Russ Roberts on localist studies

Econtalk host and George Mason University economics professor Russ Roberts wrote a post this week about the benefits from trade and the problems with the "Buy Local" movement:

There are of course many studies of “buy local” that find that the movement creates jobs, makes us richer and so on. These studies are poorly done. They leave out many factors that cannot be measured.They are done by advocates, sometimes misguided but sometimes trying to enrich themselves by making others think that buying local is good for everyone rather than just themselves.

I've been reading studies from Civic Economics and the Institute for Local Self-Reliance, the two sources for all of the studies I've seen referenced, and found some pretty dodgy errors. I plan to compile in a larger post at a future date.