Hello, Statalist
Something not clear for me in the results after using the module JMPIERCE2.
For example:
I have the estimated wage for four groups : two in Israel and two in Germany.
In each country one group is natives and second group is immigrants.
So four groups:
1) ISR_NAT
2) ISR_IMM
3) GER_NAT
4) GER_IMM
If I want to decompose difference in difference:
D = [(D ISR_NAT - D ISR_IMM) - (D GER_NAT - D GER_IMM)]
Is it my command right:
reg wage hour age educ if isr_nat==1
est store isr_nat
reg wage hour age educ if isr_imm==1
est store isr_imm
reg wage hour age educ if ger_nat==1
est store ger_nat
reg wage hour age educ if ger_imm==1
est store ger_imm
jmpierce2 isr_nat isr_imm ger_nat ger_imm, benchmark(1)
Which order of estimators in command jmpierce2 is right for my decomposition?
If I change to the parameter benchmark(2), the total difference is same. Why?
What is the role of parameters "benchmark" and "reference" in my order
of estimators: isr_nat isr_imm ger_nat ger_imm?
Thank you in advance for your help,
Michael
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