本研究以日本國內產物保險公司作為研究對象，研究期間為1986年至2010年，共25個年度。本研究應用固定效果之GMM（一般化動差法）模型，以Lerner index衡量市場獨占力（競爭度），檢驗對日本產險公司之市場獨占力（競爭度）對於公司的財務穩定度以及各種風險之影響，包括總風險、核保風險以及投資風險。本研究發現日本國內產險公司獨占力與各風險大多存在負相關：越高獨占力（越低競爭度）的公司其總風險及核保風險越低。然而，越高獨占力（越低競爭度）的公司容易面對越高的投資風險。本研究結果亦顯示，獨占力對於風險之影響於1997至2010之研究期間有顯著效果，惟其於1986至1996之研究期間效果不顯著。 / This paper chooses Japanese domestic general insurance company as the objective and the research period is from 1986 to 2010, 25 sample years in total. We apply fixed-effect in the GMM (Generalized method of moments) to examine the impact of the market power (Lerner index) specifically in insurance market on financial stability and different risks of insurance company, including total risk, underwriting risk and investment risk. The result suggests in general, negative relation exist between market power and risks in Japanese domestic general insurance industry: We find that the higher the market power (the lower competition), the lower the total risk and underwriting risk. On the other hand, higher marker power (lower competition) leads to higher investment risk. Our finding also shows that market power has an impact in the period 1997-2010 but not for the period of 1986-1996, which confirms that Japanese financial reform in 1996 might have influence on risks and financial stability.

This paper explores the interrelationship between the net interest margin (NIM) and noninterest income and their determinants for banks in 9 Asian countries over the period 1998-2010. A simultaneous equations system is used to deal with endogenous regressors and its structural parameters are identified under a heteroskedastic covariance restriction, proposed by Lewbel (2012). The renovated Lerner Index proposed by Huang et al. (2013) is factored as a more robust proxy for market power over HHI. Our results demonstrate significantly positive relationship between the NIM and noninterest income, suggesting overall benefits for banks from income diversification. In addition, the loss-leader behavior is not supported in the sample countries.