a linear regression model. The model should predict the "duration" field.
Create a cross-validator object. Provide values for the estimator, estimatorParamMaps and evaluator arguments. Choose 5-fold cross validation.
Train and test the model across multiple folds of the training data.

Exercise

Cross validating simple flight duration model

Instructions