Industry dynamics: Foundations for models with an infinite number of firms

This paper explores the connection between three important threads of economic research offering different approaches to studying the dynamics of an industry with heterogeneous firms. Finite models of the form pioneered by Ericson and Pakes (1995) capture the dynamics of a finite number of heterogeneous firms as they compete in an industry, and are typically analyzed using the concept of Markov perfect equilibrium (MPE). Infinite models of the form pioneered by Hopenhayn (1992), on the other hand, consider an infinite number of infinitesimal firms, and are typically analyzed using the concept of stationary equilibrium (SE). A third approach uses oblivious equilibrium (OE), which maintains the simplifying benefits of an infinite model but within the more realistic setting of a finite model. The paper relates these three approaches. The main result of the paper provides conditions under which SE of infinite models approximate MPE of finite models arbitrarily well in asymptotically large markets. Our conditions require that the distribution of firm states in SE obeys a certain “light-tail” condition. In a second set of results, we show that the set of OE of a finite model approaches the set of SE of the infinite model in large markets under a similar light-tail condition.     

Rolle der Kohle im weltweiten Energiemix

In the past decade, coal was the energy resource boasting the strongest absolute growth world-wide. Most of the coal is used in the countries where it is extracted and 15% of coal production is traded on international markets. With a share of 41% coal is the No. 1 fuel source in global power generation. The benefits offered by coal are security of supply and lower prices than that of rival energy carriers. In the main scenario of the 2010 World Energy Outlook, the International Energy Agency assumes that until 2035 coal will have to make a growing absolute contribution to the 75% increase in global power generation. According to this assumption, coal, accounting for 32%, will make the same contribution as renewable resources in 2035.     

Different but Similar: Geothermal Energy and the Role of Politics in Germany, Iceland and the United States

This article looks into the role of the state in geothermal energy development. Based on the findings in three countries studied, it demonstrates that the demand for political intervention is strongly tied to the state of the technological and industry development. While government’s most important role in the early stages is R&D-support and regulatory guidelines, the relevance of market-based instruments and network support kicks in later. Between these two phases is a period where both ‘toolkits’ of political intervention (direct investment and indirect support efforts) have to be provided by state actors. Furthermore, the project timeline has to be kept in mind. Supporting project economics alone is not sufficient if project-internal barriers exist that cannot be overcome without specific support. The installation of an insurance scheme for dry wells in Germany and a similar mechanism in Iceland can be regarded as outstanding examples of this. However, it is important to note that geothermal energy generally will not be developed without strong public support in all development phases. The common cross-case barriers alone are sufficient for project developers and investors to be cautious about entering the industry. But if governments engage with the right instruments at the right time, there is reason to say that geothermal energy can provide a contribution to the energy turn towards renewable energies in many parts of the world, even apart from high-enthalpy regions.     

Modelling non-competitive behavior in commodity markets: A game theoretic approach

In this paper, we provide a coalitional alternative to the perfectly competitive and purely non-cooperative assumptions commonly employed in the modelling of commodity markets. These assumptions of perfect competition or pure non-cooperation are usually imposed exogenously without providing an economic basis for assuming why firms that could stand to gain by cooperating would not in fact do so. Three behavioral rules embodied in three different cooperative games are discussed in this paper and a methodology for predicting the coalition structures that would result from each of these is offered. By applying these games to the US copper industry of the 1970's, we show that the theory of games can be profitably employed in conjunction with the traditional institutional approach of industrial organization to yield useful economic predictions.The author is grateful to two anonymous referees whose comments led to a considerably improved version of the paper.     

Exact welfare measures and economic index numbers

Summary Welfare measures and economic index numbers are usually defined by formulae or by verbal definitions. This paper develops characterizations of some important measures and corresponding index numbers by an axiomatic approach. These results facilitate the choice between different welfare indicators, and they show the strength of assumptions like MM and RM. Indeed these properties rule out CI and yield the Hicksian measures EV and CV, and their dual counterparts, respectively. At the same time one can conclude that these measures have to be used very carefully, if one considers the limitations implied by these properties.The author would like to thank Dieter Elixmann, Sigrid Müller, and an anonymous referee for valuable suggestions and criticism.