SLOPPY EDUCATION RESEARCH (1)

Opponents of school choice have just released two major studies claiming to show that public schools actually perform better than private schools. One study made the front page of the New York Times. Unfortunately, both of them are seriously flawed. What’s more, a much larger body of much better studies reaches the opposite conclusion. The studies were released within about a week of each other, and by the same organization: the National Center for the Study of Privatization in Education. While this may have made it a good week for the center in terms of publicity, it was an awful week in terms of scientific credibility.

The first study found that when you control for demographic factors like race and income, public school students actually have higher test scores than private school students. The authors have been aggressively touting this study as though it showed that public schools were better than private schools. In fact, it shows nothing of the kind. They take snapshots of student achievement in isolated years rather than tracking achievement over time. That may not sound important, but it’s crucial. If you don’t track students over time, you can’t find out why one student has a higher score than another. Single-year test scores mostly reflect student quality, not school quality. A student with high test scores is usually just a good student. It takes a student whose test scores are rising to prove that the school is good.

A much more likely explanation for these data is that the students who enter private schools tend to be slightly worse students than those of the same race and income who enter public schools. That makes perfect sense, because within each racial and socioeconomic group it’s the low performers whose parents will want to make the sacrifices necessary to put them in private schools.

The other study looked at Cleveland’s ten-year-old voucher program. Using a new statistical model to analyze a previously existing data set, it finds that kids remaining in Cleveland public schools do better than voucher users. This study is even more flawed than the previous one. The data set it analyzes does not allow for valid comparisons between similar student populations. The voucher students and the public school comparison groups in the data set are dissimilar not only because one group uses vouchers and the other doesn’t, but also in a host of other ways, and there’s no way to disentangle what’s really causing the test score difference. The study compares apples and oranges.

As it happens, numerous studies that avoid these methodological problems find that private schools do better. Most convincing are seven studies that compared students who won a random lottery to use a school voucher at a private school to similar students who lost the lottery and stayed in public schools. All seven found that voucher kids did better. Studies using other methods also favor private schools overwhelmingly.

Not all of the work sponsored by this organization is as bad as these two studies. It has promoted good, solid research showing that competition from school choice improves public schools. That’s even more impressive given that it’s housed at Columbia University’s Teachers College, the greatest academic stronghold of the teacher unions anywhere in the nation. But the center also has a dark side. From time to time it will release badly flawed studies purporting to show the inferior performance of private schools. With these two studies, it has just had probably its worst week ever. Let’s hope this misleading research doesn’t distract from the real scholarly consensus finding that private schools do better, and that school choice works.

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SLOPPY EDUCATION RESEARCH (2)

Post lifted from The Locker Room

Douglas Reeves, CEO and founder of the Center for Performance Assessment, comments on a recent study by Peggy Hsieh and Joel R. Levin published in the Journal of Educational Psychology. Hsieh and Levin showed that only a small percentage of education research uses a randomized experimental design (random assignment to control and experimental groups), and over the years, the percentage has been decreasing.

They point to two reasons for this. The first is a growing preference for qualitative research, a product of post-modernism and relativism in the academy. The second reason is that, empirical research is difficult to conduct and yields unpopular results, many authors simply take their studies down an easier path. I think the latter explanation is key

Recently, I wrote a Spotlight on the failure of class size reductions in low income and low performing elementary schools. The evaluation team used an experimental design to assess the class size reduction program and found that the experimental group did no better than the control group. Needless to say, these results were unpopular, so unpopular, in fact, that the State Board of Education did not post the entire report on its website.

The significance of research design is lost on those who compared the state's program with other research that has been done on small class sizes. But the problem is not the critics but the education researchers who have done even more to diminish the credibility of the profession.

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For greatest efficiency, lowest cost and maximum choice, ALL schools should be privately owned and run -- with government-paid vouchers for the poor and minimal regulation.

The NEA and similar unions worldwide believe that children should be thoroughly indoctrinated with Green/Left, feminist/homosexual ideology but the "3 R's" are something that kids should just be allowed to "discover"

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