Data envelopment analysis model and its application on technical efficiency evaluation of coal enterprise

A math model based on Data Envelopment Analysis was proposed to make comprehensive technical efficiency evaluation for coal enterprise with multi-input and multi-output systems generally, and this makes it complex and difficult to make precise technical efficiency evaluation, for example, it is hard to set evaluating weights index and difficult to get sound evaluation when the evaluation function is unknown. However, these difficulties can be avoided with DEA model. The C
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GS
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model and EC
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GS
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model derived from C
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GS
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model were proposed and their efficiency judgment criterions were given in this paper. Then based on existing data, the model was applied to make technical efficiency evaluation for Chinese coal enterprises to estimate their technical performance.