A non-radial DEA approach to measuring environmental performance

Data envelopment analysis (DEA) has gained great popularity in environmental performance measurement because it can provide a synthetic standardized environmental performance index when pollutants are suitably incorporated into the traditional DEA framework. Past studies about the application of DEA to environmental performance measurement often follow the concept of radial efficiency measures. In this paper, we present a non-radial DEA approach to measuring environmental performance, which consists of a non-radial DEA-based model for multilateral environmental performance comparisons and a non-radial Malmquist environmental performance index for modeling the change of environmental performance over time. A case study of OECD countries using the proposed non-radial DEA approach is also presented. It is found that the environmental performance of OECD countries as a whole has been improved from 1995 to 1997.     

保险系统的损失分布模型

在计算保险费时，我们不仅要知道危险事故发生时索赔费的平均值，而且还必须知道损失费的概率分布．本文从理赔费是损失费的减扣额出发，考虑了减扣额的增减和损失费的升降，给出了损失费的所有可能概率分布，并同时给出平均净保险费的计算公式．     

Dynamic priority allocation via restless bandit marginal productivity indices

This paper surveys recent work by the author on the theoretical and algorithmic aspects of restless bandit indexation as well as on its application to a variety of problems involving the dynamic allocation of priority to multiple stochastic projects. The main aim is to present ideas and methods in an accessible form that can be of use to researchers addressing problems of such a kind. Besides building on the rich literature on bandit problems, our approach draws on ideas from linear programming, economics, and multi-objective optimization. In particular, it was motivated to address issues raised in the seminal work of Whittle (Restless bandits: activity allocation in a changing world. In: Gani J. (ed.) A Celebration of Applied Probability, J. Appl. Probab., vol. 25A, Applied Probability Trust, Sheffield, pp. 287–298, 1988) where he introduced the index for restless bandits that is the starting point of this work. Such an index, along with previously proposed indices and more recent extensions, is shown to be unified through the intuitive concept of “marginal productivity index” (MPI), which measures the marginal productivity of work on a project at each of its states. In a multi-project setting, MPI policies are economically sound, as they dynamically allocate higher priority to those projects where work appears to be currently more productive. Besides being tractable and widely applicable, a growing body of computational evidence indicates that such index policies typically achieve a near-optimal performance and substantially outperform benchmark policies derived from conventional approaches. This invited paper is discussed in the comments available at: , , , , , .     

二维实用下料问题的数学模型及较优解

二维下料问题是2004年首届全国部分高校研究生数学建模竞赛B题.建立了二维下料问题的数学模型,找到了用料451块,下料方式数为37的较优解,并证明了此问题总用料的下界是449块.     

Experimental Study of Stepped Solar Still Integrated with Reflectors and External Condenser

In this article, an experimental study of a modified stepped solar still with internal and external reflectors and an external condenser is presented. A suction fan is connected with the still to withdraw water vapor. A comparison between the modified stepped solar still and the conventional solar still is conducted. It is found that the productivity of the stepped still with a condenser and with both reflectors and a condenser are about 66% and 165% higher than that of the conventional still, respectively. Finally, the cost of 1 L of distillate for the modified stepped solar still and conventional solar still is estimated.     

我国各地区全要素生产率的测定与比较分析

全要素生产率是衡量经济效益的一项重要指标.本文利用生产要素的影子价格作为权重,提出一种计算全要素生产率的方法.用该方法计算了全国各省（直辖市）的全要素生产率,并对计算结果进行了比较分析.     

Efficiency and total quality management in health care organizations: A dynamic frontier approach

This paper analyses hospital performance using Data Envelopment Analysis (DEA) and the Malmquist productivity index. We follow two approaches to quantify movements in productivity: (1) the traditional approach that only considers output and input variables; and (2) a more comprehensive approach that incorporates movements in quality and restricts some achievements, if quality is reduced. On the premise that the indicator for quality (nosocomial infections) is equivalent to a bad output, we explore the characteristics of, and compare the results of, the different technological ways to incorporate quality (good or bad attributes, strong or weak disposability technological assumptions). After discussing the virtues and limitations of the existing possibilities, the paper presents a better formulation that allows the preservation of TQM postulates. The decomposition in the Malmquist productivity index shows an improvement in productivity and a positive technical change, especially when quality is introduced. This paper forms part of a more extensive research work, financed by the Spanish Science and Technology Ministry (ref. SEC2003-047707).     

公共投资对粮食主产区农业生产率增长的驱动效应分析——基于吉林省1989-2006年数据的实证检验

粮食主产区是我国农业发展的重心,而公共投资是推动粮食主产区农业生产率增长最主要的驱动力。因此,本文以吉林省为例运用Malmquist指数模型定量评估粮食主产区的农业生产率,并进一步应用向量误差修正(VEC)模型分析了公共投资与农业生产率之间的长期均衡关系,实证检验了公共投资对农业生产率的驱动效应。     

碳排放对绿色全要素生产率的影响与地区异质效应

采用DEA-Malmquist方法测度绿色全要素生产率,构建1998-2017年中国省际面板数据模型,考察碳排放对绿色全要素生产率的影响,并进一步分析其地区异质效应.结果表明：碳排放与绿色全要素生产率之间存在显著的倒U型关系,即具有先促进后抑制的作用;碳排放对绿色全要素生产率的影响存在显著的地区异质性,其中,在东部和中部地区呈现出显著的促进作用,而对西部地区则存在显著的倒U型关系.     

制造业全要素生产率的地区差异及收敛性研究——基于企业微观数据的实证

本文构建了技术进步内生的生产函数,并根据企业微观面板数据,采用OP模型和收敛模型测算了中国制造业全国层面及区域层面的全要素生产率,并分析了制造业全要素生产率的地区差异和收敛性。结果显示:2002~2011年中国制造业全国层面全要素生产率年均增长2.36%,受金融危机的影响,2008~2011年仅为-2.14%;在地区差异上,东部地区制造业全要素生产率要低于中西部地区;收敛分析显示,全域的全要素生产率既不存在β收敛也不存在σ收敛,但却存在“俱乐部”收敛,即中西部地区和东部地区内部各自收敛;同时,本文的分析还显示,资本增长率和研发投入都对全要素生产率的增长有显著正影响。