Deterministic evolutionary dynamics: A unifying approach

We tackle three components of evolutionary modelling: payoffs, dynamical systems and equilibrium concepts. Firstly, we merely require that fitness functions are continuous. Secondly, we examine very general classes of dynamics. Thirdly, we give useful parallels to the Nash equilibrium and the evolutionarily stable strategy. Under (weakly) sign-compatible dynamics the change in population share of every (at least one) subgroup present in the population corresponds in sign with its relative fitness. At a saturated equilibrium, each subgroup with positive population share has highest fitness. We examine two evolutionary stability concepts: the evolutionarily stable equilibrium and the generalized evolutionarily stable state.     

Walras and Darwin: an odd couple?

General equilibrium theory and the evolutionary branches of economics and game theory take rather opposite positions in the spectrum covered by the economic science. However, we reveal and explore analogies between Darwinian dynamics and Walrasian tatonnement processes for pure exchange economies, as well as further analogies implied by these.     

Feel Good,Do-Good!? On Consistency and Compensation in Moral Self-Regulation

Studies in the behavioral ethics and moral psychology traditions have begun to reveal the important roles of self-related processes that underlie moral behavior. Unfortunately, this research has resulted in two distinct and opposing streams of findings that are usually referred to as moral consistency and moral compensation. Moral consistency research shows that a salient self-concept as a moral person promotes moral behavior. Conversely, moral compensation research reveals that a salient self-concept as an immoral person promotes moral behavior. This study’s aim was to integrate these two literatures. We argued that compensation forms a reactive, “damage control” response in social situations, whereas consistency derives from a more proactive approach to reputation building and maintenance. Two experiments supported this prediction in showing that cognitive depletion (i.e., resulting in a reactive approach) results in moral compensation whereas consistency results when cognitive resources are available (i.e., resulting in a proactive approach). Experiment 2 revealed that these processes originate from reputational (rather than moral) considerations by showing that they emerge only under conditions of accountability. It can thus be concluded that reputational concerns are important for both moral compensation and moral consistency processes, and that which of these two prevails depends on the perspective that people take: a reactive or a proactive approach.     

Being “in Control” May Make You Lose Control: The Role of Self-Regulation in Unethical Leadership Behavior

In the present article, we argue that the constant pressure that leaders face may limit the willpower required to behave according to ethical norms and standards and may therefore lead to unethical behavior. Drawing upon the ego depletion and moral self-regulation literatures, we examined whether self-regulatory depletion that is contingent upon the moral identity of leaders may promote unethical leadership behavior. A laboratory experiment and a multisource field study revealed that regulatory resource depletion promotes unethical leader behaviors among leaders who are low in moral identity. No such effect was found among leaders with a high moral identity. This study extends our knowledge on why organizational leaders do not always conform to organizational goals. Specifically, we argue that the hectic and fragmented workdays of leaders may increase the likelihood that they violate ethical norms. This highlights the necessity to carefully schedule tasks that may have ethical implications. Similarly, organizations should be aware that overloading their managers with work may increase the likelihood of their leaders transgressing ethical norms.     

Social dilemmas,time preferences and technology adoption in a commons problem

Agents interacting on a body of water choose between technologies to catch fish. One is harmless to the resource, as it allows full recovery; the other yields high immediate catches, but low(er) future catches. Strategic interaction in one ‘objective’ resource game may induce several ‘subjective’ games in the class of social dilemmas. Which unique ‘subjective’ game is actually played depends crucially on how the agents discount their future payoffs. We examine equilibrium behavior and its consequences on sustainability of the common-pool resource system under exponential and hyperbolic discounting. A sufficient degree of patience on behalf of the agents may lead to equilibrium behavior averting exhaustion of the resource, though full restraint (both agents choosing the ecologically or environmentally sound technology) is not necessarily achieved. Furthermore, if the degree of patience between agents is sufficiently dissimilar, the more patient is exploited by the less patient one in equilibrium. We demonstrate the generalizability of our approach developed throughout the paper. We provide recommendations to reduce the enormous complexity surrounding the general cases.     

On a two regime model of the Dutch export market

Summary About a decade ago Batchelor presented an interesting model for the export market of UK industry in the period 1948–1975. In this paper a corrected version of Batchelor's model is used to explain Dutch exports from 1962 to 1981. The results are compared with straightforward alternatives to obtain an indication of the relevance of the model in practice. Our conclusion is that the model does not explain exports behaviour better than simple alternatives. For some variables even implausible elasticities are obtained.The authors gratefully acknowledge the computational assistance of Mr. R. van Dal and the valuable comments of Mr. D.A.G. Draper from the CPB, Professor J. Pen and two anonymous referees.