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91.
Data envelopment analysis (DEA) is the most commonly used approach for evaluating healthcare efficiency [B. Hollingsworth, The measurement of efficiency and productivity of health care delivery. Health Economics 17(10) (2008), pp. 1107–1128], but a long-standing concern is that DEA assumes that data are measured without error. This is quite unlikely, and DEA and other efficiency analysis techniques may yield biased efficiency estimates if it is not realized [B.J. Gajewski, R. Lee, M. Bott, U. Piamjariyakul, and R.L. Taunton, On estimating the distribution of data envelopment analysis efficiency scores: an application to nursing homes’ care planning process. Journal of Applied Statistics 36(9) (2009), pp. 933–944; J. Ruggiero, Data envelopment analysis with stochastic data. Journal of the Operational Research Society 55 (2004), pp. 1008–1012]. We propose to address measurement error systematically using a Bayesian method (Bayesian DEA). We will apply Bayesian DEA to data from the National Database of Nursing Quality Indicators® to estimate nursing units’ efficiency. Several external reliability studies inform the posterior distribution of the measurement error on the DEA variables. We will discuss the case of generalizing the approach to situations where an external reliability study is not feasible.  相似文献   
92.
《Statistics》2012,46(6):1396-1436
ABSTRACT

The paper deals with an asymptotic relative efficiency concept for confidence regions of multidimensional parameters that is based on the expected volumes of the confidence regions. Under standard conditions the asymptotic relative efficiencies of confidence regions are seen to be certain powers of the ratio of the limits of the expected volumes. These limits are explicitly derived for confidence regions associated with certain plugin estimators, likelihood ratio tests and Wald tests. Under regularity conditions, the asymptotic relative efficiency of each of these procedures with respect to each one of its competitors is equal to 1. The results are applied to multivariate normal distributions and multinomial distributions in a fairly general setting.  相似文献   
93.
The hazard rate (HR) and mean residual lifetime are two of the most practical and best-known functions in biometry, reliability, statistics and life testing. Recently, the reversed HR function is found to have interesting properties useful in additional areas such as censored data and forensic science. For these three biometric functions, we propose testing methods that they take on a known functional form against that they dominate or are dominated by this known form. This goodness-of-fit-type testing is wider in applications and more interesting than the long-standing testing procedures for exponentiality against the monotonicity of these functions or even the change point problems. This is so since we can test against any choice of the survival distribution and not just exponentiality. For this general testing, we present easy to implement tests and generalize them into classes of statistics that could lead to more powerful and efficient testing.  相似文献   
94.
张虹 《职业时空》2014,(6):82-84
在高职物流专业英语教学中运用工学结合模式,可以把工作过程与教学过程对接,依据典型工作任务和工作过程设计课程体系和内容,实现"教学做"一体化教学,学生在学校就可以学习到企业岗位真正需求的知识和技能,提高物流英语课堂教学的有效性。  相似文献   
95.
We consider a problem of evaluating efficiency of Decision Making Units (DMUs) based on their deterministic performance on multiple consumed inputs and multiple produced outputs. We apply a ratio-based efficiency measure, and account for the Decision Maker׳s preference information representable with linear constraints involving input/output weights. We analyze the set of all feasible weights to answer various robustness concerns by deriving: (1) extreme efficiency scores and (2) extreme efficiency ranks for each DMU, (3) possible and necessary efficiency preference relations for pairs of DMUs, (4) efficiency distribution, (5) efficiency rank acceptability indices, and (6) pairwise efficiency outranking indices. The proposed hybrid approach combines and extends previous results from Ratio-based Efficiency Analysis and the SMAA-D method. The practical managerial implications are derived from the complementary character of accounted perspectives on DMUs׳ efficiencies. We present an innovative open-source software implementing an integrated framework for robustness analysis using a ratio-based efficiency model on the diviz platform. The proposed approach is applied to a real-world problem of evaluating efficiency of Polish airports. We consider four inputs related to the capacities of a terminal, runways, and an apron, and to the airport׳s catchment area, and two outputs concerning passenger traffic and number of aircraft movements. We present how the results can be affected by integrating the weight constraints and eliminating outlier DMUs.  相似文献   
96.
基于多维效应的能源效率评估使人们在达到经济增长目的的同时兼顾能源安全、竞争力、环境、社会和技术的可持续性。论述能源效率内涵演化发展的路径,在此基础上将能源效率的内涵扩展至多维效应。以非参数DEA(Data Envelopment Analysis)方法为例,研究基于多维效应的能源效率评估方法的演化与发展趋势。研究结果显示:采用DEA方法对基于多维效应的能源效率进行评估的发展趋势主要有以下3点:能源效率的内涵不断延伸;DEA模型向非导向非径向模型转变;能源效率评估的研究维度不断扩展。对多维效应的能源效率综合指标评价体系和评价方法还需做深入研究。  相似文献   
97.
提高能源消耗产出效率是新常态下经济发展的必然趋势,随机扰动和外部环境是研究能源消耗产出效率不可回避的问题,而传统的DEA模型无法剔除非期望产出对效率值的影响。本文通过构建四阶段Bootstrap-DEA-Malmquist模型,采用1990~2014年的省际面板数据作为样本数据,通过松弛指标调整能源投入,剔除外部环境和随机因素对能源效率和能源全要素生产率的扰动,并借助Bootstrap随机抽样法进一步减小由于样本差异造成的影响,从静态和动态两个维度测算了中国能源消耗产出效率和全要素生产率。研究发现,外部环境和随机扰动对能源效率的估算具有显著影响,剔除外部环境影响因素后得到的能源效率值、技术效率变化以及全要素生产率变动均有不同程度的下降,而调整初始投入后的技术进步值有所上升。此外,考虑环境因素时,能源效率值下降,但是进一步运用Bootstrap随机抽样法消除随机因素的影响后,能源效率值有所上升。本文的主要贡献在于将环境因素和随机因素从能源效率与能源全要素生产率的测算中剥离,获得更为准确的能源效率值和能源全要素生产率值。  相似文献   
98.
在阐述新国际贸易格局下港口物流发展新特点的基础上,分析国际贸易新格局下港口物流发展模式存在的问题,提出了国际贸易新格局下港口物流发展模式的可行路径:(1)基于港口物流协同机制的港口物流有序竞合战略;(2)基于港口物流信息化运作模式的港口物流供应链整合战略;(3)基于低碳物流模式的港口物流增值服务战略等。  相似文献   
99.
对反腐倡廉建设开展效率评估,不仅有利于改进和提升反腐倡廉的效率,推进反腐倡廉建设科学化的进程,还能为反腐倡廉形势评估开辟一个独特的视角。文章在综述国内反腐倡廉建设评估研究的基础上,提出了反腐倡廉效率评估的必要性;并基于反腐倡廉建设目标与特点分析,论证了数据包络分析方法对反腐倡廉效率评估的适用性;参照学术界已有的成果,结合实践逻辑构建了反腐倡廉效率评估指标体系;阐述了数据包络分析的模型选择及运算过程。  相似文献   
100.
In this paper, proportion estimators and associated variance estimators are proposed for a binary variable with a concomitant variable based on modified ranked set sampling methods, which are extreme ranked set sampling (ERSS), median ranked set sampling (MRSS), percentile ranked set sampling (Per-RSS) and L ranked set sampling (LRSS) methods. The Monte Carlo simulation study is performed to compare the performance of the estimators based on bias, mean squared error, and relative efficiency for different levels of correlation coefficient, set and cycle sizes under normal and log-normal distributions. Moreover, the study is supported with real data application.  相似文献   
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