We model happiness as a measurement tool used to rank alternative actions. Evolution favors a happiness function that measures the individual’s success in relative terms. The optimal function is based on a time-varying reference point—or performance benchmark—that is updated...

A sender randomly draws a “prospect” characterized by its profitability to the sender and its relevance to a receiver. The receiver observes only a signal provided by the sender and accepts the prospect if his Bayesian inference about the prospect’s relevance exceeds his opportunity cost....

This paper considers the costs of reducing consumption of a good by making its production illegal and punishing apprehended illegal producers. We use illegal drugs as a prominent example. We show that the more inelastic either demand for or supply of a good is, the greater the increase in social...