How Much Do Directors Influence Firm Value?
利用董事关联公司股票收益的共性，估计董事平均每年导致公司价值波动近1%，且董事劳动力市场未能实时评估其影响。
Abstract The value a director provides to a firm is empirically difficult to establish. We estimate that value by exploiting the commonality in idiosyncratic returns of firms linked by a director and show that, on average, a director’s influence causes variation in firm value of almost 1% per year. The return commonality is not due to industry or other observable economic links. Variation in the availability of information on shared directors and a placebo test exploiting the timing of shared directors provide further identification. The results also imply that the directorial labor market does not fully assess directors in real time.