Evolutionary stable stock markets

Summary. This paper shows that a stock market is evolutionary stable if and only if stocks are evaluated by expected relative dividends. Any other market can be invaded in the sense that there is a portfolio rule that, when introduced on the market with arbitrarily small initial wealth, increases its market share at the incumbents expense. This mutant portfolio rule changes the asset valuation in the course of time. The stochastic wealth dynamics in our evolutionary stock market model is formulated as a random dynamical system. Applying this theory, necessary and sufficient conditions are derived for the evolutionary stability of portfolio rules when relative dividend payoffs follow a stationary Markov process. These local stability conditions lead to a unique evolutionary stable portfolio rule according to which assets are evaluated by expected relative dividends (with respect to the objective probabilities).Received: 7 October 2003, Revised: 18 January 2005, JEL Classification Numbers: G11, D52, D81. Correspondence to: Klaus Reiner Schenk-HoppéWe are grateful to Jarrod Wilcox and William Ziemba for valuable comments. Financial support by the national center of competence in research Financial Valuation and Risk Management is gratefully acknowledged. The national centers in research are managed by the Swiss National Science Foundation on behalf of the federal authorities.     

Incorporating positions into asset pricing models with order-based strategies

The paper addresses the problem of agent-based asset pricing models with order-based strategies that the implied positions of the agents remain indeterminate. To overcome this inconsistency, two easily applicable risk aversion mechanisms are proposed which modify the original actions of a market maker and the speculative agents, respectively. Here the concepts are incorporated into the classical Beja–Goldman model. For the deterministic version of the thus enhanced model a four-dimensional mathematical stability analysis is provided. In a stochastic version it is demonstrated that jointly the mechanisms are indeed able to keep the agents’ positions within bounds, provided the corresponding risk aversion coefficients are neither too low nor too high. A similar result holds for the misalignment of the market price. We wish to thank two anonymous referees for their observations and detailed comments. Financial support from EU STREP ComplexMarkets, contract number 516446, is gratefully acknowledged.     

Equilibrium selection under cyclical disequilibrium dynamics

The paper considers an abstract economy exhibiting strategiccomplementarity and multiple, isolated Nash equilibria. It introducesexplicit disequilibrium adjustments, which are based on a combinationof adaptive and extrapolative forecasts. In this way the locallystable equilibria are typically approached in a cyclical manner.Globally, the phenomenon of overshooting increases the likelinessof regime shifting in response to exogenous shocks. In particular,even undampened cyclical behaviour is possible after a one-timeshock. A general conclusion is that the strong propagation effectsmake the economy much more susceptible to path-dependence thanit would be under the equilibrium selection hypothesis conventionallyemployed in this framework.     

Politicians and Preferences of the Voter Majority: Does Gender Matter?

Does the gender of political representatives affect the extent to which they adhere to the voter majority's preferences? By matching individual male and female representatives' votes on legislative proposals with real referendum outcomes on the same issues, we obtain a direct measure of divergence. We find that female and male representatives adhere equally close to the majority's preferences if party affiliations are taken into account. This suggests that observed gender differences with respect to the national majority of voters may be reduced to an ideological left–right dimension.     

Value Creation by Toolkits for User Innovation and Design: The Case of the Watch Market

This study analyzes the value created by so-called "toolkits for user innovation and design," a new method of integrating customers into new product development and design. Toolkits allow customers to create their own product, which in turn is produced by the manufacturer. In the present study, questions asked were (1) if customers actually make use of the solution space offered by toolkits, and, if so, (2) how much value the self-design actually creates. In this study, a relatively simple, design-focused toolkit was used for a set of four experiments with a total of 717 participants, 267 of whom actually created their own watches. The heterogeneity of the resulting design solutions was calculated using the entropy concept, and willingness to pay (WTP) was measured by the contingent valuation method and Vickrey auctions. Entropy coefficients showed that self-designed watches vary quite widely. On the other hand, significant patterns still are visible despite this high level of entropy, meaning that customer preferences are highly heterogeneous and diverse in style but not completely random. It also was found that consumers are willing to pay a considerable price premium. Their WTP for a self-designed watch exceeds the WTP for standard watches by far, even for the best-selling standard watches of the same technical quality. On average, a 100% value increment was found for watches designed by users with the help of the toolkit. Taken together, these findings suggest that the toolkit's ability to allow customers to customize products to suit their individual preferences creates value for them in a business-to-consumer (B2C) setting even when only a simple toolkit is employed. Alternative explanations, implications, and necessary future research are discussed.     

Inflation and distribution in a Keynes-Wicksell model of the business cycle

The paper integrates a Kaleckian hypothesis of markup pricing and markup adjustments into a dynamic IS-LM model of Keynes-Wicksell type. Local stability and instability are characterized by different speeds of adjustments in the adaptive expectations of inflation. Application of the Hopf bifurcation theorem proves existence of periodic orbits in the three-dimensional state space. The global dynamics is investigated by means of computer simulations. A suitable modification of the rule of adaptive expectations checks the explosive tendencies and gives rise to an apparently unique and stable limit cycle. It is sketched how the evolution of the most important variables over this growth cycle compares to empirical stylized facts.     

Stabilitätseffekte konjekturaler Variation und steigender Grenzkosten in Preisoligopolen

Ohne Zusammenfassung     

Mass or Only “Niche Customization”? Why We Should Interpret Configuration Toolkits as Learning Instruments

In order to configure individual products according to their own preferences, customers are required to know what they want. While most research simply assumes that consumers have sufficient preference insight to do so, a number of psychologically oriented scholars have recently voiced serious concerns about this assumption. They argue that decades of consumer behavior research have shown that most consumers in most product categories lack this knowledge. Not knowing what one wants means being unable to specify what one wants—and therefore, they conclude, the majority of customers are unable to use configuration toolkits in a meaningful way. In essence, this would mean that mass customization should rather be termed “niche customization” as it will be doomed to remain a concept for a very small minority of customers only. This pessimism stands in sharp contrast to the optimism of those who herald the new possibilities enabled by advances in communication and production technologies as the dawn of a new era in new product development and business in general. Which position is right? In order to answer this question, this research investigates the role of the configuration toolkit. Implicitly, the skeptic position assumes that the individual customers' knowledge (or absence of knowledge) of what they want is an exogenous and constant term that does not change during the interaction with the toolkit. However, learning theories suggest that the customers' trial‐and‐error interaction with the configuration toolkit and the feedback information they receive should increase their preference insight. If this was true and the effect size strong, it would mean that low a priori preference insight does not impede customers to derive value from mass customization. Three experiments show that configuration toolkits should be interpreted as learning instruments that allow consumers to understand their preferences more clearly. Even short trial‐and‐error self‐design processes with conventional toolkits bring about substantial and time‐stable enhancements of preference insight. The value of this knowledge is remarkable. In the product category of self‐designed watches, the 10‐minute design process resulted in additional preference insight worth 43.13 euros on average or +66%, measured by incentive‐compatible auctions. A moderator analysis in a representative sample shows that the learning effect is particularly strong among customers who initially exhibit low levels of preference insight. These findings entail three contributions. First, it becomes evident that the interaction with mass customization toolkits not only triggers affective reactions among customers but also has cognitive effects—a response category not investigated before. Second, it suggests that the pessimism regarding the mass appeal of these toolkits is not justified—mass customization has the potential to truly deserve its name. The prerequisite for this, and this normative conclusion is the final contribution, is that the toolkit should not be interpreted as a mere interface for conveying preexisting preferences to the producer. Rather, it should be treated as a learning instrument. Several suggestions are made for how firms employing this innovative business model could design their toolkits towards this end.