Explain cross-validation, both the process and why you do it.

Explain cross-validation, both the process and why you do it.



Answer: Cross-validation is an effective tool to measure the accuracy of your model and check to see if it is underfitting or overfitting. In addition, it is useful to determine the hyperparameters of the model. You will use cross validation to determine which parameters will result in lowest test error. It does this by splitting your data into multiple groups, then training your model some of the groups and validating it on another group.


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