Progress on child mortality requires better curative care, but common policies to improve access risk reducing underuse incompletely or creating overuse. In an RCT of 1,768 children in Mali we analyze how subsidized care and community health worker (CHW) visits affect the targeting of acute care, using nine weeks of daily health data to measure demand conditional on need for care per WHO standards. Parents are five times more likely to seek care when medically indicated. Subsidies increase utilization by over 250%, significantly reducing underuse with moderate effects on overuse. CHW do not improve efficient health care utilization on average.

Incentivized experiments are often used to identify the time preferences of households in developing countries. We argue theoretically and empirically that experimental measures may not identify preference parameters, but are a useful tool for understanding financial shocks and constraints. Using data from an experiment in Mali, we find that subject responses vary with savings and financial shocks, meaning they provide information about credit constraints and can be used to test models of risk sharing.

We introduce a new measure of how close a set of choices is to satisfying the observable implications of rationality and apply it to a large, balanced panel of household level consumption data. This new measure, the minimum cost index, is the minimum cost of breaking all revealed preference cycles found in choices from budget sets. Unlike existing measures of rationality, it responds to both the number and severity of revealed preference violations.