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synth-inference / synthdid

Synthetic difference in differences
https://synth-inference.github.io/synthdid
BSD 3-Clause "New" or "Revised" License
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Large estimates #93

Open boicemw opened 2 years ago

boicemw commented 2 years ago

After including controls the level of my estimate jumps somewhere in the realm of 6e+20. The outcome I am looking at is variance of GDP, which is large but not to that order of magnitude. Before controls it is more reasonably 1e+06. Any help?

skranz commented 2 years ago

Using Monte-Carlo simulations, I also found that in some cases synthdid with controls does not seem to work well. A short description of the issue and an alternative approach of dealing with control variables is described here:

https://github.com/skranz/xsynthdid/blob/main/paper/synthdid_with_covariates.pdf

See also the main page of corresponding xsynthdid package for examples and installation instructions:

https://github.com/skranz/xsynthdid/

Perhaps that alternative approach might help.