The Kauffman foundation has produced the results of its latest survey of economics bloggers. Included in the survey was a question at the request of Bryan Caplan that I found quite interesting. The survey asked:

The net externality of the birth of an additional child in the United States is… [POSITIVE, ZERO, or NEGATIVE]

The results show that a majority of econo-bloggers believe the externalities to be positive:

This begs the question of the externalities of immigrants. After all, positive externalities for natives probably don’t start appearing until after high school or college, and before that they are on average consuming far more than they produce.

Since the average immigrant age is around 30, that means when they’ve arrived they are already past the stage when they just consume society’s resources, and have begun producing externalities. Doesn’t this suggest that positive externality of immigrants is even larger than that for natives? If you’re going to claim that the average lower education level of immigrants reduces their externalities, keep in mind that immigrants are also more likely to be small business owners and PhDs than natives.

It’s interesting that when immigration is discussed economists quickly jump to the debate about the impact on native wages. I doubt that the 72% of economists above believe that the average externality of people is smaller than 6% of the wages of highschool dropouts, which is around the lowest credible estimate in the literature, so why don’t economists accept that externalities of immigrants trump wage effects and quickly move to arguing for more immigration?