Is Kreps-Porteus utility distinguishable from intertemporal expected utility?

Summary In a Lucas (1978) model, with a Kreps-Porteus (1978) nonexpected utility, the following property of equilibrium holds generically in the space of finite-state, Markov output growth rate processes: equilibrium price of equity is distinct from that implied by any intertemporally additive expected utility satisfying specified regularity conditions. In that sense the more general utility functions are observationally distinguishable from the standard expected utility specification.I would like to thank Larry G. Epstein for posing to me the problem studied in this paper and for many suggestions and comments. I am also grateful to Darrell Duffie for helpful suggestions. I am responsible for errors. This papers is part of my Ph.D. thesis at University of Toronto.     

Market clearing, utility functions, and securities prices

Summary. We prove the existence of equilibrium in a continuous-time finance model; our results include the case of dynamically incomplete markets as well as dynamically complete markets. In addition, we derive explicitly the stochastic process describing securities prices. The price process depends on the risk-aversion characteristics of the utility function, as well as on the presence of additional sources of wealth (including endowments and other securities). With a single stock, zero endowment in the terminal period, and Constant Relative Risk Aversion (CRRA) utility, the price process is geometric Brownian motion; in essentially any other situation, the price process is not a geometric Brownian motion.JEL Classification Numbers: D52.This paper is part of my Dissertation (UC Berkeley). I am very grateful to my advisor Professor Robert M. Anderson. I also would like to thank Steve Evans, Roger Purves, Jacob Sagi, Chris Shannon and the participants of the 2002 NBER General Equilibrium Conference at the University of Minnesota (Minneapolis) for very helpful discussions and comments. This work was supported by Grant SES-9710424 from the National Science Foundation.     

Fertility,human capital and the wealth of families

Summary An overlapping generations model with parental altruism is examined. The existence of the optimal value function in a model with an endogenous discount rate is proven. Two development regimes are produced: a high fertility, low income and no growth steady state, and a perpetual growth equilibrium with low fertility and rising income.This paper is adapted from my dissertation. I would like to thank the members of my dissertation committee for helpful comments and suggestions, Messrs, Gary S. Becker, Robert E. Lucas, Jr., Kevin M. Murphy and Sherwin Rosen. I'd like to thank Brooks Pierce, Paul Romer, Ken Judd, Beth Ingram, Ed Prescott and Fernando Alvarez. I also thank the workshop participants of the University of Chicago, University of Pennsylvania, University of Toronto, University of Rochester, University of Washington, Penn State University, University at Buffalo, SUNY, Columbia University and University of Iowa.     

Stability,sequential rationality,and subgame consistency

In this paper we analyze dynamic strategic behavior by means of the idea of "stability." We develop a solution concept of "sequentially stable equilibrium (SSE)" that satisfies subgame consistency. All SSEs are characterized by the largest stable set that yields exactly all the backward induction outcomes. We also provide a refinement of the SSE. We compare the SSE and its refinement with some existing solution concepts in the literature We are grateful to the editor and two anonymous referees for very useful comments and suggestions that led to this revision. We thank Chih Chang, Yi-Chun Chen, Chenying Huang, Huiwen Koo, Man-Chung Ng, Shyh-fang Ueng, and Chun-Hsien Yeh for helpful comments and discussions. We also thank participants in seminars at Academia Sinica, National Dong Hwa University, and the Third Pan-Pacific Game Theory Conference. Financial support from the Social Sciences and Humanities Research Council of Canada (SSHRC), the National Science Council of Taiwan, and the Economic and Social Research Council of the UK is gratefully acknowledged. The usual disclaimer applies.     

