Hi,

I am using the ppml_panel_sg estimator for a gravity model with fixed effects (exporter-time, importer-time and pair) :

ppml_panel_sg trade x1 x2 x3 if exporter != importer, ex(exporter) im(importer) y(year) cluster(pairid)

I would like to know how could I use the same estimator but for: exporter-fixed effect, importer fixed effect and year-fixed effect.

Thanks!