This paper uses data from a randomized social experiment in Mexico to estimate and validate a dynamic behavioral model of parental decisions about fertility and child schooling, to evaluate the effects of the PROGRESA school subsidy program, and to perform a variety of counterfactual experiments...

An incentives based theory of policing is developed which can explain the phenomenon of random "crackdowns," i.e., intermittent periods of high interdiction/ surveillance. For a variety of police objective functions, random crackdowns can be part of the optimal monitoring strategy. We...