Decentralizing lottery allocations in markets with indivisible commodities

Summary In economies with indivisible commodities, consumers tend to prefer lotteries in commodities. A potential mechanism for satisying these preferences is unrestricted purchasing and selling of lotteries in decentralized markets, as suggested in Prescott and Townsend [Int. Econ. Rev.25, 1–20]. However, this paper shows in several examples that such lottery equilibria do not always exist for economies with finitely many consumers. Other conditions are needed. In the examples, equilibrium and the associated welfare gains are realized if consumptions are bounded or if lotteries are based upon a common sunspot device as defined by Shell [mimeo, 1977] and Cass and Shell [J. Pol. Econ.91, 193–227]. The paper shows that any lottery equilibrium is either a Walrasian equilibrium or a sunspot equilibrium, but there are Walrasian and sunspot equilibria that are not lottery equilibria.This paper is based on Chapter 3 of my doctoral dissertation, written while I was a student at Cornell University. I thank Larry Blume, Yue Yun Chen, David Easley, Aditya Goenka, John Marshall, Bruce Smith, John Wooders and an anonymous referee. I am particularly grateful to Karl Shell and Cheng-Zhong Qin. I thank the Academic Senate at UCSB for financial support.     

Communication in financial markets with several informed traders

This paper investigates the incentives for informed traders in financial markets to reveal their information truthfully to the public. In the model, a subset of traders receive noisy signals about the value of a risky asset. The signals are composed of a directional component (“high” vs. “low”) as well as a precision component that represents the quality of the directional component. Between trading periods, the informed agents make public announcements to the uninformed traders. With a sufficiently large number of informed traders, an equilibrium exists in which the directional components are credibly revealed, but not the precision components. Even though the informed traders retain some of their rivate information, the post-communication estimate of the asset value converges in probability to the full-information estimate as the number of informed traders increases. The paper is based on a chapter of my Ph.D. thesis at the University of Western Ontario and was circulated previously under the title “Public Communication Devices in Financial Markets.” I thank my dissertation committee Arthur Robson, Hari Govindan, and Al Slivinski for their guidance and support. I also thank Murali Agastya, Roland Benabou, Philippe Grégoire, Rick Harbaugh, Mike Peters, an anonymous referee and an associate editor, and seminar participants at various universities and conferences at which this paper was presented.     

A characterization of social choice correspondences that implement the core of simple games

In a coalitional voting game, an alternative is said to be in the core when no majority is willing to replace it with another alternative. A social choice correspondence is a mapping which associates any profile of voters’ preferences with a non-empty subset of the set of alternatives, which is understood as the set of selected outcomes. We characterize the social choice correspondences which always select the core of a simple game for any profile of preferences. This work was completed when B. Tchantcho was Visiting assistant Professor at UTA (University of Texas at Arlington). We acknowledge the support of the Department of Mathematics of UTA. We are most grateful to R. Pongou of Brown University, USA for his help and advice. We sincerely thank N.G Andjiga for his helpful comments and we are indebted to two anonymous referees for their helpful comments.     

Exactly what happens after the Anscombe–Aumann race?

This paper derives a representation of preferences for a choice theory with vague environments; vague in the sense that the agent does not know the precise lotteries over outcomes conditional on states. Instead, he knows only a possible set of these lotteries for each state. Thus, this paper’s main departure from the standard subjective expected utility model is to relax an assumption about the environment, rather than weakening the axiomatic structure. My model is consistent with the behavior observed in the Ellsberg experiment. It can capture the same type of behavior as the multiple priors models, but can also result in behavior that is different from both the behavior implied by standard subjective expected utility models and the behavior implied by the multiple priors models. This paper is a revised chapter of my Ph.D. dissertation at Cornell University. I am very grateful to David Easley for extensive comments and suggestions. I also thank Larry Blume, Ani Guerdjikova, Edi Karni, Ted O’Donoghue, Maureen O’Hara, Jacob Sagi, seminar participants at the University of Copenhagen, Cornell University, ESEM 2006, Fuqua—Duke University, FUR 2006, Johns Hopkins University, Purdue University, Queen’s University, the University of Warwick, the associate editor, and an anonymous referee for comments and suggestions.     

Petty corruption

This paper analyzes a petty corruption model in which the entrepreneur’s type is drawn from an absolutely continuous probability distribution function F over [0, 1], and perfect Bayesian equilibrium is adopted as the solution concept for a one-stage game. In the one-stage game, if there is more than one bureaucrat, no project is approved with a strictly positive probability. For an infinitely repeated game, I show that the single window policy strictly increases the social benefits in a socially optimal equilibrium. I would like to thank Mukul Majumdar for valuable guidance and encouragement. I am also grateful to Kaushik Basu, Fernando Vega-Redondo, an anonymous referee, seminar participants at the international meeting for public economic theory (PET07) and especially Ani Guerdjikova and Roy Radner for helpful comments. Thanks are due to Hideaki Goto and Eunkyeong Lee for useful conversation.     

