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91.
92.
Integrating ecosystem services into conservation assessments: A review   总被引:8,自引:0,他引:8  
A call has been made for conservation planners to include ecosystem services into their assessments of conservation priority areas. The need to develop an integrated approach to meeting different conservation objectives and a shift in focus towards human wellbeing are some of the motivations behind this call. There is currently no widely accepted approach to planning for ecosystem services. This study contributes towards the development of this approach through a review of conservation assessments and the extent to which they include ecosystem services. Of the 476 conservation assessments identified by a set of search terms on the Web of Science, 100 were randomly selected for this review. Of these only seven had included ecosystem services, while another 13 had referred to ecosystem services as a rationale for conservation without including them in the assessment. The majority of assessments were based on biodiversity pattern data while 19 used data on ecological processes. A total of 11 of these 19 assessments used processes, which could be linked to services. Ecosystem services have witnessed an increase in attention received in conservation assessments since the year 2000, however trends were not apparent beyond this date. In order to assess which types of ecosystem services and how they have been accounted for in conservation assessments, we extended our review to include an additional nine conservation assessments which included ecosystem services. The majority included cultural ecosystem services, followed by regulatory, provisioning and supporting services respectively. We conclude with an analysis of the constraints and opportunities for the integration of ecosystem services into conservation assessments and highlight the urgent need for an appropriate framework for planning for ecosystem services.  相似文献   
93.
This paper introduces the idea of “robust political economy.” In the context of political economic systems, “robustness” refers to a political economic arrangement's ability to produce social welfare-enhancing outcomes in the face of deviations from ideal assumptions about individuals' motivations and information. Since standard assumptions about complete and perfect information, instantaneous market adjustment, perfect agent rationality, political actor benevolence, etc., rarely, if ever actually hold, a realistic picture and accurate assessment of the desirability of alternative political economic systems requires an analysis of alternative systems' robustness. The Mises-Hayek critique of socialism forms the foundation for investigations of robustness that relax ideal informational assumptions. The Buchanan-Tullock public choice approach complements this foundation in forming the basis for investigations of robustness that relax ideal motivational assumptions. JEL Code B53, P16, P26  相似文献   
94.
We formally analyze the question of whether a price leader must control a large share of the market. Our main result is that if other producers have rising marginal costs and behave as price takers, even the smallest firm in a competitive industry with a rising supply curve can enhance its profits by cutting output and raising price, becoming a price leader. Therefore, we would expect pure competition to be destroyed under these technological conditions.  相似文献   
95.
Recent policy debate in Europe suggests that a shorter workweek will lead to more jobs (worksharing). We derive and estimate a model where the firm employs two types of workers, some working overtime, the rest standard hours. Worksharing is not always a prediction of the theory. Using German establishment‐level panel data (the IAB‐ESTABLISHMENT panel), 1993–1999, we find no evidence of pro‐worksharing effects except in small plants in the East German non‐service sector. There is evidence that a cut in standard hours lowers the proportion of overtime workers in a plant, as predicted by the theory, and increases the proportion of standard‐time plants.  相似文献   
96.
Abstract  The tables for the Friedman rank-test arc extended using a sampling method. A table is given for the traditional significance levels .01, .025, .05 and .10 for number of blocks equal to 7 and 8 and for treatments of size 6 and 7. A brief discussion of available tables is also included along with an example of an application.  相似文献   
97.
The case is investigated when Hoeffding's one sample U–statistic theorem for the sample variance S2 is not applicable. It is shown that this occurs only when the parent distribution is the two–point distribution with jumps of equal magnitude. For this exceptional case the standardised S2 is shown to converge in distribution to (1 – V )√2, where V has chi–square distribution with one degree of freedom.  相似文献   
98.
In our earlier paper [Srivastava, Agnihotri and Dwivedi (1980)] the dominance of double k-class over k-class with respect to exact mean squared error matrix criteria is established. It is observed that given a member of k-class, one can pick up a member of double k-class that will provide an improved estimator of the coefficients. This result prompted us to study the exact finite sample properties of the double k-class estimator. For this, we have considered a structural equation containing two endogenous variables and have investigated the properties of double k-class estimators of the coefficients of explanatory endogenous variables assuming characterizing scalars to be non-stochastic.  相似文献   
99.
100.
Prof. Dr. T. Royen 《Metrika》1990,37(1):145-154
Summary It is proved that for any fixed argument the sequence (P k) of the distribution functions of the ranges ofk i.i.d. univariate random variables is log-concave if the random variables have a log-concave density. If the support of the distribution is an infinite interval and the density is monotonous then the theorem holds also with “log-convex” instead of “log-concave”. The resulting inequalities can be used by a quick algorithm for closed maximum range test procedures for all pairwise comparisons (Royen 1988, 1989a, 1989b). Under the above assumptions the application of this algorithm can be extended e.g. to pairwise comparisons of variances.  相似文献   
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