Hello! I am attempting to estimate a model using a panel of data that includes between 1 and 13 years of observations for over 40,000 households (i.e. unbalanced). The data is well-suited for Poisson or negative binomial models, but given that it only includes positive values for the outcome, I think zero-truncated models would be best. I don't see an option within the xtpoisson/xtnbreg suite to account for the zero truncation. Similarly, for the ztp and ztnb, I don't see a way to do fixed effects other than to hard code them as dummy variables. Unfortunately that seems to cause a problem with my max variables because the panel is rather large. I can try bootstrapping, but I'm wondering if there's another way. Any advice is very much appreciated.