Cooperation in the commons

This paper delineates circumstances in which a first-best cooperative solution can be supported as a subgame perfect equilibrium in a dynamic common property renewable resource game. In a game with nonlinear resource stock effects on cost, we characterize a worst perfect equilibrium that supports cooperation for the widest range of parameter values for the discount rate, resource growth rate, harvest price, and the number of resource exploiters. The strategy profile that we propose is consistent with human behavior observed in experiments and common property resource case studies.We thank seminar participants at the University of Minnesota, the Heartland Environmental and Resource Economics Conference at Iowa State University, Keio University, and two anonymous referees for helpful comments.     

On multiple equilibria and the rational expectations hypothesis

Summary This paper analyzes through a simple two-period model the fact that, if some agents hold inside money intertemporally, the second-period normalization matters. Thus, there are several equilibria of the second-period economy, indexed by the level of inflation. A concept of equilibrium acknowledging this fact, and requiring that agents put some weight on any of the possible second-period equilibrium price vectors is developed. Such an equilibrium is shown to exist, and is illustrated by an example.This a revised version of chapter three of my Ph.D. dissertation. I would like to thank David Cass, Atsushi Kajii, George Mailath and Shinichi Suda for helpful discussions and comments. Thanks are also due to Jean-Michel Grandmont who pointed out mistakes in a previous version. All remaining mistakes are of course my own. Financial support from a CARESS scholarship at the University of Pennsylvania is gratefully acknowledged.     

Engel’s curve and product differentiation: A dynamic analysis of the effects of quality on consumer’s choice

The application of Engel’s Curve in a single-product perspective may dramatically change the role of quality in affecting the dynamics of economic performance. This paper introduces a specification of preferences that regards quality as luxury, and quantity as necessary. The analysis is carried out by using a framework similar to Grossman’s and Helpman ’s (1991), while quality is defined as in Stokey (1988). The resulting consumer’s demand crucially depends on quality. Quality is potentially able to prevent the process, implied by neoclassical models, that leads the value of consumption goods to decline over time. By doing so, quality also affects the consumption bundle shares and the variety-specific consumption growth rates, thus influencing all dynamic quantitative variables of the economy. I thank Professor Beniamino Moro for his guidance and encouragement. I thank Stephen Wright for his comments and suggestions. I have benefited from the support of Alessio Moro, Dario Unali, Debora Fletcher, Emilio Merella, Esteban Jaimovich, Francesca Lamanna, Matteo Bellinzas, Mauro Merella and all my friends. I am also indebted to Professor Cuong Le Van and Professor Stephen Parente for their advice. I thank two anonymous Referees for their useful remarks.     

Product differentiation and competitive selection

By studying the effect of different patterns of demand in an evolutionary selection model this paper shows how product differentiation reduces competitive selection pressure and thus increases the chances for the coexistence of firms. With the example of a duopoly it shows that: (1) a monopoly is the likely outcome of competition in homogeneous products, (2) although product differentiation does not preclude a monopoly it greatly improves the chances for the stable coexistence of firms in the long run, and (3) the more differentiated the products, the more stable the duopoly. JEL Classification: B52, L11 This study has benefited from insightful comments and suggestions of two anonymous referees as well as from discussions with Michael Peneder, Werner H?lzl, and Harry Bloch. I would also like to thank Dennis C. Mueller and Gustav Feichtinger for supervising my doctoral thesis preceding this paper.     

An inner core equivalence theorem

Summary We extend the notion of the inner core of a finite economy to a large economy. We prove that competitive allocations and the core coincide with the inner core.This is based on Chapter 5 of my Ph.D thesis. I am indebted to my thesis advisor, Lloyd S. Shapley, for his guidance. Discussions with Michael Balch are gratefully acknowledged. I also thank Charles Stuart, Nicholas C. Yannelis and an anonymous referee for comments and suggestions that greatly improved the paper.     

