What do you pass for the cv parameter in the sklearn method cross_val_score In sklearn, there is a method for cross validation called cross_val_score. One of the parameters of this method is 'cv'.

I understand in cross validation, there is no splitting the data into training and validation (70-30 split). Instead, you split the data into 'k' subsamples, then train it on the K-1 subsamples and validate using the kth sample.
And repeat it for each of the 'k' subsamples.

So is this cv = k, i.e the number of subsamples in which you split the training data?
It determines the splitting strategy used by sklearn.

The default (“none”) is 3-fold CV. 



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