JWDID and Not Yet Treated Pre-trends

[Salvatore Fittizio]

Hi!
I am trying to run JWDID with not yet treated as controls, and at the same time have pretreatment coefficients for parallel trend assumption.
I first calculate IPWs using, e.g. for treated cohorts 2014, the units in cohorts [2015,2025]. Cohorts [2023,2025] are recoded as never treated and they only function as control cohorts. Then, I try to use JWDID, but if I use the 'never' option, cohorts [2023,2025] are the only controls used, while if I remove it I cannot have pretreatment coefficients as the command assumes that parallel trends hold. Considered that I have a count variable on the left hand side (patent count), that the treatment is staggered, and that I would like to use the ppmlhdfe, what are my options? Maybe toremove 'never' and do an ad-hoc event study on the side to complement it?

Thank you and have a nice day.

Salvo

[FernandoRios]

You need NEVER to get pre-treatment trends
If you do not have any Never treated, you can always constrain your window and use units treated last as your never treated (as long as your last period is before those units were treated.
Otherwise, your alternative solution is to do the same, but for rolling dates. That way you can maximize your "control" set of Not yet treated (but treated as never treated)

HTH