On the constancy of bribe-proof solutions

Summary. We consider the problem of choosing one point in a set of alternatives when monetary transfers are possible. In this context, Schummer (2000) shows that a social choice function must be a constant function if manipulation through bribes is ruled out. But he requires two kinds of domain-richness conditions. One is either smooth connectedness or the finiteness of the set of alternatives and the other is monotonical closedness. However, dispensing with the former condition, we alternatively prove the same result under a weaker condition than monotonical closedness. Received: April 11, 2000; revised version: February 25, 2002 RID="*" ID="*" This paper received the Osaka University Institute of Social and Economic Research Moriguchi Prize in January 2001. I am grateful to Prof. Ryoichi Nagahisa, Prof. Tatsuyoshi Saijo, Prof. Ken-ichi Shimomura, Prof. Ken Urai, and especially two anonymous referees for their useful and helpful comments and suggestions. I am a Research Fellow of the Japan Society for the Promotion of Science.     

Budget constraint of a firm and economic theory

Summary Firms in reality are subject to budget constraints which general equilibrium theorists have paid little attention. Using Morishima (1950, 1992) model, this paper deals with firms that are subject to budgets pertaining to sales and investment decisions, and proves the existence of a general equilibrium. We show that an economy with firms subject to budgets does not necessarily satisfy the efficiency proposition, and clarify how the total profit maximum condition in the Arrow-Debreu (1954) type economy ensures an efficiency in a limited dynamic sense.The author is grateful to Professors J. Iritani, H. Nagatani, and K. Urai who gave useful comments on occasions of Saturday Workshop on Economic Theory and Mathematics. He is also grateful to Professor M. Kaneko for his useful comments on an earlier version of the paper Kuga (1993), to which this article is closely related.     

IS THERE A (DOWNWARD SLOPING) DEMAND CURVE FOR VOLUNTEER LABOUR?

ABSTRACT * * I would like to thank the Indiana University Center on Philanthropy and the Irwin Foundation for financial support for my dissertation, which led to many of the ideas contained in this paper, as well as my dissertation advisors at Boston College. I would also like to thank my colleagues at John Carroll University and at the Mandel Center for Nonprofit Organizations at Case Western Reserve University, for their advice and comments on previous versions of this paper. All errors, however, remain my own responsibility.
: Are organizations that use volunteers content to accept all of the volunteer labour offered to them, or do they make some sort of demand-side decision as to how much volunteer labour to use? This paper looks for evidence of such a demand curve for volunteer labour in data collected by the Urban Institute in the early 1980s. Evidence is found that organizations are consistent over time in their use of volunteer labour.     

Coalition-proof supply function equilibria under capacity constraints

Whereas in the absence of capacity constraints the Cournot outcome is the unique coalition-proof supply function equilibrium outcome, the presence of capacity constraints may enlarge the set of equilibrium outcomes. Interestingly, if capacities are sufficiently asymmetric the new equilibrium prices are below the Cournot price. These results have important implications for merger and privatization policies: specifically, capacity divestiture will not necessarily imply lower market prices.This article is based on the second chapter of my PhD dissertation. I benefited from the comments and suggestions of Diego Moreno and Bill Hogan. I thank three anonymous referees for helpful comments. Seminar audiences at Carlos III and Harvard are gratefully acknowledged. The author is currently a Repsol YPF fellow at the Harvard John F. Kennedy School of Government. I am grateful to the Repsol YPF-Harvard Fellowship Program for financial support.     

The theoretical bases of economic policy: the Schumpeterian perspective

The central role of economic policy in an evolutionary environment is stressed. Based on a Schumpeterian view the theoretical foundations of such a policy are discussed. This investigation leads to the result that not general rules satisfying and maintaining equilibrium are required but a constant watchfulness, reaction, and, if possible, anticipation of what happens in the economy.Revised and extended version of a lecture given at the Universities of Augsburg and Munich in the spring of 1990. I want to thank Professor Karl W. Roskamp, for a critical reading of an earlier draft. My special thanks are due to my colleague Carl Simon, Professor of Mathematics and Economics at The University of Michigan, who helped me in an essential way with my understanding of what the latest developments in the analysis of dynamic systems are all about.