Hi,

I want to compare the treatment effect on the patent quantity produced by treatment and control group. The dependent variable is lnpatent (log value of patent )and there is no other predictors. Without synthetic matching my equation looks like this:

reghdfe lnpatent treatment##post, a(assignee appyear) vce( cluster assignee)

Now for the synthetic matching, I want to match treatment and control firms based on Pre-Intervention Outcomes ONLY. As I have multiple treatment groups I have created one dummy variable called interact with the interaction of treatment and post. The code I'm using is:

synth_runner lnpatent lnpatent(1970) lnpatent(1972) lnpatent(1974), d(interact)

and its showing me the following error:

. synth_runner lnpatent lnpatent(1970) lnpatent(1972) lnpatent(1974), d(interact)
(9834 missing values generated)
Estimating the treatment effects
Error estimating treatment effect for unit 1045
Re-running last -synth- command with output/errors un-captured
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Synthetic Control Method for Comparative Case Studies
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First Step: Data Setup
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invalid numlist has too few elements
r(122);

Any help is appreciated.

Regards,

Syeda