The nature of the steady state in models of optimal growth under uncertainty

Summary. We study a one-sector stochastic optimal growth model with a representative agent. Utility is logarithmic and the production function is of the Cobb-Douglas form with capital exponent . Production is affected by a multiplicative shock taking one of two values with positive probabilities p and 1-p. It is well known that for this economy, optimal paths converge to a unique steady state, which is an invariant distribution. We are concerned with properties of this distribution. By using the theory of Iterated Function Systems, we are able to characterize such a distribution in terms of singularity versus absolute continuity as parameters and p change. We establish mutual singularity of the invariant distributions as p varies between 0 and 1 whenever . More delicate is the case . Singularity with respect to Lebesgue measure also appears for values such that . For and Peres and Solomyak (1998) have shown that the distribution is a.e. absolutely continuous. Characterization of the invariant distribution in the remaining cases is still an open question. The entire analysis is summarized through a bifurcation diagram, drawn in terms of pairs .Received: 9 April 2002, Revised: 29 October 2002, JEL Classification Numbers: C61, O41.Correspondence to: Tapan MitraThis research was partially supported by CNR (Italy) under the "Short-term mobility" program and by M.U.R.S.T. (Italy) National Group on "Nonlinear Dynamics and Stochastic Models in Economics and Finance" . We are indebted to Rabi Bhattacharya for providing us with the reference to Solomyak's (1995) paper. The present version has benefitted from comments by Mukul Majumdar and two anonymous referees.     

Environmental Regulation and Substitution Between Sources of Pollution: An Empirical Analysis of Florida’s Storage Tanks

Stringent and very specific environmental regulations may spur behavioral responses by the regulated entities that can offset the intended pollution control goals. I empirically examine the effects of regulating underground storage tanks for petroleum products and hazardous substances, focusing on their possible substitution or complementarity with a less stringently regulated alternative, aboveground tanks. Longitudinal county-level tank data from Florida reveal that the relationship between underground and aboveground tanks changed, from one of complementarity to one of substitution, after the regulations were issued. Tank installations are affected by resident characteristics that enter in the firms calculus of the damages from leaks.     

Trade and Renewable Resources in a Second Best World: An Overview

We provide an overview and introduction to the emerging field of trade and renewable resources, and discuss the potential impact of trade liberalization on welfare and resource conservation. A key factor determining the effect of trade reform is the institutional context or property rights regime, and our survey is organized such that it loosely follows the development of new insights with respect to institutions in this literature. This implies a transition from the benevolent planners model to the polar opposite benchmark of open access in the 1990s. Currently the pendulum is swinging back towards management and regulation, but institutions are treated as endogenous. We discuss and compare various key models in some detail and search for common ground between protagonists and antagonists of free trade. Paper based on Keynote address by Erwin Bulte, 12th Annual Conference of the European Association of Environmental and Resource Economists, Bilbao (Spain), June 28–30, 2003.     

Long memory in volatilities of German stock returns

We show that there is strong evidence of long-range dependence in the volatilities of several German stock returns. This will be done by applying a method using the difference of the classical log-periodogram regression estimator for the memory parameter and of the tapered periodogram based estimator. Both estimators give similar values for the memory parameter for each series and this indicates long memory. To support our findings we apply also a methodology using the sample variance and a wavelet based estimator to the data. Also these two methods show clear evidence of long-range dependence in the volatilities of German stock returns.First version received: December 2001/Final version received: March 2003The computational assistance of Eleni Mitropoulou and Björn Stollenwerck as well as the helpful comments of two unknown referees are gratefully acknowledged. Research supported by Deutsche Forschungsgemeinschaft under SFB 475. Stock returns were obtained from Deutsche Finanzdatenbank (DFDB), Karlsruhe.     

Assessing Voluntary Programs to Improve Environmental Quality

The last decade has seen a dramatic increase in the use of voluntaryapproaches (VAs) to environmental protection, which has spurned agrowing literature on the relative merits of voluntary vs. mandatoryapproaches. This paper draws on that literature to discuss both thetheoretical and empirical issues that arise in the evaluation orassessment of a particular VA. We consider both the environmentaleffectiveness and the efficiency of this policy approach. Our aim is toaid policymakers in evaluating a specific program or in thinking aboutthe use and design of a VA. We identify some key features that arelikely to increase both the effectiveness and the efficiency of VAs.     

