Panel and time-series data describing the green-revolution period in India are used to assess the effects of exogenous technical change on the returns to schooling, the effects of schooling on the profitability of technical change, and the effects of technical change and school availability on household schooling investment. The results indicate that the returns to (primary) schooling increased during a period of rapid technical progress, particularly in areas with the highest growth rates. Such increases induced private investment in schooling, net of changes in wealth, wages, and the availability of schools, and school expansion importantly increased levels of schooling.

One of the oldest and most studied questions in development is whether the resource and environmental conditions faced by households in low-income rural areas significantly affect productivity.' The reason for this interest is clear: if productivity is significantly constrained by these factors, then the returns to investment in the form of human capital are likely to be high, and under certain conditions there may be scope for efficiency-improving policies and programs. Given this motivation it may at first seem surprising that most of the existing literature focusing on the health-productivity relationship concentrates on the effects of nutrition. While nutrition is an important contributor to good health, other components of health, especially illness, may also influence worker productivity. Moreover, in contrast to the case of nutrition, over which households have direct control, illness is affected by exposure to pathogens, something over which individual households may have little control. This public aspect of illness makes an examination of the effects of illness on productivity particularly important from a policy perspective. This distinction between the private nature of nutrition and the public nature of illness may at least in part be evident in Tables 1 and 2. These tables present the distribution of illness and calories, respectively, by wealth quartiles in three Asian countries. What is most striking about these tables is the fact that despite clear evidence that calories are importantly associated with wealth in at least two of the countries (Bangladesh and Pakistan) there is little systematic relationship between illness and wealth in any of the countries. For example, in Bangladesh, the top quartile (in terms of wealth) of the population of men and women consumes 6 percent and 8 percent more calories, respectively, than the lowest quartile. By contrast, Bangladeshi males in the upper quartile experience 19-percent more days ill over the same period than do those in the lower quartile; the figures for the women are identical. There are several possible reasons for this pattern. As suggested earlier, one possibility is that households have little control over their exposure to illness. If this is the case, then one might well conclude that the distributional effects of illness are quite limited. A second plausible explanation is that illness is measured or reported differently for better-off households. For example, a better-off individual who is generally healthy may be more readily able to identify when he or she is ill than a poor individual with low caloric intake. Moreover, to the extent that illness is measured as an alternative to work (as is the case for the Pakistani data set), a wealthier individual may be more willing to skip work on a day that he or she is ill. If this latter point is true, then the distributional consequences of illness could be quite important despite what is evident in Table 1.2 In this paper I address these and other related issues using two of the longitudinal data sets from rural Asia from which these tables were derived. In the first section of

In the presence of imperfect information, voluntary certification can provide an important complement to mandatory inspections as a basis for environmental regulation in low income countries. Using data from Mexico's Clean Industry Program, we show that patterns of compliance and certification by sector are consistent with a model in which selection into the voluntary program permits more efficient targeting of regulator effort. As expected given the informational role played by certification in the model, we also find evidence, for a sample of publicly traded firms, of positive stock price deviations linked to the announcement of certification.

Panel and time-series data describing the green-revolution period in India are used to assess the effects of exogenous technical change on the returns to schooling, the effects of schooling on the profitability of technical change, and the effects of technical change and school availability on household schooling investment. The results indicate that the returns to (primary) schooling increased during a period of rapid technical progress, particularly in areas with the highest growth rates. Such increases induced private investment in schooling, net of changes in wealth, wages, and the availability of schools, and school expansion importantly increased levels of schooling.

The increasing body of evidence from high income countries linking pollution to health outcomes (Ken Chay and Michael Greenstone 2003; Janet Currie and Matthew Neidell 2004), has raised concerns about the health impact of adverse air quality in developing countries, where, in general, environmental regulation is less stringent and health monitoring and treatment are less accessible. These concerns have, in turn, encouraged consideration of the effectiveness of alternative mechanisms for improving air quality while limiting the adverse impact on economic growth. However, the analysis of both the effects of pollution on health and the effectiveness of pollution abatement policies faces particular empirical challenges in low- and middle-income contexts, given the scarcity of reliable measures of pollution concentrations. The primary source of good quality data on air quality, ground monitoring, tends to be limited to larger metropolitan areas with monitors placed at sentinel sites that may or may not yield a representative picture of population exposure. This paper calls attention to, and makes use of, newly available procedures for extracting measures of air quality from satellite imagery. In particular, satellite-based measures of aerosol optical depth (AOD) are used to obtain estimates of air quality for the whole Mexican territory at a detailed geographic scale, and these estimates are related to measures of participation in a voluntary certification program at the level of the county. The resulting estimates are then combined with estimates of the relationship between participation in the certification program and infant mortality due to respiratory causes to obtain a rough estimate of the relationship between air quality and infant health in Mexico.

A novel experiment is used to show that the effect of a policy on the level of cooperation is greater when it is chosen democratically by the subjects than when it is exogenously imposed. In contrast to the previous literature, our experimental design allows us to control for selection effects (e.g. those who choose the policy may be affected differently by it). Our finding implies that democratic institutions may affect behavior directly in addition to having effects through the choice of policies. Our findings have implications for the generalizability of the results of randomized policy interventions.