sergiocorreia / reghdfe

Linear, IV and GMM Regressions With Any Number of Fixed Effects
http://scorreia.com/software/reghdfe/
MIT License
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omitted because of collinearity fixed effects model interaction #223

Open Aimeeli847 opened 3 years ago

Aimeeli847 commented 3 years ago

I try to use reghdfe run a fixed interaction effects model:

I set SD_CF as one independent variables, meanwhile set year fixed effects and its interaction with SD_CF (as fixed effects). but, after running my code, i recieve a note: note: SD_CF omitted because of collinearity. thus SD_CF is omitted on regression table, which is not what i want to see.

Does anyone know how to fix this problem. Many thanks.

my code: reghdfe SD_Invest SD_CF lag_Q QCF Firm_size FSCF SD_board_size BSCF board_Indep BICF, absorb(i.fyear##c.SDCF i.ff 48##c.SD_CF) vce(cluster gvkey)