Hi everyone,
I make a comparison of the impact of variable X on Y before and after the Covid19 pandemic using panel data (2000-2021), and plan to use the DiD model.
I did a test, choosing year=2019 as the benchmark. create variable t with the command: gen t=(year>=2019) means assigning 0 is the period from 2000-2018 as pre-Covid; 1 is the period 2019-2021 as post-Covid.
But I don't know how to create the Treat variable appropriately? I have tried many ways to create the Treat variable, but the regression results do not appear the coefficients (omitted) of the treat and treat*time variables.
Please help me
I make a comparison of the impact of variable X on Y before and after the Covid19 pandemic using panel data (2000-2021), and plan to use the DiD model.
I did a test, choosing year=2019 as the benchmark. create variable t with the command: gen t=(year>=2019) means assigning 0 is the period from 2000-2018 as pre-Covid; 1 is the period 2019-2021 as post-Covid.
But I don't know how to create the Treat variable appropriately? I have tried many ways to create the Treat variable, but the regression results do not appear the coefficients (omitted) of the treat and treat*time variables.
Please help me
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