Dana Goldstein of the American Prospect blogs that “research clearly shows that students using vouchers perform no better academically than their socio-economically similar peers in public schools.” This is flamboyantly false.

I recently reviewed the literature comparing public, private, and truly free market school systems, and an expanded version of that study is forthcoming in the Journal of School Choice. The JSC version tabulates the findings of 65 scientific studies (including every U.S. and foreign voucher study I am aware of), collectively reporting 156 comparisons of educational outcomes. What does the research “clearly show”? It shows this:

Summary of Findings Comparing Private and Government Schooling,
by Result and Outcome Category

The above table summarizes the results of the scientific literature, showing the number of findings favoring the private sector by a statistically significant margin, the number that are insignificant, and the number favoring the public sector by a statistically significant margin. It does this for all eight available outcome measures: academic achievement, efficiency (achievement per dollar spent per pupil), parental satisfaction, the orderliness of classrooms, the condition in which facilities are maintained, the later earnings of graduates, the highest school grade or degree completed, and effect on measured intelligence. And it incontrovertably shows that private sector outperforms the public sector in education across all of those measures.

But there’s more. As I note in the conclusion: “It is in fact the least regulated market school systems that show the greatest margin of superiority over state schooling.” When the above results are winnowed down so that we compare only free markets of private schools that are funded at least in part directly by parents to public school monopolies like those of the United States, the findings are even more starkly divided:

Note the staggering overall results. Findings favoring free market school systems outnumber contrary findings by a margin of 15 to 1. They also outnumber the combined insignificant findings and the findings favoring monopolies by more than 3 to 1. Most tellingly, when we look at efficiency we find that there are NO results in the literature that favor government schooling and NO results that are statistically insignificant. EVERY study that compares academic achievement per dollar spent per pupil between market school systems and public school systems finds a significant market advantage.

Goldstein and The American Prospect should obviously print a retraction. But if they are interested in the truth, they might want to do something more. They might want to ask themselves why they continue to cling to a monopoly system that has been overwhelmingly discredited in the scientific literature.…