Effects of Corporate Diversification: Evidence From the Property–Liability Insurance Industry

Authors:
Publisher website
Google Scholar
Abstract
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.

This publication has 53 references indexed in Scilit: