July 25, 2011 § Leave a comment
As proof, instrumental variable approaches are basically useless, because even attacks from people who don’t really get that correlation isn’t causation are difficult to dismiss.
I’m willing to say IV estimates, when assumptions are close to met, are better than naive regressions, but how much better? I need to look at whatever work has been done on the robustness of IV estimates.
(edit: I don’t think the Tragedy of the Commons is the biggest issue, but it also deserves further consideration)
July 22, 2011 § Leave a comment
I’ve been busy working on publications for once, but I couldn’t help but reproduce this breathtaking graph from the Heritage blog:
The fact that it’s piecewise-linear (edit: piecewise-quadratic, really) is bad enough, and that’s only the fourth-worst thing about it.