Re: st: DiD

[federico.tedeschi@univr.it]

So, you have this regression:

> regress  y treat post05  treat_post05 [aweight=hhweight],r cluster(ea)

with a dataset like this:

> id year y   program   treat  post05  treat_post05
1 2000 10 0 0 0 0
2 2000 20 0 0 0 0
3 2000 30 0 0 0 0
4 2000 40 0 1 0 0
5 2000 50 0 1 0 0
6 2000 60 0 1 0 0
1 2007 70 0 0 1 0
2 2007 80 0 0 1 0
3 2007 90 0 0 1 0
4 2007 100 1 1 1 1
5 2007 110 1 1 1 1
6 2007 120 1 1 1 1
7 2007 130 0 0 1 0
8 2007 140 0 0 1 0
9 2007 150 0 0 1 0

and treat*post05 is dropped? 
I think you could try to see how things changes if you change the weights, or omit treat (or post05) or the clusters, and also see how much treat*post05 is correlated with treat and post05.
Federico  
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