How Can We Tell If Vouchers "Work"?
Brookings recently released an evaluation of New York City’s voucher program, called the School Choice Scholarship Foundation Program (SCSF), which was implemented in the late 1990s. Voucher offers were randomized, and the authors looked at the impact of being offered/accepting them on a very important medium-term outcome – college enrollment (they were also able to follow an unusually high proportion of the original voucher recipients to check this outcome).
The short version of the story is that, overall, the vouchers didn’t have any statistically discernible impact on college enrollment. But, as is often the case, there was some underlying variation in the results, including positive estimated impacts among African-American students, which certainly merit discussion.*
Unfortunately, such nuance was not always evident in the coverage of and reaction to the report, with some voucher supporters (strangely, given the results) exclaiming that the program was an unqualified success, and some opponents questioning the affiliations of the researchers. For my part, I’d like to make a quick, not-particularly-original point about voucher studies in general: Even the best of them don’t necessarily tell us much about whether “vouchers work."