Jessica Cohen

Who they are

Biography beyond the cited work is not recorded, by rule. The paper's record lists Cohen at UCLA and the National Bureau of Economic Research, which is the affiliation at the time of the working paper and may not be current.

She is an economist working on health, and the documented footprint used for this page is two papers written with Pascaline Dupas, the 2010 experiment on bed-net prices and a 2015 study, with Schaner, of subsidies for antimalarial drugs.

Key papers

Cohen, J., & Dupas, P. (2010). "Free Distribution or Cost-Sharing? Evidence from a Randomized Malaria Prevention Experiment." Quarterly Journal of Economics, 125(1), 1-45. First author. Abstract read.

Cohen, J., Dupas, P., & Schaner, S. (2015). "Price Subsidies, Diagnostic Tests, and Targeting of Malaria Treatment: Evidence from a Randomized Controlled Trial." American Economic Review, 105(2), 609-645. First author. Abstract read.

Key ideas

The 2010 paper tests a belief. It is widely held that charging a subsidised, positive price for a health product is necessary to avoid wasting resources on people who will not use it or do not need it. Cohen and Dupas ran a field experiment in Kenya in which they randomised the price at which pregnant women could buy long-lasting anti-malarial insecticide-treated nets at prenatal clinics.

They report three results. First, no evidence that cost-sharing reduces wastage: women who received free nets were not less likely to use them than those who paid subsidised positive prices. Second, no evidence that cost-sharing selects women who need the net more: those who paid higher prices appeared no sicker, in terms of measured anaemia, than the prenatal clients in the control group. Third, cost-sharing considerably dampened demand, with uptake dropping by 75 per cent when the price rose from nothing to $0.75, the price at which nets were then sold to pregnant women in Kenya.

They combined these estimates in a cost-effectiveness analysis of net prices on infant mortality that includes both the private and the social returns to using a net. Given the large positive externality of widespread use, their conclusion is that free distribution to pregnant women is both more effective and more cost-effective than cost-sharing.

For readers interested in pricing psychology, the paper is the field counterpart to the chocolate experiments. It does not show that zero is special against one cent, since it sets nothing against a single positive price, and so it cannot separate the zero price effect from ordinary price sensitivity. What it shows is how steeply demand can fall at the bottom of the scale when the product matters, and that the usual argument for a price, that it improves use and targeting, was not supported in that setting.

The 2015 paper, with Schaner, qualifies the lesson in an important way. It studied antimalarials sold over the counter at retail drug outlets in Kenya and found that a very high subsidy dramatically increases access, but nearly one half of subsidised pills go to patients without malaria. The authors then studied two ways to better target subsidised drugs, reducing the subsidy level and introducing rapid malaria tests over the counter. A price that was a poor filter for bed nets can still have a role where a product can be wasted or misused.

The two papers therefore do not say that free is always right. They say that the case for a price has to be argued from what the price does, in a setting, for a product, and that the argument cannot rest on a belief about human nature.

This page was written from abstracts. The experiments' designs, sample sizes and tables were not read, so none are reported here.

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