A metafrontier directional distance function approach to assessing eco-efficiency

This paper uses directional distance functions to extend the non-parametric metafrontier approach to efficiency measurement proposed by O’Donnell et al. (Empir Econ 34:231–255, 2008) to the assessment of technological differences in eco-efficiency between groups of producers. Furthermore, eco-efficiency is assessed at the level of specific environmental pressure management. This methodology is applied to a sample of Spanish olive producers that belong to both traditional mountain and traditional plain growing systems. We find great potential for both olive growing systems to reduce environmental pressures. In terms of pressures on natural resources, the most eco-efficient technology is the traditional plain system, while the traditional mountain system is the most eco-efficient when considering pressures on biodiversity. These results might help policymakers design strategies to improve the performance of olive growing and meet the demands of society regarding the economic and ecological functions of this farming activity.     

Meaningful Measures: Indicators on Progress, Progress on Indicators

This article reviews the international debate on statistical indicators. It describes historical backgrounds, as well as the present chaotic situation. It discusses what statistical indicators are and what they are for, as well as criteria for the choice of indicators, designed to monitor the achievement of economic, social, demographic, environmental and other goals set by United Nations conferences. Some suggestions for future work are made.     

浅谈双壁波纹管排水管道工程的质量控制要点

文章从排水管道工程施工的整个流程,包括管材、装运、测量放线、沟槽开挖、管道基础、安管、接口、检查井闭水试验、回填土等质量控制步骤,对排水管道工程施工中常见的一些质量问题进行了分析,并有针对性地提出了相应的质量控制措施。     

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.     

US deficit sustainability revisited: a multiple structural change approach

In this article we re-examine the long-run sustainability of US budget deficits, using Bai and Perron's multiple structural change approach. While the deficit would have been weakly sustainable over the full sample (1947:1–2005:3), strong sustainability would appear only between January 1982 and February 1996.     

Multiplicity in general financial equilibrium with portfolio constraints

This paper explores the role of portfolio constraints in generating multiplicity of equilibrium. We present a simple financial market economy with two goods and two households, households who face constraints on their ability to take unbounded positions in risky stocks. Absent such constraints, equilibrium allocation is unique and is Pareto efficient. With one portfolio constraint in place, the efficient equilibrium is still possible; however, additional inefficient equilibria in which the constraint is binding may emerge. We show further that with portfolio constraints cum incomplete markets, there may be a continuum of equilibria; adding incomplete markets may lead to real indeterminacy.