A new slacks-based measure of Malmquist–Luenberger index in the presence of undesirable outputs

In the majority of production processes, noticeable amounts of bad byproducts or bad outputs are produced. The negative effects of the bad outputs on efficiency cannot be handled by the standard Malmquist index to measure productivity change over time. Toward this end, the Malmquist–Luenberger index (MLI) has been introduced, when undesirable outputs are present. In this paper, we introduce a Data Envelopment Analysis (DEA) model as well as an algorithm, which can successfully eliminate a common infeasibility problem encountered in MLI mixed period problems. This model incorporates the best endogenous direction amongst all other possible directions to increase desirable output and decrease the undesirable outputs at the same time. A simple example used to illustrate the new algorithm and a real application of steam power plants is used to show the applicability of the proposed model.     

嵌入与反嵌：社会工作教育力量参与农村精准扶贫

党的十九大报告强调坚决打赢脱贫攻坚战，并号召各方力量积极参与，社会工作教育力量作为一种专业力量，应积极参与农村精准扶贫。社会工作教育力量在参与农村精准扶贫的过程中，受推动嵌入与阻碍嵌入两种力量的影响。推动嵌入的力量主要包括国家关于社会工作参与扶贫的宏观政策、社会工作项目的需求、专业自身的要求；阻碍社会工作嵌入的力量（反嵌）主要包括进入路径带来的局限、预估与计划制定的妥协、服务过程中对专业的困惑，以及结案中对各种因素的权衡。社会工作教育力量参与农村精准扶贫就是嵌入与反嵌两种力量相互作用的过程。当前，国内社会工作是在嵌入与反嵌过程中由多方力量角力所形成的一种建构过程，折射了社会工作发展的本土化进程。     

大数据应用的质量控制

数据作为重要的数据资源存在，不论是其内在蕴含的信息价值还是其已经成为人类社会所需数据有机组成的客观事实，都迫使我们去不断加强对大数据的应用。然而，由于大数据作为信息技术应用的副产品，其复杂性、不确定性和涌现性决定了我们应用大数据并非易事，存在着很多质量上的问题，除了具有传统数据所有的质量问题外，还包括一些独特的新问题。为了更好地应用大数据，本文对如何进行大数据应用的质量控制进行了初步的研究。主要内容包括以下三个方面：一是对什么是大数据质量、受哪些因素影响、可能存在哪些质量问题进行了探讨；二是从做好理论准备、建立质量控制方案、重视对小数据研究、加强大数据管理、加强大数据人才培养和加强大数据法制建设六个方面，提出了大数据应用的质量控制的基本想法；三是对大数据应用中需要引起注意的几个方面进行了讨论，并结合例子进行了阐释。     

“仿句”的心理基础及其特点探析

仿句是仿拟辞格中的一个小类。仿句是根据所要表达的语意内容,依照人们熟知的语句偶发而仿造出一个新语句。从普通心理学来看,其心理基础可分为两个方面:即从接受角度看,接受者的心理活动是"注意""记忆"和"联想";从生成角度看,仿造者的心理活动为"记忆""联想"和"类推"。仿句有四大特点,即文化的传承、形式的类推、语意的申发和表达的谐趣。     

Data envelopment analysis: Prior to choosing a model

In this paper, we address several issues related to the use of data envelopment analysis (DEA). These issues include model orientation, input and output selection/definition, the use of mixed and raw data, and the number of inputs and outputs to use versus the number of decision making units (DMUs). We believe that within the DEA community, researchers, practitioners, and reviewers may have concerns and, in many cases, incorrect views about these issues. Some of the concerns stem from what is perceived as being the purpose of the DEA exercise. While the DEA frontier can rightly be viewed as a production frontier, it must be remembered that ultimately DEA is a method for performance evaluation and benchmarking against best-practice. DEA can be viewed as a tool for multiple-criteria evaluation problems where DMUs are alternatives and each DMU is represented by its performance in multiple criteria which are coined/classified as DEA inputs and outputs. The purpose of this paper is to offer some clarification and direction on these matters.     

