Adaptation and the Mortality Effects of Temperature Across U.S. Climate Regions.

We estimate how the mortality effects of temperature vary across U.S. climate regions to assess local and national damages from projected climate change. Using 22 years of Medicare data, we find that both cold and hot days increase mortality. However, hot days are less deadly in warm places while cold days are less deadly in cool places. Incorporating this heterogeneity into end-of-century climate change assessments reverses the conventional wisdom on climate damage incidence: cold places bear more, not less, of the mortality burden. Allowing places to adapt to their future climate substantially reduces the estimated mortality effects of climate change.

The Mortality and Medical Costs of Air Pollution: Evidence from Changes in Wind Direction.

We estimate the causal effects of acute fine particulate matter exposure on mortality, health care use, and medical costs among the US elderly using Medicare data. We instrument for air pollution using changes in local wind direction and develop a new approach that uses machine learning to estimate the life-years lost due to pollution exposure. Finally, we characterize treatment effect heterogeneity using both life expectancy and generic machine learning inference. Both approaches find that mortality effects are concentrated in about 25 percent of the elderly population.

DO CONSUMER PRICE SUBSIDIES REALLY IMPROVE NUTRITION?

Many developing countries use food-price subsidies or controls to improve nutrition. However, subsidizing goods on which households spend a high proportion of their budget can create large wealth effects. Consumers may then substitute towards foods with higher non-nutritional attributes (e.g., taste), but lower nutritional content per unit of currency, weakening or perhaps even reversing the subsidy's intended impact. We analyze data from a randomized program of large price subsidies for poor households in two provinces of China and find no evidence that the subsidies improved nutrition. In fact, it may have had a negative impact for some households. (JEL I38; O12; Q18).

The impact of food price increases on caloric intake in China.

World food prices have increased dramatically in recent years. We use panel data from 2006 to examine the impact of these increases on the consumption and nutrition of poor households in two Chinese provinces. We find that households in Hunan suffered no nutrition declines. Households in Gansu experienced a small decline in calories, though the decline is on par with usual seasonal effects. The overall nutritional impact of the world price increase was small because households were able to substitute to cheaper foods and because the domestic prices of staple foods remained low due to government intervention in grain markets.

Giffen Behavior and Subsistence Consumption.

This paper provides the first real-world evidence of Giffen behavior, i.e., upward sloping demand. Subsidizing the prices of dietary staples for extremely poor households in two provinces of China, we find strong evidence of Giffen behavior for rice in Hunan, and weaker evidence for wheat in Gansu. The data provide new insight into the consumption behavior of the poor, who act as though maximizing utility subject to subsistence concerns. We find that their elasticity of demand depends significantly, and nonlinearly, on the severity of their poverty. Understanding this heterogeneity is important for the effective design of welfare programs for the poor. (JEL D12, O12).

Insurer-provider integration, credible commitment, and managed-care backlash.

People distrust managed care organizations (MCOs) more than traditional health plans. This phenomenon has become known as "managed-care backlash." Using a model of the interaction between insurers, physicians, and patients, this paper identifies two possible motivations for MCO backlash. The first, which comes from traditional health plans' superior ability to credibly commit to providing better than least-cost care, is efficiency promoting. The second, which arises when patients are able to obtain higher-benefit treatments through reneging on their initial insurance contracts through "doctor shopping," may reduce efficiency.

Pricing health benefits: a cost-minimization approach.

We study the role of health benefits in an employer's compensation strategy, given the overall goal of minimizing total compensation cost (wages plus health-insurance cost). When employees' health status is private information, the employer's basic benefit package consists of a base wage and a moderate health plan, with a generous plan available for an additional charge. We show that in setting the charge for the generous plan, a cost-minimizing employer should act as a monopolist who sells "health plan upgrades" to its workers, and we discuss ways tax policy can encourage efficiency under cost-minimization and alternative pricing rules.