This paper aims to measure the eco-efficiency of Brazilian energy companies in the period 2012-2017. Eco-efficiency is an indicator that reflects the maximization of economic returns and minimization of environmental impacts. The models that will be used are the classical data envelopment analysis (DEA) and the directional distance function (DDF) which has some advantages when including undesirable variables in efficiency calculations. The comparison between the results of the two models allows a comparative evaluation of the eco-efficiency of companies of the electric sector, combining desirable and undesirable outputs and shows that several companies have experienced significant changes in their efficiency scores as well as in their rankings considering the undesirable output. This indicates the importance of including the number of emissions as representative of the undesirable result in the calculation of the sustainable performance of the companies analyzed.

中文翻译：

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使用 DEA 和方向距离函数衡量巴西能源公司的生态效率


本文旨在衡量 2012-2017 年期间巴西能源公司的生态效率。生态效率是反映经济回报最大化和环境影响最小化的指标。将使用的模型是经典的数据包络分析（DEA）和方向距离函数（DDF），其在效率计算中包含不需要的变量时具有一些优势。两个模型结果之间的比较可以对电力行业公司的生态效率进行比较评估，结合理想和不良的产出，并表明，考虑到一些公司的效率得分以及排名发生了重大变化不需要的输出。这表明在计算所分析公司的可持续绩效时将代表不良结果的排放量纳入其中的重要性。