Table 1.
DID model.
| Before change | After change | Difference | |
|---|---|---|---|
| Group1 (Treat) |
E(Yt1) | E(Yt2) | ΔYt=E(Yt2)-E(Yt1) |
| Group2 (Control) |
E(Yc1) | E(Yc2) | ΔYc=E(Yc2)-E(Yc1) |
| Difference | ΔΔY = ΔYt-ΔYc |
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