2Choi B P, Weiss M A. An empirical evaluation of market structure, efficiency, and performance in property - liability insurance[ J].Journal of Risk and Insuranee ,2005 (4): 635 - 673.
3Yoon S. A note on the market structure and performance in Korean manufacturing industries[ J ]. Journal of Policy Mod- eling,2004 (26) : 733 - 746.