Hi everyone !
In my research, I am looking at the effect of some policy (say X) on bilateral trade flows. However, the effect of such non-discriminatory policies may actually be quiet heterogeneous across sectors. Therefore, I want to estimate the structural gravity model at disaggregated sectoral level. After merging the data on exporter and importer variables from multiple sources, I am using the following codes to create such panel data set :
Code:
 egen pair_id = group (Importer Exporter Sector)
Code:
 
xtset pair_id Year
In this panel each observation gives Imports of country (i) from country (j) in sector (s) at year (t) .
I want to ask , is this a correct way to create a panel for estimating sectoral level Gravity Model ?
Please reply,
Thanks