I wish to apply 10 fold cross validation to my model (with a sample size of 90). I have one question troubling me.
Once I am ready with a full model, I would break the full data into 9:1 ratio- 9parts for training and 1 part of testing, and in the same way I would be testing all the parts in 10 rounds.
The question that is troubling me is that how would I take the variables in each of the rounds. The variables would not be same.
If I am not correct please give me the steps to choose the variables in this stage?