Neighborhood structure and the evolution of cooperation

This paper deals with the problem of explaining the survival of cooperative behavior in populations in which each person interacts only with a small set of social ‘neighbors’, and individuals adjust their behavior over time by myopically imitating more successful strategies within their own neighborhood. We identify two parameters—the interaction radius and the benefit–cost ratio—which jointly determine whether or not cooperation can survive. For each value of the interaction radius, there exists a critical value of the benefit–cost ratio which serves as the threshold below which cooperation cannot be sustained. This threshold itself declines as the interaction radius rises, so there is a precise sense in which dense networks are more conducive to the evolution of cooperation.     

Existence of Equilibria in Matching Models of Money: A New Technique

This paper develops a new technique for proving the existence and indeterminacy of monetary equilibria in money search models with divisible money. Our technique is substantially simpler than standard constructive proofs in the literature. This paper is based on the second half of Kamiya and Shimizu (2002). We are very grateful to the associate editor and an anonymous referee of this journal for their very detailed suggestions and comments. This research is financially supported by Grant-in-Aid for Scientific Research from JSPS and MEXT. The second author also acknowledges the financial support by Zengin Foundation for studies on Economics and Finance.     

The Borda rule,Condorcet consistency and Condorcet stability

Summary. The Borda rule is known to be the least vulnerable scoring rule to Condorcet inconsistency, Saari (2000). Such inconsistency occurs when the Condorcet winner (the alternative which is preferred to any other alternative by a simple majority) is not selected by the Borda rule. This note exposes the relationship between the Borda rule and the Condorcet q-majority principle as well as the Condorcet q-majority voting rule. The main result establishes that the Borda rule is Condorcet q-majority consistent when where k is the number of alternatives. The second result establishes that is the minimal degree of majority decisiveness corresponding to the Borda rule under sincere voting. The same majority is required to ensure decisiveness under the Borda rule and to ensure that a q-rule (the generalized q-majority Condorcet rule) is a voting rule. Received: April 8, 2002; revised version: July 17, 2002 Correspondence to:S. Nitzan     

Environmental tax policy in a model of growth cycles

Summary. The purpose of this paper is to consider environmental taxation which would control emissions of firms in a model of growth cycles. In the model presented below, the economy may experience two phases of growth and environmental quality: “the no-innovation growth regime” and “the innovation-led growth regime”. Aggregate capital and environmental quality remain constant in the no-innovation growth regime, while they perpetually increase in the innovation-led growth regime. The paper shows that the tax plays a key role in determining whether the economy stably converges to one of the two regimes or fluctuates permanently between them. It also shows that there is a critical level of the tax and that the economy obtains higher growth rates of capital and environmental quality by raising (or reducing) the tax if the initial tax is below (or above) the critical level. Received: April 2, 2001; revised version: March 21, 2002 RID="*" ID="*" This research reported here was conducted within the research project “Project on Intergenerational Equity” at Institute of Economic Research, Hitotsubashi University. I am deeply grateful to an anonymous referee for his or her insightful comments, which greatly improved the paper. I also thank Hiroshi Honda, Yasuo Maeda, Yuji Nakayama, and participants in workshops at Hitotsubashi University, Kyoto University, Nagoya University, Osaka University, University of Tsukuba, Yokohama National University, and University of Tokyo for their valuable comments and suggestions. Any remaining errors are mine.     

Amended final-offer arbitration over an uncertain value: A comparison with CA and FOA

Arbitration is increasingly employed to resolve disputes. Two arbitration mechanisms, conventional arbitration (CA) and final-offer arbitration (FOA) are commonly utilized, but previous theoretical and empirical research has found that they are unsatisfactory. Several alternative mechanisms have been proposed, but ultimately laboratory research has found that they do not offer an improvement. An exception is amended final-offer arbitration (AFOA), which not only has desirable theoretical properties but also has been demonstrated to outperform FOA in the laboratory. This study provides a direct laboratory comparison of AFOA with CA. Also, by utilizing an environment with an uncertain payoff to one of the parties, this study tests the robustness of AFOA’s performance relative to FOA. The results indicate that AFOA does outperform FOA, but that AFOA is only weakly better than CA. JEL Classification C7, C9, J5, K4     

