Socioeconomic predictors of forest use values in the Peruvian Amazon: A potential tool for biodiversity conservation

Conservation is a crisis discipline requiring rapid action with limited funds. This study examines the potential of socioeconomic variables to predict forest use values. If natural resource use can be predicted from socioeconomic data, conservation planners could rapidly identify and focus conservation programs on the sectors of local populations that most intensively utilize local flora and fauna. Families in three communities in the northern Peruvian Amazon were surveyed over a 6-month period. Data were collected on use of flora and fauna from six locally determined use categories (food, medicine and poisons, wood, weavings, adornments, and “other”) in forest types of three age classes (fallow fields—very young forests, young secondary forests, and old secondary forests). Forest use values were the dependant variables calculated in $/ha/year. Socioeconomic variables included: age, education, family size, residence time, land worked, land owned, number of fishing nets, chickens, pigs, cows, and/or mules owned (all proxies for productive assets), and level of ecological knowledge (ability of informants to correctly identify forest species and answer basic questions about their biology). Ordinary least square multiple regressions were run independently for each forest type. Regressions were also run separately for the two most valuable use categories, food and wood. Low R² adjusted values (all < 0.3) reflect the difficulty in predicting human behavior due to confounding variables and complex interactions. Residence time and a household's community of residence were the most significant predictors of forest use values. Households in Vista Alegre, the community with the highest density of people and smallest landholdings per household, extracted the highest value of forest products per hectare. The longer a family stayed in any community the higher the value of forest goods they extracted. If families that lived in an area longest are the most intensive extractors of forest products, they should be a major focus for conservation programming. In addition, the higher value of products extracted from forests by some families may make them more open to strategies seeking to protect long-term viability of the resources they utilize. The importance of residence time also indicates that planners need to account for changes in the resource use patterns of stakeholders over time.     

客户知识的关键维度及其管理过程

客户知识成为企业维持持续竞争优势的关键资源。理解客户知识的内涵和关键维度是企业进行客户知识管理的前提和基础，论文结合不同行业企业的实践经验，提出客户知识应包括四个关键维度：用于客户的知识、来自客户的知识、关于客户的知识和共同创造的知识，并针对每个雏度分析了企业当前运用的管理方法，基于此．界定了客户知识管理的概念，构建了客户知识管理的过程模型，为企业有效进行客户知识管理提供参考。     

Is capital a collusion device?

Summary. We examine how irreversible capital reduces the possibility of a duopoly to sustain implicit collusion by grim strategies, when the product is homogenous and firms compete in quantities. Compared with the case of reversible capital, there are two countervailing effects: Deviation from an existing collusion is less attractive, because capital once installed causes costs forever. But the punishment will also be less severe due to the high capacity the deviating firm can build before punishment starts. The last effect dominates, meaning that the commitment value of capital is negative for all firms. If capital is irreversible, collusion breaks down for realistic magnitudes of interest rates. Received: April 30, 1999; revised version: November 30, 2001     

转基因标签的消费者维度思考

本文从消费者角度分析了现行转基因标签政策实施过程中存在的成本转移、道德风险等等被忽视的问题．并以我国包装大豆色拉油市场为例，利用垂直差别化模型对加贴转基因标签前后消费者经济福利进行了比较。     

Preferences in the Future

Environmental economics has been much occupied with the discount rate, which is the value of future costs and benefits relative to present costsor benefits. But at least as important is the question of whatshould be discounted, that is, what the value of those future environmentalbenefits is to future generations. This paper analyzes the role for futurepreferences and discusses the state of knowledge. I argue that theappropriate discount rate is the market one, and that the real problemis determining future willingness-to-pay. This approach makes clearerthe connection between discounting and the valuation debate.This paper focuses on two features that have been prominent in that debate:existence value and reference dependence. I argue that thereis a vital connection between the two constructs and that this link yieldsimportant implications for future willingness-to-pay.     

Nonresponse in Contingent Valuation-reducing uncertainty in value inference

This paper focuses on problems associated with nonresponse in Contingent Valuation surveys. The results from a telephone follow-up survey show that value inference can be considerably improved by information on nonrespondents' attitudes.     

Economic Valuation of Health for Environmental Policy: Comparing Alternative Approaches. Introduction and Overview

Protecting human health is a primary goal of environmental policy and economic evaluation of health can help policy-makers judge the relative worth of alternative actions. Economists use two distinct approaches in normatively evaluating health. Whereas environmental economists use benefit-cost analysis supported by monetary valuation in terms of willingness-to-pay, health economists evaluate interventions based on cost-effectiveness or cost-utility analysis (CEA), using quality-adjusted life-years (QALY) or similar indexes. This paper provides background on the controversy about the relative merits of these approaches and introduces the remaining papers in the special issue. These papers (with one exception) were presented at a conference sponsored by the Department of Economics at the University of Central Florida with support from the US Environmental Protection Agency. Although CEA might not lead to substantially different implications for environmental policy than benefit-cost analysis, and QALY may provide a benefit transfer tool to fill gaps in the morbidity valuation literature, the papers in this issue raise serious concerns about the suitability of QALY-based CEA for environmental regulatory analysis. QALY does not in general appropriately represent individual preferences for health and CEA is neither independent of income distribution nor adequate to assess efficiency.     

Characterization of a class of moral-hazard, adverse selection games

Studying a principal-agent game in which the agent alone observes the state of the world and reports it, but the moral hazard is not reducible, shows that, if the principal uses all signals, then no solution exists, i.e. there is no contract that elicits truth-telling and motivates the agent to exert effort. When the principal does not use signals on the state of the world that seem irrelevant, a solution exists in which some of the ex post signals on outcome are not used, even though they obey the informativeness condition of Holmstrom (Bell Journal of Economics, 1979, 10, 74–91).     

生态经济学基本问题研究

如何审视生态系统、环境系统与经济系统之间的相互关系,关系到对生态经济学基本问题的科学理解,关系到如何运用科学发展观建设和谐社会、实现经济社会持续发展。本文以此为前提,深入研究生态经济学的基本问题,对生态价值、环境价值、经济价值层次的升级,逻辑上的升华及其内在联系进行了探讨。