Questions about channel-attribution-lstm

[NataliaVConnolly]

Hi Ilya,

First, thanks so much for putting together this really helpful repo!

I've been trying to understand channel-attribution-lstm, and I've got a couple of questions about your features_for_lstm function.

1. This code here:
   f_proj = df[['jid', 'campaigns', 'cats', 'click', 'cost', 'time_since_last_click_norm', \ 'timestamp_norm', 'conversion']]
x2d = df_proj.values
x3d_list = np.split(x2d[:, 1:], np.cumsum(np.unique(x2d[:, 0], return_counts=True)[1])[:-1])

Won't this split only work as intended if f_proj is sorted out by jid first? If the goal here is to separate out the sub-arrays for individual jids? Or am I missing the point?

3. journey_matrix = journey_matrix[ journey_matrix[:, 5].argsort() ] # sort impressions by timestamp

Why 5 here? The timestamp_norm field is next to last in the journey_matrix array, so shouldn't it be journey_matrix.shape[1]-2?

4. Finally, I had to convert y_train, y_val, and y_test into arrays for the model to run; it wouln't work for me as written because they were lists.

   I'd really appreciate your help! Thank you again --
   Natalia