We use detailed data from Indonesian cities to study how variation in density within urban areas affects social capital. For identification, we instrument density with soil characteristics, and control for community averages of observed characteristics. Under plausible assumptions, these...

Collective action is a dynamic process where individuals in a group assess over time the benefits and costs of participating toward the success of a collective goal. Early participation improves the expectation of success and thus stimulates the subsequent participation of other individuals who...

Can ideas mobilize people into collective action? We provide a positive answer to this question by studying how exposure to the Communist ideology shaped an individual's choice to join the Chinese Communist Party (CCP) during the party's formative stage. The individuals we focus on are cadets at...

We study a standard collective action problem in which successful achievement of a group interest requires costly participation by some fraction of its members. How should we model the internal organization of these groups when there is asymmetric information about the preferences of their...

This paper provides the first quantitative economic models of pharmacy benefit management regulation. The price-theoretic models allow for various market frictions and imperfections including market power, coordination costs, tax distortions, and incomplete innovation incentives. A rigorous...

The extent of voluntary cooperation in the presence of externalities is shown as an equilibrium outcome in the supply and demand framework. The analysis uses familiar ingredients to provide a new way of understanding the results of the extensive literature beginning with Buchanan, Coase, Ostrom,...

In theory, equilibrium profits for drug patent holders would not involve significant restraints on production and patient utilization if the market had a mechanism for two-part pricing (Oi 1971) or quantity commitments (Murphy, Snyder, and Topel 2014). In fact, patent expiration has little...

Proposed "delinking" legislation would prohibit Pharmacy Benefit Managers (PBMs) from being remunerated based on the rebates and discounts they negotiate for drug insurance plans serving Medicare beneficiaries. This policy would significantly change drug pricing and utilization and shift...

We study the volunteer's dilemma in environments with heterogeneous preferences and private information. We characterize the efficiency properties of equilibrium, which is a departure from all the previous literature that focuses only on the probability of group success. While the probability of...

We study the impact of mandatory calorie posting on consumers' purchase decisions, using detailed data from Starbucks. We find that average calories per transaction falls by 6%. The effect is almost entirely related to changes in consumers' food choices--there is almost no change in purchases of...