Una investigación de la congestión de productos no deseados en el análisis de envolvente de datos

Congestion is one of the most important subjects in Data Envelopment Analysis (DEA) which helps the Decision Maker (DM) to decide about changing the size of units. The estimation of congestion has attractive advantages from different perspectives. For example, the total cost of a partiular DMU, in which the congestion occurs, can be reduced by the decreases in inputs. On the other hand, the output of units can be increased by the recognizing and eliminating the congestion of DMUs and so, the total profit of decision making units can be increased. Hence, the management is eager to know how to recognize and eliminate the congestion of units. Most of the existing methods to estimation of the congestion in the literature consider only the desirable outputs. This study focuses on the evaluation of congestion in the presence of undesirable outputs and proposes an approach to recognize the congestion of units. The method is demonstrated on a numerical example to illustrate the validity of the proposed method.La congestión es uno de los temas más importantes en el análisis envolvente de datos (DEA) que ayuda al responsable de la toma de decisiones (DM) a decidir sobre el cambio de tamaño de las unidades. La estimación de la congestión tiene atractivas ventajas desde diferentes perspectivas. Por ejemplo, el costo total de una DMU en particular, en la que ocurre la congestión, puede reducirse mediante la disminución de los insumos. Por otro lado, la producción de unidades se puede incrementar reconociendo y eliminando la congestión de las DMU y así, se puede incrementar el beneficio total de las unidades de toma de decisiones. Por lo tanto, la gerencia está ansiosa por saber cómo reconocer y eliminar la congestión de unidades. La mayoría de los métodos existentes para estimar la congestión en la literatura consideran solo los resultados deseables. Este estudio se centra en la evaluación de la congestión en presencia de salidas indeseables y propone un enfoque para reconocer la congestión de unidades. El método se demuestra en un ejemplo numérico para ilustrar la validez del método propuesto

Una investigación de la congestión de productos no deseados en el análisis de envolvente de datos

La congestión es uno de los temas más importantes en el análisis envolvente de datos (DEA) que ayuda al responsable de la toma de decisiones (DM) a decidir sobre el cambio de tamaño de las unidades. La estimación de la congestión tiene atractivas ventajas desde diferentes perspectivas. Por ejemplo, el costo total de una DMU en particular, en la que ocurre la congestión, puede reducirse mediante la disminución de los insumos. Por otro lado, la producción de unidades se puede incrementar reconociendo y eliminando la congestión de las DMU y así, se puede incrementar el beneficio total de las unidades de toma de decisiones. Por lo tanto, la gerencia está ansiosa por saber cómo reconocer y eliminar la congestión de unidades. La mayoría de los métodos existentes para estimar la congestión en la literatura consideran solo los resultados deseables. Este estudio se centra en la evaluación de la congestión en presencia de salidas indeseables y propone un enfoque para reconocer la congestión de unidades. El método se demuestra en un ejemplo numérico para ilustrar la validez del método propuesto

A full investigation of the directional congestion in data envelopment analysis

One of interesting subjects in Data Envelopment Analysis (DEA) is estimation of congestion of Decision Making Units (DMUs). Congestion is evidenced when decreases (increases) in some inputs result in increases (decreases) in some outputs without worsening (improving) any other input/output. Most of the existing methods for measuring the congestion of DMUs utilize the traditional definition of congestion and assume that inputs and outputs change with the same proportion. Therefore, the important question that arises is whether congestion will occur or not if the decision maker (DM) increases or decreases the inputs dis-proportionally. This means that, the traditional definition of congestion in DEA may be unable to measure the congestion of units with multiple inputs and outputs. This paper focuses on the directional congestion and proposes methods for recognizing the directional congestion using DEA models. To do this, we consider two different scenarios: (i) just the input direction is available. (ii) none of the input and output directions are available. For each scenario, we propose a method consists in systems of inequalities or linear programming problems for estimation of the directional congestion. The validity of the proposed methods are demonstrated utilizing two numerical examples

Technical efficiency of production in agricultural research: a case study.

We define and model research production at Embrapa, the major Brazilian institution responsible for applied agricultural research in the country. The main theoretical framework we use is data envelopment analysis. We explore the ecoomic interpretation of these models to assess cost and technical efficiencies for the production of agricultural research in Brazil. Efficiency results are then compared with alternative measures defined via a stochastic frontier

Embrapa's evaluation and awards system: selected papers.

This paper presents basic conceptsw and operational aspects of Performance Evaluation system and Premiums fos outstanding resuilts irnplemented by Embrapa in 1996. This system aims to increase performance of research units, research teams and employess in gerenal, rewarding the more productive members of the institution. This system procedure for research units; e) team and individual empoyee evaluation; and, d) team and individual reward procedure. O presente trabalho apresenta conceitos e aspectos operacionais do Sistema de Avaliação e Premiação por Resultados da Embrapa, implantado em 1996. O sistema objetiva elevar o desempenho das unidades de pesquisa, das equipes e empregados da Empresa e recompensar os mais produtivos. O sistema e constituido por 4 componentes: a) avaliação de unidades; b) premiação de unidades; c) Avaliação de equipes e empregados; e d) premiação de equipes e empregados

Novel approaches to performance evaluation and benchmarking for energy-efficient multicast: empirical study of coded packet wireless networks

With the advancement of communication networks, a great number of multicast applications such as multimedia, video and audio communications have emerged. As a result, energy efficient multicast in wireless networks is becoming increasingly important in the field of Information and Communications Technology (ICT). According to the study by Gartner and Environmental Protection Agency (EPA) report presented to United State Congress in 2007,energy consumption of ICT nodes accounts for 3% of the worldwide energy supply and is responsible for 2% of the global Carbon dioxide (CO2) emission. However, several initiatives are being put in place to reduce the energy consumption of the ICT sector in general. A review of related literature reveals that existing approaches to energy efficient multicast are largely evaluated using a single metric and while the single metric is appropriate for effective performance, it is unsuitable for measuring efficiency adequately. This thesis studied existing coded packet methods for energy efficiency in ad hoc wireless networks and investigates efficiency frontier, which is the expected minimum energy within the minimum energy multicast framework. The energy efficiency performance was based on effective evaluation and there was no way an inefficient network could reach a level of being an efficiency frontier. Hence, this work looked at the position of how true efficiency evaluation is obtained when the entire network under examination attains their efficiency frontiers using ratios of weighted outputs to weighted inputs with multiple variables. To address these challenges and assist network operators when formulating their network policies and performing network administrations, this thesis proposed novel approaches that are based on Data Envelopment Analysis (DEA) methodology to appropriately evaluate the efficiency of multicast energy and further minimizes energy transmission in ad hoc wireless networks without affecting the overall network performance. The DEA, which was used to study the relative efficiency and productivity of systems in Economic and Operational Research disciplines, is a non-parametric method that relies on linear programming technique for optimization of discrete units of observation called the decision making units (DMUs)

Greenhouse gas emissions and the productivity growth of electricity generators

This paper analyses electricity generation in four Australian states and the Northern Territory in the late 1990s It finds that productivity growth estimates for electricity generators can change significantly when allowance is made for greenhouse gas emissions. Using an innovative analytical technique for incorporating environmental impacts in productivity estimates, it shows that productivity growth is overestimated when emission intensity is rising and underestimated when emission intensity is falling. This is because emissions are undesirable and so if they fall (grow) per unit of output then this will tend to increase (decrease) estimated productivity.greenhouse gas emissions - productivity growth - electricity - abatement

Pay for performance in health care: a new best practice tariff-based tool using a log-linear piecewise frontier function and a dual–primal approach for unique solutions

Health care systems worldwide have faced a problem of resources scarcity that, in turn, should be allocated to the health care providers according to the corresponding population needs. Such an allocation should be as much as effective and efficient as possible to guarantee the sustainability of those systems. One alternative to reach that goal is through (prospective) payments due to the providers for their clinical procedures. The way that such payments are computed is frequently unknown and arguably far from being optimal. For instance, in Portugal, public hospitals are clustered based on criteria related to size, consumed resources, and volume of medical acts, and payments associated with the inpatient services are equal to the smallest unitary cost within each cluster. First, there is no reason to impose a single benchmark for each inefficient hospital. Second, this approach disregards dimen sions like quality (and access) and the environment, which are paramount for fair comparisons and benchmarking exercises. This paper proposes an innovative tool to achieve best-practices tariff. This tool merges both quality and financial sustain ability concepts, attributing a hospital-specific tariff that can be different from hospital to hospital. That payment results from the combination of costs related to a set of potential benchmarks, keeping quality as high as possible and higher than a user-predefined threshold, and being able to generate considerable cost savings. To obtain those coefficients we propose and detail a log-linear piecewise frontier function as well as a dual–primal approach for unique solutions.info:eu-repo/semantics/publishedVersio