We examine the effect of shocks to teacher inputs on child performance in school. We start with a household optimization framework where parents spend optimally in response to teacher and other school inputs. This helps to isolate the impact of teachers from other inputs. As a proxy measure for...

Most studies fail to find an impact of school inputs on outcomes such as test scores. We argue that this might be a consequence of ignoring the possibility that households respond optimally to changes in school inputs and thus obscure the real effect of such provision on cognitive achievement....

What drives migration and remittance behaviour in South Africa, and what are the implications for public policy? This paper evaluates existing empirical evidence, posits a simple theoretical model and undertakes a fresh evaluation using longitudinal data spanning 1993 to 2004 from KwaZula-Natal...

This paper shows how to derive a complete set of optimality conditions characterising the solution to a dynamic optimal income tax problem in the spirit of Mirrlees (1971), under the assumption that a 'first-order' approach to incentive compatibility is valid.  The method relies on constructing...

Climate change must deal with two market failures, global warming and learning by doing in renewable use. The social optimum requires an aggressive renewables subsidy in the near term and a gradually rising carbon tax which falls in long run. As a result, more renewables are used relative to...

What kind of tariff reform is likely to raise welfare in situations where tariff revenue is important?  Uncertainty about specification and risk from imprecise parameter estimates of any particular specification reduce the credibility of simulation estimates.  A promising alternative is to...

Demand for oil is very price inelastic.  Facing such demand, an extractive cartell induces the highest price that does not destroy its demand, unlike the conventional Hotelling analysis: the cartel tolerates ordinary substitutes to its oil but deters high-potential ones.  Limit-pricing...