I'm training a binary classifier using time series cross-validation and a rolling window approach, resulting in $k$ test sets. I want to construct a cumulative uplift curve to evaluate the model.
I've considered simply pooling all the test sets together, but that could result in the same customer appearing $k$ times, which isn't ideal. On the other hand, creating $k$ separate uplift curves would be cumbersome.
I would appreciate any advice or insights on the best practices to handle this issue.