Sorry Mr. Krugman, you flunk unionizing 101

Paul Krugman, left wing journalist and Nobel prize in something, has really stepped into it now. He claimed that Texas children were doing more poorly than Wisconsin's who have the benefit of all those rich, well-pensioned, unionized teachers with collective bargaining rights.

However. . .

Texas students beat Wisconsin in every category when ethnicity is taken into account. See Iowahawk, who usually writes a humor column, but in this case is very serious.

"So how to compare educational achievement between two states with such dissimilar populations? In data analysis this is usually done by treating ethnicity as a "covariate." A very simple way to do this is by comparing educational achievement between states within the same ethnic group. In other words, do black students perform better in Wisconsin than Texas? Do Hispanic students perform better in Wisconsin or Texas? White students? If Wisconsin's kids consistently beat their Texas counterparts, after controlling for ethnicity, then there's a strong case that maybe Texas schools ought to become a union shop.

Luckily, there is data to answer this question via the National Assessment of Educational Progress (NAEP). The NAEP is an annual standardized test given to 4th and 8th graders around the country to measure proficiency in math, science, and reading. Participation is fairly universal; if you've had a 4th or 8th grader in the last few years, you're probably familiar with it. Results are compiled on the NAEP website, broken down by grade, state, subject and ethnicity."