Tuesday, July 1, 2008

Goldwater Institute: Controlling for Demographics is Fantasy

Matt Ladner, Ph.D.

One of the quasi-myths of Arizona education is that Arizona performance is average if you control for demographics. It is a quasi-myth because it is true but misleading.

The claim is based upon a report by the RAND Corporation. What people seem to fail to appreciate is what a gigantic leap "controlling for demographics" represents.

If you statistically pretend that Arizona has an English language learner population that is one fourth its actual size, and about half the number of low-income children than we actually have, you are getting there. If you also make some additional heroic assumptions, Arizona's adjusted scores are near the middle instead of close to the bottom. Ergo, Arizona schools are of average rather than bottom quality. Fair enough.

In terms of what our future workforce will know and be capable of doing, controlling for demographics can only be described as a fantasy. In the real world, you don't get to "control for demography." In the real world, 44 percent of Arizona fourth graders can't read. In the real world, low-income Hispanics in Florida outscore the average Arizona fourth grader in reading.

Buy that myth? If so, I've got a bridge I'll sell you in Lake Havasu--cheap!

Dr. Matthew Ladner is vice president of research and director of the Center for Educational Opportnity at the Goldwater Institute.

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