Endogeneity and the Dynamics of Voluntary Disclosure Quality: Is there Really an Effect on the Cost of Equity Capital?*

Research on the effects of voluntary disclosure quality on the cost of equity capital is often plagued by endogeneity concerns. In this paper, I use a dynamic panel system GMM estimator, which provides internal instruments from the firm's history that directly address endogeneity arising from unobserved heterogeneity and simultaneity. By using hand-collected voluntary disclosure scores for firms listed in the Swiss stock exchange, I examine the dynamic relation between voluntary disclosure quality and the cost of equity capital in a panel over a period of 10 years. The results suggest that the relation between voluntary disclosure quality and the cost of equity capital becomes insignificant after controlling adequately for potential dynamic endogeneity, simultaneity, and unobserved heterogeneity.