P2 and Y2 are not shown because their descriptions imply that they're lags, and lags are handled in the model specification dialog by the apparatus you get by clicking on the "lags...". However, in your dataset those "lag-type descriptions" are misleading. If you change (or remove) their descriptions they will appear in the selection dialog.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I accept that this is a bug: gretl is jumping to a false conclusion about the status of P2 and Y2 in this case. The code for determining whether a given series is a lag of some other series needs to be made more rigorous.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
P2 and Y2 are not shown because their descriptions imply that they're lags, and lags are handled in the model specification dialog by the apparatus you get by clicking on the "lags...". However, in your dataset those "lag-type descriptions" are misleading. If you change (or remove) their descriptions they will appear in the selection dialog.
I accept that this is a bug: gretl is jumping to a false conclusion about the status of P2 and Y2 in this case. The code for determining whether a given series is a lag of some other series needs to be made more rigorous.
This now fixed in gretl git. New snapshots will follow before long.