Appreciate the detailed information. Yes , that is the theory of k fold cross-validation.
I think I confused you the question.
My question is :
1. We have a model already(we need dataset to find our final model, let’s say this process we use dataset A ).
2. Then we need to assess predicting performance of our model. We can use k fold cross-validation to do it. During this process, we still need dataset, let’s say this process we use dataset B.
The question is what is dataset A, and what is dataset B ?
For example, A and B come from the same original dataset? Let ‘s say 70% of original dataset used for A, and 30% of original dataset used for B?
That is what I want to ask, help it is much clear now.