Hope you are enjoying the coziness of the weekend or early Monday already!.
I have a data set with two by two-way design. I got the overall difference-in-difference effect from regression, but I am not certain what is the best way to write a syntax to get multiple DID effects of each subgroup.
The model is about the change of Grade Point Average in Time 0 and Time 1 between controlled and treated groups. I am more interested, however, in the changes of GPA in each race/ethnicity & gender (i.e, female African, male African, female Hispanic, male Hispanic, female White, male White, and more).
The interpretation of coefficients is not a big deal when I have a dummy variable of gender. However, I am getting lost as the model has many dummy variables of gender and race/ethnicity in addition to the DID effect. Should it be the best way to define subgroups and run regression multiple times to get DID effects of a subgroup? or is there a better idea I can borrow?
regards,

Model I used to have Overall DID effect:
reg GRADE_POINT i.T##i.TREATED [pw = CREDIT_HR]
Model i am considering to use for DID effect of each subgroup:
reg GRADE_POINT i.T##i.TREATED [pw = CREDIT_HR] if GENDER == [value] & RE == [value]


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Code:
* Example generated by -dataex-. For more info, type help dataex
clear
input double PIDM float(T TREATED) byte(GENDER RE) str5 CRN float GRADE_POINT double CREDIT_HR
604323 0 0 1 7 "40002"   0 3
611455 0 0 1 7 "40002" 2.7 3
612230 0 0 1 7 "40003" 3.7 3
607659 0 0 0 5 "40003"   2 3
603693 0 0 0 7 "40003" 2.7 3
611084 0 0 1 7 "40003"   2 3
604251 0 0 0 7 "40003"   0 3
609437 0 0 1 5 "40004"   2 3
604487 0 0 1 7 "40004"   0 3
604836 0 0 1 7 "40004"   2 3
603273 0 0 1 7 "40004" 3.7 3
606161 0 0 0 5 "40006" 2.7 3
615142 0 0 0 5 "40006"   2 3
606312 0 0 1 7 "40006" 1.7 3
606242 0 0 0 7 "40007" 2.7 3
612811 0 0 0 5 "40007" 1.7 3
605898 0 0 1 5 "40009" 2.7 3
608254 0 0 0 7 "40010"   4 3
610725 0 0 1 7 "40011"   2 3
603484 0 0 0 5 "40012"   0 3
603611 0 0 0 2 "40013" 3.3 3
606323 0 0 0 7 "40013" 3.7 3
611313 0 0 0 7 "40013" 1.7 3
606587 0 0 0 7 "40014"   4 3
607473 0 0 1 7 "40014" 3.7 3
613507 0 0 0 7 "40016"   4 3
604475 0 0 0 7 "40017" 3.7 3
606806 0 0 0 7 "40018"   3 3
610340 0 0 0 7 "40019"   4 3
616039 0 0 0 5 "40019"   3 3
end
label values T T
label def T 0 "T0", modify
label values TREATED TREATED
label def TREATED 0 "Controlled", modify
label values GENDER GENDER
label def GENDER 0 "Female", modify
label def GENDER 1 "Male", modify
label values RE RE
label def RE 2 "Hispanic/Latino", modify
label def RE 5 "Black or African American", modify
label def RE 7 "White", modify
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