Measuring the Efficiency and Productivity of Cement Companies in Tehran Stock Exchange by Data Envelopment Analysis and Malmquist Productivity Index in Gray Environment

In this study, in order to measure the efficiency and productivity of companies in the cement industry of the Tehran Stock Exchange, the gray data envelopment analysis approach and the Malmquist productivity index have been used.

 For this purpose, in the first step, we identify the appropriate financial ratios for measuring efficiency, then we calculate these ratios for each financial year in the form of gray numbers (intervals). In the next step, these ratios are divided into two groups of input variables and output variables under the title of research variables. Finally, the efficiency and productivity of the studied companies for the two fiscal years 2018 and 2019 by CCR and BCC models. Its components have been estimated.

The results of this study provide a suitable framework for using uncertain information (gray) to replace definite information and thus allow more realistic results to be estimated about the performance of companies.

Originality/Value:

This study uses the Malmquist Gray Productivity Index to provide a framework for comparing productivity changes over time. This index measures the ratio of the measured efficiencies of a production unit in two different time periods.