Discounts and Deadlines in Consumer Search

We present a new equilibrium search model where consumers initially search among discount opportunities, but are willing to pay more as a deadline approaches, eventually turning to full-price sellers. The model predicts equilibrium price dispersion and rationalizes discount and full-price sellers coexisting without relying on ex ante heterogeneity. We apply the model to online retail sales via auctions and posted prices, where failed attempts to purchase reveal consumers' reservation prices. We find robust evidence supporting the theory. We quantify dynamic search frictions arising from deadlines and show how, with deadline-constrained buyers, seemingly neutral platform fee increases can cause large market shifts. (JEL D11, D44, D83, L81)

An Equilibrium Model of the African HIV/AIDS Epidemic

Twelve percent of the Malawian population is HIV infected. Eighteen percent of sexual encounters are casual. A condom is used a third of the time. To analyze the Malawian epidemic, a choice‐theoretic general equilibrium search model is constructed. In the developed framework, people select between different sexual practices while knowing the inherent risk. The calibrated model is used to study several policy interventions, namely, ART, circumcision, better condoms, and the treatment of other STDs. The efficacy of public policy depends upon the induced behavioral changes and equilibrium effects. The framework complements the insights from epidemiological studies and small‐scale field experiments.

The Role of Marriage in Fighting HIV: A Quantitative Illustration for Malawi

How might policies that promote marriage and/or dissuade divorce help in the fight against HIV/AIDS? This question is addressed employing a choice-theoretic general equilibrium search model, using Malawi as a case study. In the framework developed, individuals can choose between married and single life. A single person can select among abstinence and sex with or without a condom. The results suggest that marriage-friendly policies can help to abate HIV/AIDS. The policy predictions that obtain from general equilibrium analysis are compared with those that arise from simulated synthetic field experiments and epidemiological studies.

OPTIMAL UNEMPLOYMENT INSURANCE: HOW IMPORTANT IS THE DEMAND SIDE?

I develop and calibrate an equilibrium search model with endogenous savings and search intensity. The wage is endogenized using Nash bargaining and the number of vacancies is tied down by a free entry condition. This allows me to conduct a counterfactual analysis of the optimal unemployment insurance (UI) level. The provision of UI is motivated by the worker's inability to perfectly insure against income shocks, but at the same time UI introduces distortions into workers' search intensity decisions and firm vacancy creation. I find that equilibrium effects are important. When the UI level is raised 25%, they constitute around one-third of the increase in total unemployment. However, even with limited savings by workers, optimal UI is close to zero. It is further shown that ignoring the possibility of self-insurance greatly affects the optimal UI level.