Cost efficiency

The Malmquist Index (MI) is a tool for analyzing the productivity. Considering its importance, different suggestions and studies have been offered on the Cost Malmquist Productivity Index (CMPI) according to existing conditions of decision making units (DMUs) and the available data. The present research aimed to provide a CMPI in a non-competitive environment in which the price data changes from one evaluation unit to another. Given the deficiency of Farrel’s cost efficiency (1957) and also the cost efficiency model presented by Tone (2002), and by taking advantage of the idea of changing the productivity of DMUs at different time periods, we presented cost Malmquist Productivity Index in the presence of non-identical prices for various DMUs, Then, we evaluate the data of the Iranian Stock Exchange by aforementioned Cost Malmquist Productivity index

The soundness and efficiency of banks is one of the important subjects that neglecting it can have adverse consequences for every country's economy. For economies depending on the money market, such as the Iran economy, this subject is more critical. Therefore, in this study, using panel data related to 16 Iranian banks for the annual period of 2010-2017, the economic efficiency was determined using a translog cost function and stochastic frontier analysis method then, by estimating the model of panel vector autoregression model and Granger causality test, the causal relationships between efficiency and information asymmetry in terms of adverse selection ( the ratio of loans to assets and the ratio of loans to deposits) and moral hazard ( the ratio of non-performing loans), were investigated, both of which are caused due to the information asymmetry. The estimations confirm the unilateral causal relationship of adverse selection and moral hazard with banking system efficiency. And, on the contrary, they claim that low efficiency of the banking system increases the adverse selection and moral hazard is not confirmed. Besides, the results of other estimates based on the panel model with random effects indicate a negative and significant impact of moral hazard and adverse selection on efficiency.