Some education policymakers focus on bringing down pupil-teacher ratios. Others argue that resources will have limited impact without systematic reforms to education governance, teacher incentives, and pedagogy. We examine a program under which Kenyan Parent-Teacher Associations (PTAs) at...

We argue that in pharmaceutical markets, variation in the arrival time of consumer heterogeneity creates differences between a producer's ability to extract consumer surplus with preventives and treatments, potentially distorting R&D decisions. If consumers vary only in disease risk, revenue...

While many developing-country policymakers see heavy fertilizer subsidies as critical to raising agricultural productivity, most economists see them as distortionary, regressive, environmentally unsound, and argue that they result in politicized, inefficient distribution of fertilizer supply. We...

Dynamically and statically optimal Pigouvian subsidies on durables will differ in a growing economy. For durables with positive externalities, such as sanitation, statically optimal subsidies will typically grow. However, in a dynamic game, governments can most cheaply induce optimal purchasing...

Advocates of teacher incentive programs argue that they can strengthen weak incentives, while opponents argue they lead to teaching to the test.' We find evidence that existing teacher incentives in Kenya are indeed weak, with teachers absent 20% of the time. We then report on a randomized...

In many societies, social norms create common property rights in natural resources, limiting incentives for private investment. This paper uses a randomized evaluation in Kenya to measure the health impacts of investments to improve source water quality through spring protection, estimate the...

It is often argued that low tax rates on owner-occupied housing divert investment from equipment. This paper demonstrates that if people are heterogeneous in their propensity to save, and if there are constraints on borrowing, favorable tax treatment of owner-occupied housing up to a certain...

A randomized evaluation suggests that a program which provided official textbooks to randomly selected rural Kenyan primary schools did not increase test scores for the average student. In contrast, the previous literature suggests that textbook provision has a large impact on test scores....

We construct and calibrate a model of the world economy in which countries' opportunities to develop depend on their trade with advanced economies. Trade opportunities in turn depend on the relative population of the advanced and developing world. As developing countries become advanced, they...

We prove that, for general demand and cost conditions and market structures, the fraction of first-best surplus that a monopolist is unable to extract in a market provides a tight upper bound on the relative distortions arising from firms' equilibrium decisions at all margins (entry and...