More Bickering

Two quick notes on Tyler’s comment on my recent post on vouchers.

First, whether the school or the parent is sent the check is irrelevant (this is a basic theorem in economics). My point, however, was that parents cannot add-on to the voucher amount – i.e. the Chilean system has extensive price controls. Another way of saying this is that in the Chilean system parents never spend any of their own money on the private (subsidized) schools. I think a good voucher system requires that on at least some margins parents spend their own hard-earned dollars on their children’s education.

Second, Tyler thinks that the most convincing evidence is that Chileans did not improve on an international scale. Actually this is the least convincing evidence and it illustrates my point about the power of HU’s tests. The private schools in Chile increased by about 20 percentage points over the relevant time frame. Suppose that private schools were better than public schools by 10 percent then the aggregate gain at the national level would only be 2 percent. Small exogenous decreases in the quality of the public schools could easily swamp this gain.