Measuring Carbon- Environmental Efficiency with Imprecise Data by Using Fuzzy Data Envelopment Analysis (Case Study: Iran and Oil-Rich Countries)

Data Envelopment Analysis (DEA) is a powerful technique for measuring efficiency. The traditional DEA approach is applicable when inputs and outputs are certain. Since, some input and output data, such as CO2 emission are often imprecise or vague in real world, this approach cannot be used efficiently. Therefore, this study uses the fuzzy data envelopment analysis to measure carbon-environmental efficiency. The results show that the average interval carbon-environmental efficiency is 75.90 percent in the sample and period under study. In addition, the minimum and maximum carbon- environmental efficiency scores in Iran are 61 and 74 percent, respectively, which indicates low environmental efficiency in Iran compared to other countries.  Accordingly, using inputs optimally and lowering dependency on resources are recommended for increasing the carbon-environmental efficiency.