I have a dataset with features such as last_visit_n_days_ago
, last_purchase_n_days_ago
. These features are unavailable for many rows, which might have an important predictive value. The question is what to put in these cells if I want to use a learning algorithm that does not support missing values.
My options are:
- super large number (e.g.
1e38
) to - the maximal number available for this database, plus some margin. What can be a good margin in this case
- something else