Larry Samuelson Publications

We consider an economy in which long-lived experts are matched with short-lived clients. Experts choose the type of client with whom they match, unobserved by the market. The interaction outcome depends on both the expert's and the client's type. We study the effects of supplying information about otherwise unobservable outcomes, such as "medical report cards," to help clients identify better experts. Such information can lead to inefficient matches, as experts reject risky clients to build their reputation. Hence, information can reduce welfare. Withholding information can mitigate these perverse incentives at the cost of misallocating experts known to be inept.

We investigate the impact of wealth redistribution on economic growth, building on Kelly's (1956) optimal investment portfolio theory. A growth-optimal policy redistributes wealth from "lucky" overperforming individuals to underperforming ones, minimizing the systematic component of this redistribution in a myopic fashion. That is, the optimal policy minimizes the discrepancy between endowments and outcomes, counterfactually taking outcomes as independent of endowments. The myopia in this result follows from a decoupling argument that allows us to model the planner as independently choosing a growth-maximizing policy and a pattern of wealth circulation.

We offer an approach to cooperation in repeated games of private monitoring in which players construct models of their opponents' behavior by observing the frequencies of play in a record of past plays of the game in which actions but not signals are recorded. Players construct models of their opponent's behavior by grouping the histories in the record into a relatively small number of analogy classes for which they estimate probabilities of cooperation. The incomplete record and the limited number of analogy classes lead to misspecified models that provide the incentives to cooperate. We provide conditions for the existence of equilibria supporting cooperation and equilibria supporting high payoffs for some nontrivial analogy partitions.

We examine the evolutionary selection of attitudes toward aggregate risk in an age structured population. Aggregate shocks perturb the population's consumption possibilities. Consumption is converted to fertility via a technology that exhibits first increasing and then decreasing returns to scale, captured in the simplest case by a fertility threshold. We show that evolution will select preferences that exhibit arbitrarily high aversion to aggregate risks with even very small probabilities of sufficiently low outcomes. These findings complement the familiar result that evolution will select for greater aversion to aggregate than idiosyncratic risks by identifying circumstances under which the difference can be extreme.