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231.
232.
Valuing ecosystem services: A shadow price for net primary production   总被引:4,自引:0,他引:4  
We analyze the contribution of ecosystem services to GDP and use this contribution to calculate an empirical price for ecosystem services. Net primary production is used as a proxy for ecosystem services and, along with capital and labor, is used to estimate a Cobb Douglas production function from an international panel. A positive output elasticity for net primary production probably measures both marketed and nonmarketed contributions of ecosystems services. The production function is used to calculate the marginal product of net primary production, which is the shadow price for ecosystem services. The shadow price generally is greatest for developed nations, which have larger technical scalars and use less net primary production per unit output. The rate of technical substitution indicates that the quantity of capital needed to replace a unit of net primary production tends to increase with economic development, and this rate of replacement may ultimately constrain economic growth.  相似文献   
233.
In this paper, forecasting models for the monthly outgoing telephone calls in a University Campus are presented. The data have been separated in the categories of international and national calls as well as calls to mobile phones. The total number of calls has also been analyzed. Three different methods, namely the Seasonal Decomposition, Exponential Smoothing Method and SARIMA Method, have been used. Forecasts with 95% confidence intervals were calculated for each method and compared with the actual data. The outcome of this work can be used to predict future demands for the telecommunications network of the University.  相似文献   
234.
This paper presents labor supply functions estimated on a sample of prime age Swedish males. The model used takes account of the nonlinear character of individuals' budget sets caused by the progressive income tax. It also allows preferences to vary between individuals. Calculations with the estimated functions, using a partial equilibrium framework, indicate a sizeable effect of the income tax on hours of work. The average expected deadweight loss of the income tax is found to be approximately 20 percent of tax revenue.  相似文献   
235.
236.
Since 1978 the Federal government has regulated the fuel economy of new cars sold in the United States. The purpose of Corporate Average Fuel Economy (CAFE) standards is to lessen the national dependence on foreign oil. Through the use of theoretical and empirical models this paper examines the impact of CAFE standards on the automobile industry and on energy consumption. It is shown that CAFE standards may or may not save energy. If CAFE does save energy, it does so at a prohibitive cost to the economy. CAFE standards are also shown to have a number of perverse impacts on the automobile industry as well as consumers.  相似文献   
237.
This paper is directed at the following question: given an incomplete set of price data relating to goods or services in some category of output for each of a number of different countries, what arithmetic should be performed on the prices to get a meaningful representation of the relative category price-levels of the countries? In the course of developing an answer to the question, some broader matters are considered and illuminated. A comparison of category price-levels for different countries is analogous to a commonly-encountered problem in many areas, that of ranking ordinally or cardinally in one dimension a group of “entities”—persons, households, firms, industries, etc.—on the basis of sets of measurements associated with the individual entities. It is this point of view which dominates the following presentation.  相似文献   
238.
239.
Here we propose a few estimators of θ, in addition to those studied in Goria (1978), the point of discontinuity of the probability density $$f(x,\theta ) = \frac{1}{{2\Gamma (\alpha )}}e^{ - |x - \theta |} |x - \theta |^{\alpha - 1} ,$$ for $$0< \alpha< 1, - \infty< x< \infty , - \infty< \theta< \infty .$$ We establish the consistency and the optimality of the Bayes and the maximum probability estimators. Despite their nice properties, these estimators are not easy to compute in this case and their effective computation depends on the knowledge of the exponent α. Hence, we propose another class of estimators, dependent upon the spacings of the observations, computable without actual knowledge of the value of α as long as it is known that α < α0 < 1: we show that these estimators converge at the best possible rate. We further demonstrate, using a modified version of the maximum probability estimator's technique, that the tails of the density do not substantially effect their efficiency. Finally a bivariate family of densities, having a ridge dependent on the parameter θ, is considered and it is shown that this family exhibits features similar to the univariate case, and thus, the necessary modifications of the arguments of the univariate case are utilized for the estimation of θ in this bivariate example.  相似文献   
240.
I develop three measures of structural change on the basis of U.S. data: changes in occupational composition, changes in input–output technical coefficients, and changes in capital coefficients. Using pooled cross-section, time-series data for 44 industries over the period from 1970 to 1990, I find that computer investment per worker has had a positive and significant effect on the degree of occupational change and changes in input and capital coefficients.  相似文献   
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