Publications by Author: Michael Kremer

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 from treatments—sold after the disease is contracted, when disease risk is no longer a source of private information—always exceeds revenue from preventives. The revenue ratio can be arbitrarily high for sufficiently skewed distributions of disease risk. Under some circumstances, heterogeneity in harm from a disease, learned after a disease is contracted, can lead revenue from a treatment to exceed revenue from a preventative. Calibrations suggest that skewness in the US distribution of HIV risk would lead firms to earn only half the revenue from a vaccine as from a drug. Empirical tests are consistent with the predictions of the model that vaccines are less likely to be developed for diseases with substantial disease-risk heterogeneity.

The 2003 United Nations Global Report on Human Settlements estimates that 924 million people, or 31.6% of the world’s urban population, lived in slums in 2001. Although forecasts are difficult, it is generally agreed that this number could greatly increase in coming years in the absence of strong policy interventions. These trends underscore the importance of slum upgrading strategies for addressing the growing problems of urban poverty.

Upgrading projects focus on providing basic services to improve the well-being of low income communities, including a range of infrastructure interventions frequently undertaken in conjunction with social interventions, such as the regularization of areas with insecure tenure. Other infrastructure improvements include water, sanitation, waste collection, housing, access roads, footpaths, storm drainage, lighting, public telephones, schools, health posts and community centers. Social improvements can include better provision of health and education services, day care, training, and social protection programs. With the projected increases in slum population, the demand for urban upgrading interventions is expected to grow.

Intestinal helminths – including hookworm, roundworm, whipworm, and schistosomiasis – infect more than one–quarter of the world's population. Studies in which medical treatment is randomized at the individual level potentially doubly underestimate the benefits of treatment, missing externality benefits to the comparison group from reduced disease transmission, and therefore also underestimating benefits for the treatment group. We evaluate a Kenyan project in which school–based mass treatment with deworming drugs was randomly phased into schools, rather than to individuals, allowing estimation of overall program effects. The program reduced school absenteeism in treatment schools by one–quarter, and was cheaper than alternative ways of boosting school participation. Deworming substantially improved health and school participation among untreated children in both treatment schools and neighboring schools, and these externalities are large enough to justify fully subsidizing treatment. Yet we do not find evidence that deworming improved academic test scores.

Some argue that sovereign debt incurred without the consent of the people and not for their benefit, such as that of apartheid South Africa, should be considered odious and not transferable to successor governments. We argue that an institution that truthfully announced whether regimes are odious could create an equilibrium in which successor governments suffer no reputational loss from failure to repay odious debt and hence creditors curtail odious lending. Equilibria with odious lending could be eliminated by amending creditor country laws to prevent seizure of assets for failure to repay odious debt and restricting foreign assistance to countries not repaying odious debt. Shutting down the borrowing capacity of illegitimate regimes can be viewed as a form of economic sanction and has two advantages over most sanctions: it helps rather than hurts the population, and it does not create incentives for evasion by third parties. However, an institution empowered to assess regimes might falsely term debt odious if it favored debtors, and if creditors anticipate this, they would not make loans to legitimate governments. An institution empowered only to declare future lending to a particular government odious would have greater incentives to judge truthfully. A similar approach could be used to reduce moral hazard associated with World Bank and IMF loans.

Colombia's PACES program provided over 125,000 pupils from poor neighborhoods with vouchers that covered approximately half the cost of private secondary school. Vouchers were renewable annually based on satisfactory performance. Since many vouchers were allocated by lottery, we use differences in outcomes between lottery winners and losers to assess program effects. Three years into the program, lottery winners were 15 percentage points more likely to have attended private school, had completed .1 more years of schooling, and were about 10 percentage points more likely to have finished 8th grade, primarily because they were less likely to repeat grades. The program did not significantly affect dropout rates. Lottery winners scored .2 standard deviations higher on standardized tests. There is some evidence that winners worked less than losers and were less likely to marry or cohabit as teenagers. On average, lottery winners increased their educational expenditure by about 70% of the value of the voucher. Since winners also worked less, they devoted more total resources to education. Compared to an equivalent expansion of the public education system, the voucher program increased annual government educational expenditure by about $24 per winner. But the costs to the government and to participants were probably much less than the increase in winners' earnings due to greater educational attainment.

