Various forms of substitutability are essential for establishing the existence of equilibria and other useful properties in diverse settings such as matching, auctions, and exchange economies with indivisible goods. We extend earlier models’ definitions of substitutability to settings in which each agent can be both a buyer in some transactions and a seller in others, and show that all these de...

Abstract A 70 years–old man with a history of systemic hypertension and surgically treated bilateral carpal tunnel was referred for dyspnea on exertion few months. At physical examination systolic heart murmur exacerbated by Valsalva maneuver appreciated; no signs failure. EKG low–voltage QRS is shown in Fig.1A. Blood tests showed elevated NT–proBNP (1434 pg/ml). Transthoracic echo (ETT) reveal...

More economists are interested in analyzing situations in which cooperative behavior within a coalition coexists with strategic behavior across the coalitions. The underlying equilibrium is defined as the hybrid solution with a distribution rule (HSDR), which could contribute to these studies to the same extent that Nash equilibrium does to strategic behavior. The paper also defines the stable ...

Vote-trading is common practice in committees and group decision-making. Yet we know very little about its properties. Inspired by the similarity between the logic of sequential rounds of pairwise vote-trading and matching algorithms, we explore three central questions that have parallels in the matching literature: (1) Does a stable allocation of votes always exists? (2) Is it reachable throug...

De Finetti’s Theorem asserts that a sequence of exchangeable variables are conditionally independent, that is, dependence under exchangeability is nothing but conditionally independence. However, de Finetti’s theorem is valid only with a infinite number of random variables, which makes this result unsuitable for application in many economic models. In this paper, we prove that dependence is con...

A population of individuals is divided into groups. Individuals are recurrently randomly matched with individuals from their group to play a generic symmetric 2-player game. Deterministic interand intragroup dynamics are derived from a model of individual imitation within groups and individual migration between groups. Conditions are identified under which subsets (components) of the set of sta...

This paper gives local stability conditions for convergence of the price dynamics in a cobweb model with rationally heterogeneous expectations, generalizing the example of Brock and Hommes (1997). When agents choose between rational, naive, and adaptive beliefs, the steady state may be locally asymptotically stable if the adaptive predictor places enough weight on past prices and is costless. I...