MixedThe Wall Street JournalWhile it’s good to look to the data, the book also demonstrates the limitations of research ... On topics such as school choice, Ms. Oster points to hard metrics like class size and test scores, but these come with their own cans of worms. For instance, a mediocre school can have good test scores if it is in a wealthy district where many children get private tutoring, while a terrific school that takes in struggling students may have low average test scores despite having a positive effect on its students. Moreover, what little data-driven guidance exists for school choice comes with some major caveats. Studies have little to say about which school will make your child happy or well adjusted ... Part of the challenge is the social-science research upon which the book draws is often conducted with a heavy emphasis on policy evaluations, which can lead to blind spots when it comes to helping people make better decisions ... Ms. Oster’s book serves as a reminder of both the value of research and the need for much more of it.
