理论论文

We show that the formalization of representativeness (Kahneman and Tversky, 1972, Cognitive Psychology, 3, 430–454) developed by Gennaioli and Shleifer (2010, The Quarterly Journal of Economics, 125, 1399–1433) features an intrinsic connection between uncertainty and overreaction. In the time series domain, we develop this connection in a smooth version of diagnostic expectations (DE), where overreaction varies smoothly with uncertainty. Intuitively, under smoothness, lower uncertainty leaves less room for representativeness to distort beliefs. Smooth DE provides a joint, parsimonious micro-foundation for key features of survey data: overreaction to news, stronger overreaction at longer horizons, overconfidence in subjective uncertainty, and a new stylized fact documented here—overreaction intensifies with higher uncertainty. An analytical Real Business Cycle model with Smooth DE accounts for survey overreaction and overconfidence, as well as three salient business cycle properties: asymmetry, countercyclical macro volatility, and countercyclical micro volatility.

Abstract We model a fishery with potential congestion, in which firms obtain public and private signals about the location of the densest fish stock. We analytically determine the regions of parameter space where greater precision of public and/or private information increases welfare, and we examine the effects of two types of information sharing. Using high-resolution data from the world’s largest fishery, we estimate the structural model. Point estimates imply that more precise private information raises welfare, whereas more precise public information has a negligible effect on welfare. Moreover, welfare is much more sensitive to changes in the precision of private information than to changes in the precision of public information. This difference reflects the fact that public information increases congestion more than private information does. We also find empirically that a small amount of information sharing can reduce welfare, whereas more extensive information sharing raises welfare, as do information clubs.

Abstract We introduce markup equilibrium—an extension of Walrasian equilibrium in which consumers pay a fixed percentage markup over producer prices. In quasilinear markets, markup equilibria exist despite nonconvexities. They are resource-feasible and envy-free, incur no budget deficit, and require little more communication and computation than ordinary Walrasian equilibrium. The associated markup mechanism is asymptotically incentive-compatible. We also introduce a Bound-Form First Welfare Theorem, which states that for any feasible allocation, the welfare loss compared to the first-best is bounded, using any price vector, by the sum of the resulting (i) budget surplus and (ii) rationing losses suffered by the participants. Using producer prices, this bound implies that any markup equilibrium with a small markup and few unallocated goods is nearly efficient.