The relationship between some habitat factors and fish assemblage was analyzed in the Taleghan River, Alborz Province, Iran. Fish specimens from thirty-three sites were sampled by electrofishing device in October 2014. The habitat parameters, including elevation (m), water depth (cm), river width (m), river slope (%), current velocity (m.s-1), number of large stone (> 15 cm), average stone diam...

Data Envelopment Analysis (DEA) has been long employed as a popular methodology to evaluate the performance of various production activities with multiple inputs and outputs. However, an important issue is that the production process in the real world inevitably generates undesirable outputs (like wastes and pollutants) along with desirable outputs. Therefore, the undesirable outputs should be ...