Xavier Sala-i-Martin and Maxim Pinkovskiy estimate income distributions, poverty rates, and other measures of well-being for African countries for the period 1970-2006. They show that African poverty is falling, and that the African poverty reduction is remarkably general. This poverty reduction cannot be explained by a large country, or even by a single set of countries possessing some beneficial geographical or historical characteristic.

In June 2009, the World Health Organization declared that novel influenza A (nH1N1) had reached pandemic status worldwide, and the response by the public and by the public health community -- in terms of canceling public gatherings, advising hand washing, and the like -- was immediate and widespread. However, the forecast models used by public health officials in making many policy decisions, including those regarding vaccinations, tend to ignore such avoidance responses. With a model that explicitly accounts for such avoidance behavior and data from the U.S. summer and the Australian winter flu epidemics of 2009, Byung-Kwang Yoo, Megumi Kasajima, and Jay Bhattacharya forecast the course of the epidemic in the United States in 2010. They conclude that accounting for avoidance responses results in more accurate forecasts and that using models that incorporate such avoidance responses increases the estimated number of lives saved, and the number of infections avoided, from an early vaccination campaign.

How does government spending affect the aggregate economy? Chris Nekarda and Valerie Ramey use Input-Output Tables and NBER's Manufacturing Industry Database to investigate the industry-level effects of government purchases. They find that increases in government purchases raise output and hours, while lowering real product wages and productivity. Markups do not change as a result of increases in government demand.