Knowledge that Transforms

We develop a theory of fertility, distinguishing its intensive margin from its extensive margin. The deep parameters are identified using facts from the 1990 US Census: (i) fertility of mothers decreases with education; (ii) childlessness exhibits a U-shaped relationship with education; (iii) the relationship between marriage rates and education is hump-shaped for women and increasing for men. We estimate that 2.5 percent of women were childless because of poverty and 8.1 percent because of high opportunity cost of childrearing. Over time, historical trends in total factor productivity and in education led to a U-shaped response in childlessness rates while fertility of mothers decreased.

Claims that the VAT facilitates tax enforcement by generating paper trails on transactions between firms contributed to widespread VAT adoption worldwide, but there is surprisingly little evidence. This paper analyzes the role of third-party information for VAT enforcement through two randomized experiments among over 400,000 Chilean firms. Announcing additional monitoring has less impact on transactions that are subject to a paper trail, indicating the paper trail's preventive deterrence effect. This leads to strong enforcement spillovers up the VAT chain. These findings confirm that when taking evasion into account, significant differences emerge between otherwise equivalent forms of taxation.

In an ongoing evaluation of post-secondary financial aid, we use random assignment to assess the causal effects of large privately-funded aid awards. Here, we compare the unbiased causal effect estimates from our RCT with two types of non-experimental econometric estimates. The first applies a selection-on-observables assumption in data from an earlier, nonrandomized cohort; the second uses a regression discontinuity design. Selection-on-observables methods generate estimates well below the experimental benchmark. Regression discontinuity estimates are similar to experimental estimates for students near the cutoff, but sensitive to controlling for the running variable, which is unusually coarse.

We derive a dynamic theoretical model of renewable resource extraction. In the social optimum, maximum extraction occurs in the last period only, while in the unique subgame perfect Nash equilibrium, the resource is depleted immediately. The predictions are tested in a field experiment conducted at a recreational fishing pond. The subjects, experienced recreational fishermen, face a dynamic social dilemma, in which they risk depletion of the resource by overfishing. We find strong support for the Nash equilibrium. Fishermen exert as much effort in the last period as in preceding periods, and effort is independent of the stock of fish.

We analyze randomized online survey experiments providing interactive, customized information on US income inequality, the link between top income tax rates and economic growth, and the estate tax. The treatment has large effects on views about inequality but only slightly moves tax and transfer policy preferences. An exception is the estate tax—informing respondents of the small share of decedents who pay it doubles support for it. The small effects for all other policies can be partially explained by respondents' low trust in government and a disconnect between concerns about social issues and the public policies meant to address them.

This paper combines panel data on monthly mortality rates of US states and daily temperature variables for over a century (1900-2004) to explore the regional evolution of the temperature-mortality relationship and documents two key findings. First, the impact of extreme heat on mortality is notably smaller in states that more frequently experience extreme heat. Second, the difference in the heat-mortality relationship between hot and cold states declined over 1900-2004, though it persisted through 2004. Continuing differences in the mortality consequences of hot days suggests that health motivated adaptation to climate change may be slow and costly around the world.

In a recent experimental study of intertemporal risky decision making, Andreoni and Sprenger (2012) find that subjects exhibit a preference for intertemporal diversification, which is inconsistent with discounted expected utility theory. It was claimed that their results are also at odds with models involving probability weighting, such as rank-dependent utility and cumulative prospect theory. Here we demonstrate, however, that rank-dependent probability weighting explains intertemporal diversification if decision makers care about portfolio risk. Moreover, we provide a unified account of all of Andreoni and Sprenger's key findings.

We use data from a housing-assistance experiment to estimate a model of neighborhood choice. The experimental variation effectively randomizes the rents which households face and helps identify a key structural parameter. Access to two randomly selected treatment groups and a control group allows for out-of-sample validation of the model. We simulate the effects of changing the subsidy-use constraints implemented in the actual experiment. We find that restricting subsidies to even lower poverty neighborhoods would substantially reduce take-up and actually increase average exposure to poverty. Furthermore, adding restrictions based on neighborhood racial composition would not change average exposure to either race or poverty.

We develop an infinite horizon macroeconomic model of banking that allows for liquidity mismatch and bank runs. Whether a bank run equilibrium exists depends on bank balance sheets and an endogenous liquidation price for bank assets. While in normal times a bank run equilibrium may not exist, the possibility can arise in recessions. A run leads to a significant contraction in intermediation and aggregate economic activity. Anticipations of a run have harmful effects on the economy even if the run does not occur. We illustrate how the model can shed light on some key aspects of the recent financial crisis.

Sex ratio at birth remains highly skewed in Asian countries due to son preference. In South Korea, however, it has declined to the natural ratio. In this paper, we investigate whether son preference has disappeared in Korea by analyzing parents' time and monetary inputs by the sex of their child. We exploit randomness of the first child's sex to overcome potential bias from endogenous fertility decisions. Our findings show that mothers are more likely to work after having a girl, girls spend twice as much time as boys in housework activities, and parents spend more on private education for boys.