Thursday, May 18, 2006

When Good Economists Go Bad 

We've got to come up with a simple term describing an economist whose brain shuts down when he thinks about immigration. Tyler Cowen of Marginal Revolution is currently the leading example. He's very smart about a lot of stuff but he when he starts trying to think about immigration, he seems to get stuck in some sort of ideological rut. Every data point that seems to support massively increasing immigration strikes him as very important and every contra-indicator, well, I'm not sure he's able to see them at all.

Steve Sailer has done a good job at pointing out how Cowen's getting whacked by readers in the comments to his own blog, so I'll won't into the details here. Instead, let me point out that Cowen's most recent post points to Bryan Kaplan's EconLog post arguing that being around a lot of immigrants makes people less worried about immigration. Or as he puts it: "Direct observation of immigrants leads to more reasonable beliefs about the effects of immigration."

More reasonable, huh? Well, that's a question begging restatement of the issue if I ever heard one. But that's not my point.

Kaplan's also getting whacked by readers. A poster called "Teller" has pointed out that if you control for income, the significance of immigration vanishes all together. "The average state income is however significantly correlated people with being positive towards immigration," Teller writes. This is exactly what you would suspect since the poor feel the costs of immigration much more the those on the upper end of the income scale.

Another problem with Kaplan's contention is that it fails to take into account the fact that people move, and (not insignificantly) people move out of areas experiencing large influxes of immigration. Economics call this the "immigration push" effect. A lot of people who live in areas with few immigrants live there because they've moved away from areas with lots of immigrants. So it's not as simple as where people live determining their opinions about immigration; people's opinions about immigration also determine where they live.

Here's more on the immigration push effect.