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241.
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.  相似文献   
242.
243.
This paper presents a broad diagnostic of the level of institutional development in Portugal in the legal, corporate governance and financial systems. A comparative assessment suggests that Portuguese institutions are less developed than their European Union and East Asian counterparts, more developed than Greek institutions and on a level similar to that of Spanish institutions. We use data for a wide cross-section of countries since 1960 and correlate indicators of institutional development with the long-term average growth rate, identifying issues where reform is likely to significantly affect economic growth. We construct three new indices that measure the potential of institutional reform - the impact of reform on growth, the required reform effort and the efficiency of reform index - by taking into consideration the institutional distance between Portugal and the European Union. These indices measure, respectively, which reforms have the most payoff in terms of growth, which are less costly to undertake and which deliver the most growth per required effort. Our results strongly suggest that in a large number of issues, institutional reform may translate into substantially higher rates of economic growth. Of the ten most promising reforms, six are in the legal area, irrespective of which of the indices is considered. Whereas legal reform is promising at the aggregate and the microeconomic levels, in the financial sector aggregate indicators offer the wider scope for productive reform, while in the corporate governance area it is indices at the micro level that hold the most promise. These results support the view that a comprehensive reform effort is likely to deliver higher rates of growth in Portugal, allowing faster real convergence with the rest of the European Union.Received: January 2003, Accepted: February 2004, JEL Classification: O0, O5, K00, K4, G2, G3This paper is based on Firms, Financial Markets and the Law: Institutions and Economic Growth in Portugal, prepared for the conference Desenvolvimento Económico Português no Espaço Europeu: Determinantes e Políticas, organized by the Banco de Portugal. Financial support by the Banco de Portugal, NOVA FORUM and FUNDAÇÃO Para a Ciência e tecnologia and Polti through feder are gratefully acknowledged. Comments from Marcelo Rebelo de Sousa, two anonymous referees and the editor are sincerely appreciated. The usual disclaimer applies.  相似文献   
244.
The literature on mergers has extensively analyzed the decision to merge by private firms, but it has not considered the decision to merge by private and public firms. We assume that when a private firm and a public firm merge (or when one of them acquires the other), they set up a multiproduct firm in which the government owns an exogenous percentage stake. In this framework, we show that the decision to merge by firms depends on the degree to which goods are substitutes and on the percentage of the shares owned by the government in the multiproduct firm.  相似文献   
245.
246.
Abstract. This paper contributes to the growing literature that analyses the Spanish publishing performance in Economics throughout the 1990s. Several bibliometric indicators are used in order to provide Spanish rankings (of both institutions and individual authors) based on Econlit journals. Further, lists of the ten most influential authors and articles over that period, in terms of citations, are reported. We are grateful to many colleagues who made very useful remarks to preliminary versions of this paper, as well as to two anonymous referees. We are particularly indebted to Xavier Sala-i-Martín, without whose invaluable help this work would not have been possible. All errors or omissions are of our exclusive responsibility.  相似文献   
247.
Noisy chaotic dynamics in commodity markets   总被引:2,自引:1,他引:2  
The nonlinear testing and modeling of economic and financial time series has increased substantially in recent years, enabling us to better understand market and price behavior, risk and the formation of expectations. Such tests have also been applied to commodity market behavior, providing evidence of heteroskedasticity, chaos, long memory, cyclicity, etc. The present evaluation of futures price behavior confirms that the resulting price movements can be random, suggesting noisy chaotic behavior. Prices could thus follow a mean process that is dynamic chaotic, coupled with a variance that follows a GARCH process. Our conclusion is that models of this type could be constructed to assist in forecasting prices in the short run but not over long run time periods.First version received: June 2001/Final version received: March 2003  相似文献   
248.
Altruism and the Economic Values of Environmental and Social Policies   总被引:2,自引:0,他引:2  
Altruism is a type of non-use value which can have different definitions depending on the type of goods entering the utility function of the altruists and their expectations about the contributions of others. The purpose of this paper is to measure the trade-offs between different types of altruist values originating from social and environmental policies. Environmental policies are concerned with reducing health effects from a power plant while social policies involve both the attainment of public facilities for education and leisure and an increase in the income of the affected population. The empirical application utilizes a choice experiment technique which allows for valuation of multiple goods. Health effects are decomposed into the values of the risk of becoming ill, the duration of the episodes and the limitations imposed by illness. Altruist values are elicited from a population that is not affected by pollution. Results show that altruism is significant for policies directed to reducing health effects and improving the income level of the affected population, whereas there is egoism for a policy aimed at improving public facilities in the polluted suburb. The value of altruism is significantly influenced by the expectations of net benefits to be received by the affected population.  相似文献   
249.
This paper presents a dynamic model that determines the optimal number of deer hunting permit sales, subject to the objective of maximizing the discounted economic benefits stream from both the consumptive and nonconsumptive uses of deer. This bioeconomic model integrates economic benefits estimated using the dichotomous choice contingent valuation method with biological growth constraints on deer. Using a hunting zone in California as a case study, the model found that the optimal levels of buck hunting permits sold should change on a rotational basis over time and that the current practice of not selling doe hunting permits for that zone is non optimal.  相似文献   
250.
Even as advances in information theory over the last quarter century have cast increasing doubt on the proposition that firms successfully maximize profits, the objective of profit maximization continues to be an axiomatic feature of the neoclassical theory of the firm. This paper attempts to improve our understanding firms by treating the objective function as an open question. Specifically, an ontogenetic thought experiment is undertaken to address the question of what differentiates production teams from firms by asking why team members would sell their control rights to a principal, thereby transforming the team into a firm. What results is an account of the emergence of the objective of profit seeking. Profit seeking emerges endogenously as a more fit alternative than the objective of value maximization, which is less capable of coping with uncertainty through purposive adaptation.  相似文献   
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