Who are better monitors? Comparing styles of supervisory and independent directors

This paper compares the unobservable style effect between independent directors and supervisory directors on firm performance. Utilizing the unique Chinese board system with both independent and supervisory directors and a large panel data of 2,240 public firms from 2003 to 2017, this paper finds that both supervisory and independent style is crucial in determining variations of firm performance. The effects of both independent and supervisory director style are less significant when the “type II” agency problem is more severe in a firm. Moreover, outside independent director style is more effective when information costs are low or when firms need more outside resources, while inside supervisor director style is more effective when there are no major internal changes. Finally, the results also suggest that increasing qualified supervisor representations are beneficial to firms. • We compare the style effects between independent and supervisory directors. • Both supervisory and independent styles are crucial in firm performance. • Both styles are less significant when the “type II” agency problem is more severe. • Increasing qualified supervisor representations is beneficial to firms.