In many countries welfare services that traditionally have been provided by the public sector are being contracted out to private providers. But are private contractors better at providing these services? We use a randomized experiment to empirically assess the effectiveness of contracting out...

Many comparisons of the performance of public and private producers use a public/private ownership dummy variable to capture cost differences in cross section data. This is appropriate if the producer choice is random. The dummy variable model is, however, logically inconsistent if the producer...