Mental Health Needs and Supportive Services for Elderly and Disabled Residents

Abstract

This study longitudinally assesses the impact that the provision of supportive services has on the mental well-being of the elderly and disabled population living in independent housing developments. The results indicate that the use of supportive services by the mentally ill allowed them to overcome initial lower functional status and achieve a level of mental functioning virtually similar to that of the total resident population. Thus, it is argued that independent living facilities with supportive services can certainly be a successful and cost effective model for a number of frail elderly and mentally ill residents.     

Ethnic segregation of friendship networks in school: Testing a rational-choice argument of differences in ethnic homophily between classroom- and grade-level networks

Adolescents’ school-based friendship networks tend to be segregated along ethnic lines. But few studies have examined whether variation in network boundaries affects the degree of ethnic friendship segregation. We use rational-choice theory to argue that ethnic homophily is more pronounced for friendships between classrooms than for those within classrooms. We empirically test this hypothesis using two-wave German panel data (N = 1258) and stochastic actor-oriented models (RSiena). In line with our theoretical argument, we find that the tendency to form same-ethnic friendships is indeed stronger at the grade level, which translates into stronger ethnic segregation in friendship networks at the grade level than at the classroom level. Implications for research on ethnic segregation in school-based friendship networks are discussed.     

Economic efficiency when prices are not fixed: disentangling quantity and price efficiency

This paper proposes an approach to compute cost efficiency in contexts where units can adjust input quantities and to some degree prices so that through their joint determination they can minimise the aggregate cost of the outputs they secure. The model developed is based on the data envelopment analysis (DEA) framework and can accommodate situations where the degree of influence over prices ranges from minimal to considerable. When units cannot influence prices at all the model proposed reduces to the standard cost efficiency DEA model for the case where prices are taken as exogenous. In addition to the cost efficiency model, we introduce an additive decomposition of potential cost savings into a quantity and a price component, based on Bennet indicators.     

On the need for reform of the Portuguese judicial system – Does Data Envelopment Analysis assessment support it?

The Portuguese judicial system has attracted considerable criticism in recent years and demands for reforms have gained prominence. By using the Data Envelopment Analysis technique and focusing on the performance of 223 Portuguese first instance courts during the period of 2007–2011, this research has found evidence that supports some of this criticism and justifies the calls for reforms, better performance and accountability of the judicial system. In particular, our results found a sector with considerable scope for improvement with less than 16% of the 223 courts analysed making an efficient use of their resources in each year and with only one third of the courts being considered efficient in at least one of the five years assessed. Whilst the results suggest that improvement can be achieved with better case management, scale factors also seem to play an important role in explaining inefficiency, with most of the inefficient courts being smaller than optimal and with smaller courts being, on average, less efficient than larger ones. The existence of a statistically significant relationship between courts׳ efficiency and size was confirmed by the Mann–Whitney test. These results indicate considerable scope for improvement and that some of the planned reforms are timely and seem well targeted. However, the results also suggest that efficiency increases matching peers׳ best practices are not enough to sustainably reduce the prevailing judicial backlog and length of court proceedings in a considerable number of courts. Major changes in the capacity and/or functioning of the Portuguese judicial system might also be required.     

Sensitivity analysis for variance parameters in Bayesian simplex mixed models for proportional data

In this article, we present a Bayesian modeling for response variables restricted to the interval (0, 1), such as proportions and rates, using the simplex distribution for cases in which data have a longitudinal form, taking random effects into account. In order to investigate the stability of posterior distribution, we study through sensitivity analysis, the effect of three different uniparametric prior distributions for variance parameters of random effect on the final estimation. For this purpose, we consider homogeneous and heterogeneous structures for parameters in location and dispersion submodels. Models and results are illustrated with simulated and real data application.