Hi, I want to compare the coefficient on one variable (i.e. IndVar) from the regressions based on two subsamples .

reghdfe DepVar IndVar ControlVar Tone>Median, absorb(sic2 fyear) cluster(gvkey)
reghdfe DepVar IndVar ControlVar Tone<Median, absorb(sic2 fyear) cluster(gvkey)


I was suggested to use the following code:

gen byte largetone = Tone > Median if Tone < . reghdfe DepVar i.largetone##(c.IndVar c.ControlVar) , absorb(sic2 fyear) cluster(gvkey)

The test reported next to the interaction term between 1.largetone and lndVar is the test I am looking for.


1. As an alternative method, can I use the following regression and look at the coefficient of the interaction term?

reghdfe DepVar i.largetone (or any indicator variable used to identify subgroups)##c.IndVar ControlVar, absorb(sic2 fyear) cluster(gvkey)

Does this regression aim to achieve different goals compared to the one I was suggested initially?


2. If I want to run subsample regressions separately, such as the models below:

reghdfe DepVar IndVar ControlVar if tone>median_tone, absorb(sic2 fyear) cluster(gvkey)
reghdfe DepVar IndVar ControlVar if tone<median_tone, absorb(sic2 fyear) cluster(gvkey)

Do I need to put the variable, tone, in these regressions as a control variable?