Posted 1/29/2006 05:03:00 PM by Douglas

There are liars, damn liars, and then there are statisticians. I couldn't get that phrase out of my head as I was reading this new study claiming private school students scored lower on math tests than kids in public schools. Well, "scored" is a relative term, because the private school kids actually "scored" higher, but when you reduce the data the way theses guys did to take into account factors that would give private school kids lower scores, then you would be correct.

Though private school students have long scored higher on the national assessment, commonly referred to as "the nation's report card," the new study used advanced statistical techniques to adjust for the effects of income, school and home circumstances. The researchers said they compared math scores, not reading ones, because math was considered a clearer measure of a school's overall effectiveness.

The study found that while the raw scores of fourth graders in Roman Catholic schools, for example, were 14.3 points higher than those in public schools, when adjustments were made for student backgrounds, those in Catholic schools scored 3.4 points lower than those in public schools. A spokeswoman for the National Catholic Education Association did not respond to requests for comment.

And who conducted the survey? It was funded by The National Assessment of Educational Progress, the keeper of the DoE's statistics [and this study's findings can be found here].

Survey bias? Oh, I don't know. What would the DoE have to gain by claiming that private schools aren't any better (or actually worse) than government schools which are funded with confiscatory taxes paid by people that have absolutely no say in their funding, but also in choosing what schools their kids get to attend? Hmmm, that's a real noodle scratcher.