O’Reilly and Math

Diane and I are visiting the breeders from whom we bought Ritka, our young Vizsla. A copy of Bill O’Reilly’s Culture Warrior book was on the kitchen table, and I couldn’t resist having a look at his comments on education.

And my outrage threshold was crossed with the following comment by O’Reilly.

Want more evidence that S-P [secular-progressive] opposition to school vouchers damages kids? Try this: In Washington, D.C., according to the National Center for Education Statistics, public school spending on each pupil is now over $10,000 per child per year, an astounding amount and about double what it was thirty years ago. D.C. Catholic schools spend far less per pupil than the public schools do. And — you guessed it — test scores for the Catholic school kids are far higher than those for the public school students. In fact, 98 percent of kids graduating from D.C. Catholic schools go on to college, while almost 40 percent of D.C. public school students never graduate from high school; they drop out. Once again, the math tells the story. Too bad so many public school kids will never learn how to do math.

Uh, Bill, I’m not sure how to break this to you, but based on the evidence of the above paragraph, you haven’t proven that you know how to do math, either. Or use logic, for that matter.

I’m fully prepared to believe that, in general, private Catholic high schools are fine places to obtain a good education. I graduated from one myself, and I did learn a fair bit of math there. I also know that my admission to the school was premised upon my prior record of performance and passing an entrance examination. This selection effect is a confounding factor that means that a direct comparison of a few numbers from public schools and Catholic schools will not necessarily be telling you anything interesting about the topic of interest, which is how much any arbitrary student entering one or the other will learn from the school. Since Catholic schools generally only accept students with high performance expectations in the first place, one expects that their students will do well upon graduation, too. I recall a story in Smithsonian magazine concerning a specialized math and science high school in Boston. There was a paragraph that did detail the rigorous admission standards, such that they only took in the top 2 percent of students applying. Later in the article, the author expressed enthusiasm for the 99 percent figure for graduating students going on to college, but as far as I’m concerned, the selection effect is a completely adequate explanation in both cases.

But a further problem with O’Reilly’s “analysis”, if we may stretch the word a bit, is that he doesn’t bother to provide us with numbers that we could do math upon. For one class of schools, Bill gives us the percentage of graduating students who go on to college. Bill does not provide us with the same figure for the other class of school. I expect that’s because it wouldn’t make the same visceral contrast that Bill wishes to paint concerning the situation. For the other class of school, Bill tells us the percentage of students who drop out. Is Bill confused? Is the merit of a class of school in the proportion of students who go on to college after graduation, or is it in the proportion of students who make it to graduation? If Bill were being coherent and mathematically consistent, he’d have stuck to numbers about one or the other, or provided numbers from each class of school on each proposed measure of merit. Instead, we’re getting apples and oranges from Bill, and the resulting mash is a mess. I know for a fact that students do indeed drop out of Catholic high schools; I’ve seen it happen. I know for a fact that a substantial proportion of public high school graduates go on to college; I have studied alongside them.

I have another problem with Bill’s rhetoric, which is in the way the numbers, incomparable as they are, are presented to the reader. Bill tells us that “98” is a good thing, and then that “40” is a bad thing. Even putting aside the fact that the numbers aren’t on the same scale at all, if Bill were being consistent, he’d either report both “good” numbers (98 and 60) or both “bad” numbers (2 and 40), but not a mix of “good” and “bad” numbers to further confuse his reader. I suspect that confusing the reader, though, is exactly the effect that Bill was pursuing. This sort of shady dealing with numbers is covered in detail in Huff’s How to Lie With Statistics.

What about that per-child expenditure figure? Well, the selection effect goes some way to explaining that, too. Public schools cannot be selective; private schools can. A private school need not admit special-needs students; public schools must budget to accommodate special-needs students. And special services for special needs will increase budgets in a non-linear fashion.

We don’t even have to go to O’Reilly’s favored factor for the difference in classes of schools, discipline, in order to see that Bill has failed to make his case. Knowing something about the math, as I learned it in Catholic high school, means that I look at Bill’s rhetoric and see a culture warrior adrift without a clue. If he attended Catholic high school, he could have used a bit more knuckle-rapping with a ruler in math class, I guess.