Are we nice(r) to nice(r) people?—An experimental analysis

We experimentally investigate whether individuals can reliably detect cooperators (the nice(r) people) in an anonymous decision environment involving “connected games.” Participants can condition their choices in an asymmetric prisoners’ dilemma and a trust game on past individual (their partner’s donation share to a self-selected charity) and social (whether their partner belongs to a group with high or low average donations) information. Thus, the two measures of niceness are the individual donation share in the donation task, and the cooperativeness of one’s choice in the two games. We find that high donors achieve a higher-than-average expected payoff by cooperating predominantly with other high donors. Group affiliation proved to be irrelevant. Electronic Supplementary Material Supplementary material is available in the online version of this article at . JEL Classification C91, C72, D3     

Human–capital investment and the wage gap

Summary. According to empirical studies, the wage differential by skills evolved non–monotonically in the past decades although the relative supply of skilled labor steadily increased. The present paper provides a theoretical explanation for this finding. In our setting, technological change intertemporally alters the human–capital investment incentives of heterogeneous individuals. As a consequence of changing incentives, the time path of the relative wage is U–shaped while there is a rise in the share of skilled workers. Received: November 28, 2000; revised version: January 30, 2001     

Competitive search markets for durable goods

Summary. This paper considers a dynamic version of Akerlof's (1970) lemons problem where buyers and sellers must engage in search to find a trading partner. We show that if goods are durable, the market itself may provide a natural sorting mechanism. In equilibrium, high-quality goods sell at a higher price than low-quality goods but also circulate longer. This accords with the common wisdom that sellers who want to sell fast may have to accept a lower price. We then compare the equilibrium outcomes under private information with those under complete information. Surprisingly, we find that for a large range of parameter values the quilibrium outcomes under the two information regimes coincide, despite the fact that circulation time is used to achieve separation. Received: August 24, 2000; revised version: October 24, 2000     

How to control a chaotic economy?

An economic system which exhibits chaotic behaviour has been stabilized on various periodic orbits by use of the Ott-Grebogi-Yorke method. This procedure has been recently applied to controlling chaotic phenomena in physical, chemical and biological systems. We adopt this method successfully for Feichtinger's generic model of two competing firms with asymmetrical investment strategies. We show that the application of this control method to the particular economic process considered brings a substantial advantage: one can easily switch from a chaotic trajectory to a regular periodic orbit and simultaneously improve the system's economic properties. Numerical simulations are presented in order to illustrate the effectiveness of the whole procedure.The work was supported by the Alexander von Humboldt-Stiftung and by the Polish National Council (KBN) Grant No 2 P302 038 04.     

Identification and Measurement of Australian Consumer Sentiment

This article was prepared by Dr L. V. Defris and J. S. McDonnell of the Institute research staff. The authors wish to thank Professor R. F. Henderson and Dr P. J. Sheehan for their helpful comments.     

Analysis of Austrian stocks: Testing for stability and randomness

This paper is concerned with subjecting two popular assumptions about the behavior of stock market prices to empirical tests: first, the random walk hypothesis developed by Bachelier (1900), Osborne (1959), and Mandelbrot (1963); second, the stable distributions hypothesis by Mandelbrot (1963) and Fama (1965). For this purpose, ten time series from the Vienna Stock Exchange were used. The first hypothesis was tested using both non-parametric and parametric methods. To obtain evidence with regard to the seond hypothesis, a graphical procedure and statistical estimation on the basis of the empirical characteristic function were applied. On analysis of our data, it turned out that, at least for the time period under consideration (1985–1990), severe doubts are cast on the above assumptions.We gratefully acknowledge the help of Peter Mitter, Institute for Advanced Studies, and Franz Köstl, Österreichische Kontrollbank, who provided us with the necessary data, and the comments of the anonymous referees.     

On the theory of cost sharing

This paper investigates efficiency and equitability issues given a cost sharing method in an economy with a public commodity. We study the concept of a -cost share equilibrium and examine the set of all equilibrium allocations. Finally, we devise a mechanism to implement -cost share equilibria as strong equilibria of an associated non-cooperative game.This paper was written while Shlomo Weber was visiting the University of Bonn. Financial support from theSonderforschungsbereich 303 is gratefully acknowledged. We also would like to thank Dieter Bös for valuable comments.