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71.
Container terminal production is both an important and complicated element in the contemporary global economy. This paper aims to evaluate the efficiency of the world’s most important container ports and terminals using the two alternative techniques of Data Envelopment Analysis (DEA) and the Free Disposal Hull (FDH) model. The results give an insight into the current efficiency ranking of the world’s major container ports and terminals. They also confirm expectations that the available mathematical programming methodologies lead to different results and that appropriate variable definition of input and output factors is a crucial element in meaningful applications of DEA and FDH. It is also concluded that the availability of panel data, rather than cross-sectional data would greatly improve the validity of the efficiency estimates derived from all the mathematical programming techniques applied.JEL Classification:C61, D24, E23, L23, L25, L92  相似文献   
72.
高连续性路径空间是步行健身行为高效性与安全性 的重要保障。当前城市建设中,能够被大众高效利用的健身 步道呈碎片化分布,全民健身导向下亟须在现有城市空间中 进行高连续性的步道网络化构建。以青岛主城四区为例,基 于连续性目标,通过对OSM数据的爬取与处理,形成适于连 续度赋值的城市基础路网数据。挖掘具有高连续性特征的铁 路沿线、高架走廊、滨河沿海、环景观外边界路径等潜力空 间融入步道选线设计,提出与地铁站点相结合的高连续性选 线技术路线。基于ArcGIS网络分析计算成本最小路径,兼顾 路口等级及公园、绿地、湖泊等自然资源的紧邻性进行步道 选线规划,并从连续度水平、便捷可达性、环境舒适性、空 间多元性几方面对选线结果进行探讨。该选线途径有助于提 升城市步行运动环境的健身利用效能,为实现高连续性的健 身步道网络构建提供设计支持。  相似文献   
73.
基于ESDA-GWR的粮食单产及其驱动因子的空间异质性研究   总被引:13,自引:0,他引:13  
在耕地面积扩展有限和城市化高速发展的背景下,粮食单产的区域差异对我国粮食安全具有重要意义。以我国31省(市、自治区)为研究单元,借助ESDA和GWR模型,结合我国各地自然条件的差异及其经济发展类型,揭示我国粮食单产的区域差异及其驱动因子的空间异质性。结果表明:1999—2008年,中西部地区粮食单产的增产对全国粮食产量的贡献越来越显著,75%的粮食单产增长潜力较大的区域集中在中西部;粮食单产存在着显著的空间相关性,各省域粮食生产重心发生移动,由传统的"东部为主"逐渐"北上西进",向中西部地区欠发达省份集中;不同区域粮食单产的驱动因素呈现为一种非均衡联动的局域性特征,化肥施用量对粮食单产的影响在两个时间断面中差异最大,1999年回归系数全为正值,而在2006—2008年出现负值,这表明部分地区化肥对粮食单产的边际效应已经达到递减阶段。因此,应结合我国不同区域当前粮食单产的现状和驱动因子的效应机理,积极采取相应的有效措施以保障我国的粮食安全。  相似文献   
74.
本文运用33家上市公司面板数据和DEA方法的改进模型,从投入产出结合角度对我国2000-2004年间钢铁、汽车、房地产三大行业的运行效率进行实证研究,建立了运行效率评价模型(G0)及相应投影模型和评价指标体系;计算模型,求出各行业样本公司每年的运行效率指数、投影数据并推算出行业运行效率指数等其他相关数据,定量分析5年间三大行业运行效率的变化趋势,并进行比较研究,得出与事实相吻合的七个结论。  相似文献   
75.
The NSW Government is implementing a financial framework which is designed to encourage government service providers to become more efficient and effective. NSW Treasury is using Data Envelopment Analysis (DEA) to measure the efficiency of major government service providers, such as police, courts and hospitals. This paper outlines the progress in implementing the new financial framework and illustrates the way NSW Treasury will use DEA to help improve the efficiency of government service providers by describing an analysis of the NSW Police Service. The results suggest that NSW police patrols (local police districts) could, on average, reduce input usage by 13.5 percent through better management, and by 6 percent if the patrols could be restructured to achieve the optimal scale. Results also indicate that differences in operating environments, such as location and socioeconomic factors, do not have a significant influence upon the efficiency of police patrols.  相似文献   
76.
