Trees and decisions

Summary. The traditional model of sequential decision making, for instance, in extensive form games, is a tree. Most texts define a tree as a connected directed graph without loops and a distinguished node, called the root. But an abstract graph is not a domain for decision theory. Decision theory perceives of acts as functions from states to consequences. Sequential decisions, accordingly, get conceptualized by mappings from sets of states to sets of consequences. Thus, the question arises whether a natural definition of a tree can be given, where nodes are sets of states. We show that, indeed, trees can be defined as specific collections of sets. Without loss of generality the elements of these sets can be interpreted as representing plays. Therefore, the elements can serve as states and consequences at the same time.Received: 23 January 2003, Revised: 2 November 2003, JEL Classification Numbers: C72, D70. Correspondence to: Klaus RitzbergerWe are grateful to Larry Blume, Ariel Rubinstein, Jörgen Weibull, an anonymous referee, and seminar participants at the universities of Vienna, Salamanca, and Heidelberg for helpful comments. Financial support from the Austrian Science Fund (FWF) under project P15281 is also gratefully acknowledged.     

Sectoral and aggregate technology growth in Spain

In this paper we analyze technological change in the Spanish economy by constructing adjusted Solow residuals, where the adjustment attempts to correct for the bias associated with the potential presence of imperfect competition, increasing returns, variable input utilization and, especially, sectoral reallocation of inputs across sectors. We refer to this modified Solow residual as a technology index. Sectoral reallocations and variable input utilization are key determinants of the differences between the aggregate Solow residual and the technology index resulting from the aggregation of estimated sectoral technological growth. We show that starting in the mid nineties, there has been a deceleration in the aggregate growth rate of technology which is basically due to the behaviour of the manufacturing sectors. Finally, our results imply that aggregate technology growth is less volatile than aggregate productivity as measured by the Solow residual.     

On the generic impossibility of truthful behavior: A simple approach

Summary We provide an elementary proof showing how in economies with an arbitrary number of agents an arbitrary number of public goods and utility functions quasi-linear in money, any efficient and individually rational mechanism is not strategy-proof for any economy satisfying a mild regularity requirement.The authors wish to thank William Thomson, Salvadpr Barberá, José Angel Silva and an anonymous referee for helpful comments. The remaining errors are our exclusive responsibility. Financial support from DGICYT under project PB 91-0756 and the Instituto Valenciano de Investigaciones Económicas is gratefully acknowledged.     

Modeling Cyclical Asymmetries in European Imports

This paper applies smooth transition models to capture the nonlinear behavior in the imports data of six major European economies and to assess whether such nonlinearities are related to business cycle asymmetries. Two classes of switch between regimes are considered: endogenously determined transition that assumes nonlinearities are generated by idiosyncratic components specific to foreign trade, and exogenous transition based on GDP growth as a more direct indicator of the cyclical state of the economy. The results support the proposition that the dynamics of imports are nonlinear. In Belgium, France, Spain, and the United Kingdom, regimes change over the business cycle, while in Germany and Italy the switch between regimes is endogenous. National characteristics play a role in defining the position of extreme regimes, the smoothness of the transition, and local dynamics within each state.Previous versions of this article have been presented at the 57th International Atlantic Economic Conference (Lisbon, Portugal, March 10–14, 2004) and at the VII Encuentro de Economía Aplicada (Vigo, Spain, June 3–5, 2004). The authors thank the conference participants and an anonymous referee for their comments.     

Strategic Environmental Standards, Wage Incomes and the Location of Polluting Firms

The purpose of this paper is tostudy how the choice of environmental standardsby governments is affected by the existence ofwage incomes when firms locations areendogenous. In developed countries labor isunionized, which allows positive wage incomesto arise. Thus, each government has incentivesto persuade firms to locate in its countrysince social welfare depends on suchincomes. But, as pollution damages theenvironment, each government will only try toattract polluting firms to thecountry, to obtain the wage incomes, whenthe valuation of environmental damage showsthat it is low.     

Austrian Economics and Public Choice

The Review of Austrian Economics -     

Stock prices,production and interest rates: Comparison of three European countries with the USA

This paper investigates the relationships between stock returns, changes in production, and changes in interest rates in three European countries: France, Germany, and the United Kingdom. The results obtained using annual data are much more conclusive than those obtained using quarterly data. Stock returns are affected by current changes in interest rates and by future changes in production. The dependence on changes in interest rates seems to be higher than on changes in production. Furthermore, the influence of future changes in production on stock returns diminishes substantially when contemporaneous changes in interest rates are taken into account. With reference to these points, the European markets behave in a similar fashion, but are in sharp contrast with the U.S. market.I am very grateful to Kay Davidson, Patric Hendershott and two anonymous referees for useful comments and suggestions. I am solely responsible for all remaining errors.     

Sources of gains from international portfolio diversification

This paper looks at the determinants of country and industry specific factors in international portfolio returns using a sample of forty eight countries and thirty nine industries over the last three decades. Country factors have remained relatively stable over the sample period while industry factors have significantly increased during the last decade and dropped again since 2000. The importance of industry and country factors is correlated with measures of economic and financial international integration and development. We find that financial market globalization is the main driving force behind the changes in relative magnitude of the different shocks. Country factors are smaller for countries integrated in world financial markets and have declined as the degree of financial integration and the number of countries pursuing financial liberalization has increased. Higher international financial integration within an industry increases the importance of industry factors in explaining returns. Economic integration of production also helps in explaining returns. Countries with a more specialized production activity have higher country shocks.