Premium
Effects of Corporate Diversification: Evidence From the Property–Liability Insurance Industry
Author(s) -
Liebenberg Andre P.,
Sommer David W.
Publication year - 2008
Publication title -
journal of risk and insurance
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 63
eISSN - 1539-6975
pISSN - 0022-4367
DOI - 10.1111/j.1539-6975.2008.00290.x
Subject(s) - diversification (marketing strategy) , endogeneity , equity (law) , business , liability , economics , line of business , actuarial science , econometrics , financial economics , monetary economics , finance , business model , marketing , business relationship management , political science , electronic business , law
Using a sample of property–liability insurers over the period 1995–2004, we develop and test a model that explains performance as a function of line‐of‐business diversification and other correlates. Our results indicate that undiversified insurers consistently outperform diversified insurers. In terms of accounting performance, we find a diversification penalty of at least 1 percent of return on assets or 2 percent of return on equity. These findings are robust to corrections for potential endogeneity bias, alternative risk measures, alternative diversification measures, and an alternative estimation technique. Using a market‐based performance measure (Tobin's Q) we find that the market applies a significant discount to diversified insurers. The existence of a diversification penalty (and diversification discount) provides strong support for the strategic focus hypothesis. We also find that insurance groups underperform unaffiliated insurers and that stock insurers outperform mutuals.