Efficiency and risk in Taiwan banking: SBM super-DEA estimation

In this study we adopt the two Data Envelopment Analysis (DEA) methods, including Banker-Charnes-Cooper (BCC) and Slacks-based Measure (SBM) super efficiency, to investigate whether a bank's technical efficiency index's results, incorporating account risk and not incorporating account risk, differ significantly. The information is obtained from 43 Taiwanese banks for the period 1998 to 2002. We also employ the nonradial and slacks-based Malmquist Total Factor Productivity (TFP) index to measure the impact of productivity change on the panel data. Our empirical results from the DEA approach are summarized as follows: (1) Loan quality factors have an impact on a bank's efficiency. In general, the bank with a higher degree of problem loans drops down its efficiency by incorporating account risk; however, the bank with a lower degree of problem loans increases its efficiency by incorporating account risk. (2) Super efficiency provides a good framework for ranking efficient units. (3) Based on the nonradial and slacks-based Malmquist TFP index, we find that bank productivity has increased and technical change has improved. (4) In Taiwan, bank with a higher performance will be more secure.