I examine markets for flexible commitment devices populated by agents who value both commitment and ‡exibility, and whose preferences exhibit varying degrees of time inconsistency. I show that, if the agents’ time inconsistency is observable, then both a profit-maximizing monopolist and a welfare-maximizing planner help each agent commit to the efficient level of ‡exibility. If instead the agents’ time inconsistency is unobservable, the monopolist and the planner face a screening problem. I find that, to screen a more time-inconsistent from a less time-inconsistent agent, the monopolist and (possibly) the planner inefficiently curtail the ‡exibility of the device tailored to the first agent, and include unused options in the device tailored to the second agent. My results have important policy implications for designing special savings devices, that use tax incentives to help

Persuaders often face the task of changing their listeners’ world-view, which may involve conveying evidence that disconfirms that view. It has been shown, however, that people are often reluctant to change their worldviews. These aspects of persuasion cannot be captured in the standard Bayesian framework. The paper identifies the constraints, opportunities, and trade-offs of persuading people to change worldview. It finds necessary and sufficient conditions under which it is optimal for persuaders to do so. It also shows when and how they conceal disconfirming evidence and take advantage of their listener’s existing worldview. (JEL D82, D83, D91)

Modeling intergenerational altruism is crucial to evaluate the long‐term consequences of current decisions, and requires a set of principles guiding such altruism. We axiomatically develop a theory of pure, direct altruism: Altruism is pure if it concerns the total utility (rather than the mere consumption utility) of future generations, and direct if it directly incorporates the utility of all future generations. Our axioms deliver a new class of altruistic, forward‐looking preferences, whose weight put on the consumption of a future generation generally depends on the consumption of other generations. The only preferences lacking this dependence correspond to the quasi‐hyperbolic discounting model, which our theory characterizes. Our approach provides a framework to analyze welfare in the presence of altruistic preferences and addresses technical challenges stemming from the interdependent nature of such preferences.

Many e-commerce platforms use buyers’ personal data to intermediate their transactions with sellers. How much value do such intermediaries derive from the data record of each single individual? We characterize this value and find that one of its key components is a novel externality between records, which arises when the intermediary pools some records to withhold the information they contain. Our analysis has several implications about compensating individuals for the use of their data, guiding companies’ investments in data acquisition, and more broadly studying the demand side of data markets. Our methods combine modern information design with classic duality theory and apply to a large class of principal-agent problems.

We study learning via shared news. Each period agents receive the same quantity and quality of firsthand information and can share it with friends. Some friends (possibly few) share selectively, generating heterogeneous news diets across agents. Agents are aware of selective sharing and update beliefs by Bayes’s rule. Contrary to standard learning results, we show that beliefs can diverge in this environment, leading to polarization. This requires that (i) agents hold misperceptions (even minor) about friends’ sharing and (ii) information quality is sufficiently low. Polarization can worsen when agents’ friend networks expand. When the quantity of firsthand information becomes large, agents can hold opposite extreme beliefs, resulting in severe polarization. We find that news aggregators can curb polarization caused by news sharing. Our results hold without media bias or fake news, so eliminating these is not sufficient to reduce polarization. When fake news is included, it can lead to polarization but only through misperceived selective sharing. We apply our theory to shed light on the polarization of public opinion about climate change in the United States.