According to WHO, while 50 percent of global health research and development (R&D) in 1992 was undertaken by private industry, less than 5 percent of that was spent on diseases specific to less developed countries (LDCs).1,2 Despite this, private industry has produced major drug discoveries and developments for serious LDC disease threats, including malaria, TB, hepatitis B, river blindness, meningitis, leprosy, sleeping sickness and trachoma. Moreover, the development of globally–applicable drugs and vaccines has led to important advances in public health in developing countries. At the same time, the simple fact is that every company in the biopharmaceutical industry has a limited number of research and development programmes in their portfolio. These projects are regularly reviewed against each other using a variety of analytical tools. Fundamentally the process tends to favour those projects with a higher probability of success and which, if successful, would serve markets with a larger value. As a result, there is underinvestment in and comparative neglect of some diseases concentrated in LDCs, such as tuberculosis and malaria, despite their high global disease burden. It is therefore generally agreed that new mechanisms and incentives are needed to encourage industrial R&D in such diseases. In this paper, we summarize some recent thinking about ways to stimulate industrial R&D for neglected infectious diseases, and we argue that enlarging the value of the market for drugs and vaccines for these diseases is a critical step toward stimulating R&D.

This paper reports some preliminary cost–effectiveness estimates for vaccine purchase commitments. Besides assessing the merit of a purchase program, this analysis can be used to examine the cost–effectiveness of purchasing vaccines with different characteristics, and thus to help establish eligibility requirements and identify prices at which vaccines with different characteristics might be purchased.

This paper compares retrospective and prospective analyses of the effect of flip charts on test scores in rural Kenyan schools. Retrospective estimates that focus on subjects for which flip charts are used suggest that flip charts raise test scores by up to 20 percent of a standard deviation. Controlling for other educational inputs does not reduce this estimate. In contrast, prospective estimators based on a study of 178 schools, half of which were randomly selected to receive charts, provide no evidence that flip charts increase test scores. One interpretation is that the retrospective results were subject to omitted variable bias despite the inclusion of control variables. If the direction of omitted variable bias were similar in other retrospective analyses of educational inputs in developing countries, the effects of inputs may be even more modest than retrospective studies suggest. Bias appears to be reduced by a differences–in–differences estimator that examines the impact of flip charts on the relative performance of students in flip chart and other subjects across schools with and without flip charts, but it is not clear that this approach is applicable more generally.

Today, the United States government spurs research mainly through direct funding and the granting of patents. Both methods are vitally important, but each causes serious problems–and each has proved inadequate in spurring the research needed to develop effective vaccines against HIV, tuberculosis and malaria.

This paper examines the effect of reduced transaction costs in the international trading of assets on the ability of governments to issue debt. We examine a model in which governments care about the welfare of their citizens, and thus are more inclined to default if a large proportion of their debt is held by foreigners. Reductions in transaction costs make it easier for domestic citizens to share risk by selling debt to foreigners. This may increase tendencies for governments to default, and thus raise their cost of credit and reduce welfare. We find that even in the absence of transaction costs, home bias in placement of government debt may persist, because in the presence of default risk the return on government debt is correlated with the tax burden required to pay the debt. Asset inequality may reduce this home bias, and by increasing foreign ownership, increase incentives for default. Finally, if foreign creditors are less risk averse than domestic creditors, there may be one equilibrium in which domestic creditors hold the asset and default risk is low, and another in which foreign creditors hold the asset and default risk is high.

Developing countries with highly unequal income distributions, such as Brazil or South Africa, face an uphill battle in reducing inequality. Educated workers in these countries have a much lower birthrate than uneducated workers. Assuming children of educated workers are more likely to become educated, this tends to increase the proportion of unskilled workers, reducing their wages, and thus their opportunity cost of having children, creating a vicious cycle. A model incorporating this effect generates multiple steady–state levels of inequality, suggesting that in some circumstances, temporarily increasing access to educational opportunities could permanently reduce inequality. Empirical evidence suggests that the fertility differential between the educated and uneducated is greater in less equal countries, consistent with the model.

In response to the widespread consensus on the importance of social capital, and to concerns about the scarcity of institutions giving voice to disadvantaged groups, some donors have begun programs designed to strengthen indigenous community organizations. We use a prospective, randomized evaluation to examine a development program explicitly targeted at building social capital among rural women's groups in western Kenya. The program increased turnover among group members. It increased entry into group membership and leadership by younger, more educated women, by women employed in the formal sector, and by men. The analysis suggests that providing development assistance to indigenous community organizations of the disadvantaged may change the very characteristics of these organizations that made them attractive to outside funders.