Commodity price cycles and heterogeneous speculators: a STAR–GARCH model

We propose an empirical commodity market model with heterogeneous speculators. While the power of trend-extrapolating chartists is constant over time, the symmetric impact of stabilizing fundamentalists adjusts endogenously according to market circumstances: Using monthly data for various commodities such as cotton, sugar or zinc, our STAR–GARCH model indicates that their influence positively depends on the distance between the commodity price and its long-run equilibrium value. Fundamentalists seem to become more and more convinced that mean reversion will set in as the mispricing enlarges. Commodity price cycles may thus emerge due to the nonlinear interplay between different trader types. The paper represents the authors’ personal opinion and does not necessarily reflect the views of the Deutsche Bundesbank.     

Regulatory and environmental effects on public transit efficiency: a mixed DEA-SFA approach

This paper assesses the impact of regulatory and environmental factors and statistical noise on the efficiency of public transit systems within a DEA-based framework. Using a panel of Italian companies, we implement a DEA-SFA mixed approach based on [H.O. Fried et al. (2002) Journal of Productivity Analysis, 17(1–2), 157–174] to decompose DEA inefficiency measures into three components: exogenous effects, managerial inefficiency and stochastic events. Besides providing evidence on the determinants of input-specific efficiency differentials across companies, the results point out that managerial skills play a minor role, and emphasize the relevance of regulatory policies aimed at replacing cost-plus subsidization with high-powered incentive contracts as well as improving environmental conditions of public transit networks.      

The establishment-size wage premium: evidence from European countries

This study examines the magnitude and determinants of the establishment-size wage premium in five European countries using a unique harmonised matched employer–employee data set (the 1995 European Structure of Earnings Survey). This data set enables to test the validity of various traditional explanations of the size wage gap (i.e. the labour quality hypothesis, the theory of compensating wage differentials, the role of monitoring and institutions) and of more recent hypotheses (i.e. size differences in job stability and in the concentration of skilled workers). We find some support for traditional explanations, but there remains a significant wage premium for workers employed in large establishments. Further results indicate that the magnitude of this premium fluctuates substantially across countries and appears to be negatively correlated with the degree of corporatism.     

Estimating exchange rate dynamics with diffusion processes: an application to Greek EMU data

Recently various exchange rate models capturing the dynamics during the transition from an exchange rate arrangement of floating rates into a currency union have been derived. Technically, these stochastic equilibrium models are diffusion processes which have to be estimated by discretely sampled observations. Using daily exchange rate data prior to the Greek EMU-entrance on 1 January 2001, we develop a rigorous estimation procedure. Our estimates point to an increasing interventionist economic policy in the run-up to the Greek EMU entrance. A comparison of this econometric indication with policy information provided (ex-post) by the Bank of Greece (BoG) in its Annual Report 2000 reveals that the BoG indeed pursued such an active policy stance (so-called institutional frontloading strategies).      

Evaluating the Validity of Self-Reported Deviant Behavior Using Vignette Analyses

In this paper, the validity of vignette analyses of various forms of deviant behavior in the presence of opportunities is analyzed on the basis of ideas derived from cognitive psychology. Abelson’s Script Theory together with insights into human memory of visual and verbal information, allow the assumption that vignette analyses using visual stimuli are valid measures of deviant behavior in particular. The study includes an empirical examination of these ideas (n = 450). Nonparticipant observations and vignette analyses with visual and verbal material were carried out with regard to three forms of deviant behavior occurring in the presence of opportunities presenting themselves in everyday life. Observed and self-reported frequencies of deviant behavior or deviant intentions were counted and cross-tabulated. Log-linear analyses with dummy coding using observation data as reference category were run. Data analyses yielded the result that frequencies of deviant behavior were related to the techniques of data collection under consideration. Especially vignette analyses of the return of ‘lost letters’ that use both visual and verbal stimuli overestimate ‘actual’ (i.e. observed) return rates. This result is discussed with regard to the underlying methodological assumptions as well as its implications.