Reinterpreting the performance of immigrant wages from panel data

Immigrants differ from the native born in terms of unobserved factors, such as motivation, and observed factors, including those related to the interruption of labour market activity and earning capacity, which may bias estimates of immigrant integration. Using panel data from the Survey of Labour and Income Dynamics, we show that using potential experience, rather than actual experience, exaggerates estimates of the disruption and recovery caused by immigration. More importantly, we find support for omitted variables bias, arising from unobserved fixed effects. Instrumental variable estimates for both pooled and separate samples of immigrant and native born men demonstrate a wage disadvantage for immigrants upon entry that persists through their lifetime. Standard estimates of a modest wage advantage for the children of immigrants also suffer from omitted variables bias arising from unobservables. Contrary to most of the literature to date, our instrumental variable estimates which allow for unobservable fixed effects suggest that immigrants never catch up to otherwise comparable native born workers, but their children do just as well. We would like to thank Statistics Canada for permitting access to the data and solving associated technical problems, the Prairier Centre for Research on Immigration and Integration for financial assistance, and Peter Schnabl for excellent research assistance. An earlier version of this paper was presented to the 10th International Conference on Panel Data in Berlin, July 5–6, 2002. The authors take sole responsibility for errors, omissions and interpretation of the data.     

Enforcing Emissions Trading when Emissions Permits are Bankable

We propose enforcement strategies for emissions trading programs with bankable emissions permits that guarantee complete compliance with minimal enforcement costs. Our strategies emphasize imperfect monitoring supported by a high unit penalty for reporting violations, and tying this penalty directly to equilibrium permit prices. This approach is quite different from several existing enforcement strategies that emphasize high unit penalties for emissions in excess of permit holdings. Our analysis suggests that a high penalty for excess emissions cannot be used to conserve monitoring effort, and that it may actually increase the amount of monitoring necessary to maintain compliance.The authors are grateful to Anthony Heyes and three anonymous referees for their valuable comments. Partial support for this research was provided by the Cooperative State Research Extension, Education Service, U. S. Department of Agriculture, Massachusetts Agricultural Experiment Station under Project No. MAS00871.     

A simple random assignment problem with a unique solution

Summary. All agents have the same ordinal ranking over all objects, receiving no object (opting out) may be preferable to some objects, agents differ on which objects are worse than opting out, and the latter information is private. The Probabilistic Serial assignment, improves upon (in the Pareto sense) the Random Priority assignment, that randomly orders the agents and offers them successively the most valuable remaining object. We characterize Probabilistic Serial by efficiency in an ordinal sense, and envy-freeness. We characterize it also by ordinal efficiency, strategyproofness and equal treatment of equals. Received: October 5, 1999; revised version: December 20, 2000     

Efficiency wages and union-firm bargaining with private information

We consider efficiency wage effects in a union-firm bargaining model with private information. We show that an increase in the efficiency wage effects does not necessarily increase the wage level at equilibrium, even when the wage bargaining with private information is close to one with complete information. However, if it is commonly known that the firm is stronger than the union and the demand is sufficiently elastic, then an increase in the efficiency wage effects increases for sure the wage at equilibrium.JEL Classification: J41, J50, J52We thank Juan Dolado and two anonymous referees for valuable comments. Vincent Vannetelbosch is Chercheur Qualifié at the Fonds National de la Recherche Scientifique. The research of Ana Mauleon has been made possible by a fellowship of the Fonds Européen du Développement Economique Régional (FEDER). Financial support from the Belgian French Communitys program Action de Recherches Concertée 99/04-235 (IRES, Université catholique de Louvain) is gratefully acknowledged.     

Why are some people (and countries) more protectionist than others?

We analyze two cross-country data sets that contain information on attitudes toward trade as well as a broad range of socio-demographic and other indicators. We find that pro-trade preferences are significantly and robustly correlated with an individual's level of human capital, in the manner predicted by the factor endowments model. Preferences over trade are also correlated with the trade exposure of the sector in which an individual is employed: individuals in non-traded sectors tend to be the most pro-trade, while individuals in sectors with a revealed comparative disadvantage are the most protectionist. Third, an individual's relative economic status has a very strong positive association with pro-trade attitudes. Finally, non-economic determinants, in the form of values, identities, and attachments, play an important role in explaining the variation in preferences over trade. High degrees of neighborhood attachment and nationalism/patriotism are associated with protectionist tendencies.