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951.
黄河水市场的建立与水资源的优化配置   总被引:6,自引:0,他引:6  
1987年国务院批准了黄河可供水理分配方案,1994年黄河水利委员会又向沿黄省(区)颁发了《取水许可证》。随着流域社会经济的发展,黄河水资源供需矛盾愈加突出。目前黄河水资源管理调度体制还存在政府指令配水严重失控、没有引入激励补偿机制、同比例丰增枯减的原则不利于水资源优化配置等问题。在黄河上建立水市场符合市场经济规律,可以促进节水,提高水资源的利用率,改善生态环境,有利于水资源的高效配置和合理利用。  相似文献   
952.
We examine the determinants of establishment performance in the UK, using cross‐sectional data from the 1998 Workplace Employee Relations Survey to replicate research by Fernie and Metcalf (1995) who used data from the 1990 Workplace Employee Relations Survey; specifically, we test whether employee representation, contingent pay and efforts to boost employee participation affect a set of economic and industrial relations outcome indicators in the manner they suggest. We also re‐estimate the influential WERS90‐based study of Machin and Stewart (1996) on the links between union status and financial performance. In both cases we report very different results.  相似文献   
953.
The author's observations and studies of safety of navigation locks are described. A mathematical model of lock reliability and its graphical interpretation are presented. The possibility of determination of the accident risk level by processing statistical data is discussed.  相似文献   
954.
数值地形图的生成及其水文地貌特征评价   总被引:17,自引:2,他引:15  
数值地形图(DEM)是利用地理信息系统(GIS)进行流域水文模拟的基础, 其精度直接影响模拟结果在没有现成的数值地形图时, 应用人员往往利用传统的地形图来生成它. 本文分别采用Arc/Info地理信息系统软件提供的哈奇逊法和不规则三角网五次插值法, 对一个实验流域的高程取样点进行插值, 生成了4种不同的数值地形图, 从凹洼分布、流域界定、河网提取、地面坡度和地形指数、以及地面径流汇成等方面, 对它们的水文地貌精度进行了比较. 结果表明, 两种方法都能生成由高程点群所反映的地形, 然而由于哈奇逊法能够结合流域的河网结构及其具有物理基础的水文地貌加强法来处理凹洼问题, 因此大大地提高了其所生成的流域数值地形图水文地貌特征精度.  相似文献   
955.
Cost of equity estimates are compared for three pricing models: the traditional local CAPM, the single (market) factor global CAPM, and the two‐factor global CAPM, with both market and currency index factors. For 2989 US stocks, the average difference in the cost of equity estimates is about 48 basis points between the local CAPM and the single‐factor global CAPM, and is about 61 basis points between the two global models. For 70 developed‐market ADRs, the corresponding average differences are 76 and 47 basis points, respectively. For 48 emerging‐market ADRs, the corresponding average differences are 57 and 70 basis points.  相似文献   
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958.
An aggregate analysis of supply response in the paddy (rice) sector of Sri Lanka during 1952-87 is conducted to identify the impact of pricing policy, irrigation programmes, institutional credit and concessional sales on area, yield and overall supply. The focus of the estimation procedure is the selection of an appropriate functional form for regressions and on the price variable that best represents the price to which producers respond in making area and yield decisions. In the case of both area and yield, the econometric criteria favour the acceptance of log-linear equations with the ratio of the guaranteed price of paddy to fertiliser price. On the basis of overall supply elasticity estimates, it is concluded that while pricing policy, irrigation programmes and institutional credit provide incentives to the expansion of paddy production, concessional sales of rice act as a disincentive.  相似文献   
959.
The time-series distributed lag techniques of econometrics can be usefully applied to cross-sectional, spatial and cross-section time-series situations. The application is perfectly natural in cross-section, time-series models when regression coefficients evolve systematically as the cross-section grouping variable changes. The evolution of such coefficients lends itself to polynomial approximation or more general smoothing restrictions. These ideas are not new, Gersovitz and McKinnon (1978) and Trivedi and Lee (1981) providing two of the earliest applications of cross-equation smoothing techniques. However, their applications were in the context of coefficient variation due to seasonal changes and this may account for the non-diffusion of these techniques. The approach here is illustrated in the context of age-specific household formation equations based on census data, using Almon polynomials when the regression coefficients vary systematically by age group. A second application is provided, using spatial data, explaining the incidence of crime, by region; using polynomial and geometric smoothing to model distance declining regional effects.  相似文献   
960.
This article assesses Canadian banks' ability to realize scale economies and cost complementarities in joint production. The Canadian banking system, with its 10 or so large banks and 50 smaller ones, offers a good database for a study of efficiency, especially since previous work suggests that the system's concentration has had little impact on system competitiveness. This article estimates a system of cost and cost share equations using Zellner's iterative seemingly unrelated regression technique, then evaluates scale economies and cost complementarities from the estimated cost functions' first and second partial derivatives. The article compares a model that classifies deposits as inputs with another that classifies them as outputs. The empirical findings indicate that deposits are better modelled as outputs than inputs; that Canadian banks organize to exhaust available sources of scale economies and economies in joint production; and that conclusions regarding scale economies and cost complementarities differ importantly according to whether deposits are modelled as inputs or as outputs.  相似文献   
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