In data envelopment analysis, there are several methods for measuring efficiency change over time, e.g. the window analysis and the Malmquist index. However, they usually neglect carry-over activities between consecutive two terms. These carry-overs play an important role in measuring the efficiency of decision making units in each term as well as over the whole terms based on the long-term vie...

The level of sustainable development can be measured by eco-efficiency, which is a combination of economic and ecological performance. Utilizing the weighted sum of the improved proportions of the indicators as the objective function, this paper develops a proportional slacks-based measure model to assess eco-efficiency, in which the conventional inputs, and desirable and undesirable outputs ar...

Traditional DEA models deal with measurements of relative efficiency of DMUs regarding multiple-inputs vs. multiple-outputs. One of the drawbacks of these models is the neglect of intermediate products or linking activities. After pointing out needs for inclusion of them in DEA models, we propose a slacks-based network DEA model that can deal with intermediate products. Using this model we can ...