Regulating Availability with Demand Uncertainty

Abstract. I evaluate a new German regulation that requires retail discounters to guarantee the availability of their products in bargain sales. The regulation is meant to prevent loss leaders. Retailers undermine the regulation's rationale by claiming that rationing is due to demand uncertainty. This paper shows that under demand uncertainty the regulation has ambiguous welfare effects. Effectively, it raises production, which, under imperfect competition, tends to be beneficial. However, the regulation overshoots and decreases welfare if it requires availability for a state of high demand that is relatively unlikely. In this case more sophisticated regulation is required.     

Sustainability and consumption

We consider the implications of the three pillars of sustainability (environment, economy and social justice) on consumption in a wealthy country. Building a theoretical model that includes consumers, business, government, the environment, and economic and political relations between nations, we explore how sustainability should affect the consumption behavior of consumers, charitable aid to poorer countries, and responsible environmental practices by businesses. Our model enables us to provide normative implications for consumers, society and business. Importantly, we assume that all stakeholders will optimize their self-interest, and that altruism will only partly explain behavior consistent with sustainability. Among the more non-obvious findings are that (1) the poorer the poor countries are, the less the rich countries should consume, (2) the more sensitive the global political climate is to economic inequity between the rich and poor nations, the less the rich countries should consume, and (3) if aid to poor countries is effective enough, then the more materialistic the society is, the more charitable aid it should give. We also confirm a number of more intuitive findings, such as that business should use more green technology as the taxes on pollution and/or efficiency of green technology increase, and the more resource-intensive consumption is, the less consumers should consume. Taken as a whole, the findings imply that societal consumption patterns should be sensitive to aspects of environmental impact and social justice, even if altruistic motivations are absent.     

Functions of scenarios in transition processes

Given the interplaying tendencies of economic decline, social instability, and environmental depletion, any transition towards sustainable development faces a challenging task. To successfully cope with this complexity requires transition management. Integrated approaches for supporting sustainability transitions have been elaborated in the last years. Future studies and scenario construction are regarded as essential components in these approaches. However, the related studies in this field have focused either on a specific type of transition process, or on decision support in a different contextual process, or on a specific function of scenarios. Thus, an evaluation of the wide range of viewpoints on the functions of scenarios with respect to the requirements for transition management is still missing. In this paper, we systematically elaborate upon the functions for transition management that scenarios can fulfil. The developed concept is applied to five empirical scenario studies supporting transition processes on the national, regional and local level in Switzerland. The paper contributes to the development of a functional methodology of transition support, providing initial guidelines for answering the question of which method is appropriate for what type and phase of a transition process.     

Enumeration of Nash equilibria for two-player games

This paper describes algorithms for finding all Nash equilibria of a two-player game in strategic form. We present two algorithms that extend earlier work. Our presentation is self-contained, and explains the two methods in a unified framework using faces of best-response polyhedra. The first method lrsnash is based on the known vertex enumeration program lrs, for “lexicographic reverse search”. It enumerates the vertices of only one best-response polytope, and the vertices of the complementary faces that correspond to these vertices (if they are not empty) in the other polytope. The second method is a modification of the known EEE algorithm, for “enumeration of extreme equilibria”. We also describe a second, as yet not implemented, variant that is space efficient. We discuss details of implementations of lrsnash and EEE, and report on computational experiments that compare the two algorithms, which show that both have their strengths and weaknesses.