Knowledge that Transforms

We provide an example that shows that in the Alesina and Angeletos (2005) model one can obtain multiplicity even if luck plays no role in the economy. Thus, it is not critical that the noise to signal ratio be increasing in taxes, or that desired taxes are increasing in the noise to signal ratio.

The purpose of this note is to analyze properties of the risk lovers' utility function beyond the positive sign of its second order derivative. We show that—contrarily to a priori beliefs—risk lovers are prudent and are willing to accumulate precautionary savings.

One in five Zambian children lives with an HIV/AIDS-infected adult. We estimate the effect that the availability of adult antiretroviral therapy (ART) has on the health of such children. Using a triple difference specification, we find that adult access to ART resulted in increased weight-for-age and decreased incidence of stunting among children younger than 60 months who resided with an infected father or other infected adult in an intact household. Because the increased availability of adult ART in sub-Saharan Africa has multigenerational effects, cost-effectiveness estimates restricted to direct recipients understate the economic benefit of the treatment.

We conducted a national survey of department Chairs to investigate whether departments of economics changed course requirements for bachelors degrees since the Siegfried and Bidani (1992) paper using 1980 data. There have been few changes to course requirements. Most notable are a large increase in the number of departments requiring econometrics and a drop in departments requiring courses such as money, banking and economic history--courses once required in many business schools.

The interplay between religion and the economy has long occupied social scientists. We construct a unique panel of income and Protestant church attendance using 175 Prussian counties, presented in six waves from 1886 to 1911. The data reveal a marked decline in church attendance coinciding with increasing income. The cross-section also shows a negative association between income and church attendance. The associations disappear in panel analyses, including first-differenced models of the 1886 to 1911 change, panel models with county and time fixed effects, and panel Granger-causality tests. The results cast doubt on causal interpretations of the religion-economy nexus in Prussian secularization.

We study risk attitudes, ambiguity attitudes, and time preferences of 661 children and adolescents, aged ten to eighteen years, in an incentivized experiment and relate experimental choices to field behavior. Experimental measures of impatience are found to be significant predictors of health-related field behavior, saving decisions, and conduct at school. In particular, more impatient children and adolescents are more likely to spend money on alcohol and cigarettes, have a higher body mass index, are less likely to save money, and show worse conduct at school. Experimental measures for risk and ambiguity attitudes are only weak predictors of field behavior.

We measure the change in household spending caused by receipt of the economic stimulus payments of 2008, using questions added to the Consumer Expenditure Survey and variation from the randomized timing of disbursement. Households spent 12–30 percent (depending on specification) of their payments on nondurable goods during the three-month period of payment receipt, and a significant amount more on durable goods, primarily vehicles, bringing the total response to 50–90 percent of the payments. The responses are substantial and significant for older, lower-income, and home-owning households. Spending does not vary significantly with the method of disbursement (check versus electronic transfer).

We investigate whether car buyers are myopic about future fuel costs. We estimate the effect of gasoline prices on short-run equilibrium prices of cars of different fuel economies. We then compare the implied changes in willingness-to-pay to the associated changes in expected future gasoline costs for cars of different fuel economies in order to calculate implicit discount rates. Using different assumptions about annual mileage, survival rates, and demand elasticities, we calculate a range of implicit discount rates similar to the range of interest rates paid by car buyers who borrow. We interpret this as showing little evidence of consumer myopia.

Using data from a field experiment in Kenya, we document that providing individuals with simple informal savings technologies can substantially increase investment in preventative health and reduce vulnerability to health shocks. Simply providing a safe place to keep money was sufficient to increase health savings by 66 percent. Adding an earmarking feature was only helpful when funds were put toward emergencies, or for individuals that are frequently taxed by friends and relatives. Group-based savings and credit schemes had very large effects.

We offer a theory of polarization as an optimal response to ambiguity. Suppose individual A's beliefs first-order stochastically dominate individual B's. They observe a common signal. They exhibit polarization if A's posterior dominates her prior and B's prior dominates her posterior. Given agreement on conditional signal likelihoods, we show that polarization is impossible under Bayesian updating or after observing extreme signals. However, we also show that polarization can arise after intermediate signals as ambiguity averse individuals implement their optimal prediction strategies. We explore when this polarization will occur and the logic underlying it.