Explaining the Diversification Discount
认为多元化折价不一定说明多元化破坏价值，因为企业是自主选择多元化的。使用三种计量方法控制内生性后，发现折价下降甚至转为溢价，说明需考虑自选择问题。
ABSTRACT This paper argues that the documented discount on diversified firms is not per se evidence that diversification destroys value. Firms choose to diversify. We use three alternative econometric techniques to control for the endogeneity of the diversification decision, and find evidence supporting the selfselection of diversifying firms. We find a strong negative correlation between a firms choice to diversify and firm value. The diversification discount always drops, and sometimes turns into a premium. There also exists evidence of selfselection by refocusing firms. These results point to the importance of explicitly modeling the endogeneity of the diversification status in analyzing its effect on firm value.