In some data envelopment analysis (DEA) applications, some inputs of DMUs have negative values with positive cost. This paper generalizes the global cost Malmquist productivity index to compare the productivity of different DMUs with negative inputs in any two periods of times under variable returns to scale (VRS) technology, and then the generalized index is decomposed to several components. T...

the present study is an attempt towards remodeling cost, revenue and profit relationship within the network process. the previous models of data envelopment analysis (dea) have been too general in their scope and focused on the input and the output within a black box system, therefore they have not been able to measure various phases simultaneously within a network system. by using these models...

An emerging trend in performance evaluation is combining social network analysis methods with data envelopment (DEA) models and using centrality to distinguish DEA results. One study employed an input-oriented variable-returns-to-scale model address referent decision-making units the corresponding lambda values construct a network. This referenced literature improved on use of weight sets We co...

In order to evaluate the performance of socially responsible investment (SRI) funds, we propose some models which use data envelopment analysis and can be computed in all phases of the business cycle. These models focus on the most crucial elements of an investment in mutual funds. In the literature both constant and variable returns to scale DEA models have been used to evaluate the performanc...

The calculation of RTS amounts to measuring a relationship between inputs and outputs in a production structure. There are many methods to measure RTS in the primal space or the dual space. One of the main approaches is using the multiplier on the convexity constraint. But returns to scale measurements in DEA models are affected by the presence of regulatory constraints. These additional constr...

In production theory, it is necessary to be capable of predicting the production func- tion’s long-run behaviors. Hereof, returns to scale is a helpful concept. Returns to scale describes the reaction of a production function to the proportionally scaling all its input variables. In this regard, Data envelopment analysis (DEA) provides a com- prehensive framework for returns to scale evaluation...

The Production Possibility Set (PPS) is defined as the set of all inputs and outputs of a system in which inputs can produce outputs‎. ‎In Data Envelopment Analysis (DEA)‎, ‎it is highly important to identify the defining hyperplanes and especially the strong defining hyperplanes of the empirical PPS‎. ‎Although DEA models can determine the efficiency of a Decision Making Unit (DMU)‎, ‎but they...

introduction: due to increased costs of health sector, much effort has been done to compare the performance of hospitals and measure their efficiency in recent years. the purpose of this study was to evaluate the relative efficiency of public and private hospitals in qom during 2007 using data envelopment analysis (dea) approach. methods: this was an applied and analytic study. the study popula...

objective: the aims of this study were to determine energy efficiency and co2 use pattern of grape production in zanjan province, iran by a non-parametric method of data envelopment analysis (dea). methods: initial data were collected using a face to face questionnaire from 42 orchards in abhar city of zanjan province which is one of the most important centers of grape production in iran. the d...