Caroline M. Hoxby
2003
Hoxby presents a compelling report on the impact of three choice programs - Milwaukee's vouchers, and Michigan and Arizona's charter schools - on school productivity and student achievement. She limits her study to these three because they are the only choice programs that meet her strict criteria for competition effects - that is (in addition to offering sufficient data), they introduce true competition by allowing a substantial amount of money to follow the student; allow for changes in the number of schools (i.e. a "supply effect"); and do not place the choice program under the supervision of the schools with which it competes. She finds that schools in these three locales that faced competition did improve their productivity (test scores divided by per pupil spending). This remained true when controlling for a host of factors, including pre-existing trends and "creaming" (which wasn't actually a factor). The lay reader will also be interested in some of Hoxby's general observations - for example, that school productivity in the United States has declined some 50 percent since 1970, even after controlling for differences in students and changes in teacher salaries. She also comments on the recent controversy regarding Peterson's analysis of the New York City voucher program, in which he found positive results for black students - only to have Krueger and Zhu note flaws in the analysis. Hoxby suggests that those two fished for the results they wanted by "arbitrarily" assigning race classifications in violation of "standard social science practice." And she sheds some light on why the only positive results were found for black students - namely, that there were differences in the samples because the reform was aimed at helping black students. In other words, choice programs might work for the population they are intended to help, mirabile dictu. Her analysis is rigorous, yet her writing is straightforward. Well worth attention. Find it online at http://www.ekradet.konj.se/sepr/SEPRvol10Nr2/Hoxsby.pdf.