A common procedure in economics is to estimate long-run effects from models with lagged dependent variables. For example, macro panel studies frequently are concerned with estimating the long-run impacts of fiscal policy, international aid, or foreign investment.Our analysis points out the hazards of this practice. We use Monte Carlo experiments to demonstrate that estimating long-run impacts from dynamic models produces unreliable results.Biases can be substantial, sample ranges very wide, and hypothesis tests can be rendered useless in realistic data environments. There are three reasons for this poor performance. First, OLS estimates of the coefficient of a lagged dependent variable are downwardly biased in finite samples. Second, small biases in the estimate of the lagged, dependent variable coefficient are magnified in the calculation of long-run effects. And third, and perhaps most importantly, the statistical distribution associated with estimates of the LRP is complicated, heavy-tailed, and difficult to use for hypothesis testing. While many of the underlying problems have been long-known in the literature, the continued widespread use of the associated empirical procedures suggests that researchers are unaware of the extent and severity of the estimation problems. This study aims to illustrate their practical importance for applied research.  相似文献   
77.

This is a study of the effects of R&D spillovers on the cost and production structures of Finnish manufacturing firms. Confidential data on firms is used to estimate a translog cost function system with random coefficients. Although the results suggest that intra-industry spillovers are present in Finnish manufacturing, the findings regarding inter-industry spillovers are inconclusive. The variable cost reduction associated with spillovers is positive, but relatively low. Spillovers reduce the demand for labor but increase the demand for materials. Spillovers also reduce the willingness to pay for capital inputs.  相似文献   
78.

The innovation performance of firms is primarily determined by their own innovative activities and the interaction with their innovation-related environment. This environment typically differs among countries. We assess empirically these differences on firms' innovation performance. To that end we first estimate the relationship between an aggregate innovation input measure and an aggregate innovation output measure, thereby explicitly controlling for structural differences between countries. We then consider the extent to which firms located in a particular country perform better or worse than this estimated benchmark performance. The analysis is based on a panel dataset that we have constructed from Eurostat's first and second Community Innovation Survey. In order to control for possible data contamination we employ an outlier-robust estimator. It appears that among the fourteen countries considered Italy, Germany and Ireland offer an environment that facilitates most the transformation of innovation-related inputs into commercial outputs while the environment in Denmark is the least facilitating.  相似文献   
79.
Most research on technology roadmapping has focused on its practical applications and the development of methods to enhance its operational process. Thus, despite a demand for well-supported, systematic information, little attention has been paid to how/which information can be utilised in technology roadmapping. Therefore, this paper aims at proposing a methodology to structure technological information in order to facilitate the process. To this end, eight methods are suggested to provide useful information for technology roadmapping: summary, information extraction, clustering, mapping, navigation, linking, indicators and comparison. This research identifies the characteristics of significant data that can potentially be used in roadmapping, and presents an approach to extracting important information from such raw data through various data mining techniques including text mining, multi-dimensional scaling and K-means clustering. In addition, this paper explains how this approach can be applied in each step of roadmapping. The proposed approach is applied to develop a roadmap of radio-frequency identification (RFID) technology to illustrate the process practically.  相似文献   
80.
The main purpose of this paper is to analyse the relationship between firm size and innovation activity using Spanish data at firm level corresponding to the manufacturing sector for the period 1990-93. This exercise is different to previous applications because we allow for different size effects in the decision to innovate and the innovation count equation, in the context of a double-hurdle approach. Several tests confirm the hurdle negbin model. We find that firm size is a relevant factor, although size effects are different in both decisions. A robust result from the different specifications estimated is the rejection of the Gilbert and Newbery hypotheses. We find out that the behaviour of firm size is neither linear in the decision nor in thc count equation. We also provide additional, and sometimes different, evidence to previous Spanish studies on R&D.  相似文献   
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