We employ a Wilcoxon signed rank test, with a null hypothesis that no differences exist between the efficiency scores of the BCC model and those of the DSBM model. We always reject the null hypothesis. Under the DSBM model, the median values of the Chinese life insurers from 2006 to 2010 are all consistently over 1. Moreover, we regress the operating efficiency scores on the exogenous factors, specifically intellectual capital. The truncated regression results prove that intellectual capital, which includes human capital, structural capital, and financial capital, have positively significant impacts on firm operating efficiency. The outcome confirms the importance of intellectual capital since the dimensions of intellectual capital are complementary.
Although there are advantages to using the DSBM model, it is nevertheless particularly challenging to hand collect the proprietary information of Chinese life insurance companies. When more information becomes available, future research could probably examine the association of other exogenous factors, such as corporate governance, with corporate performance.