Exit versus Voice
研究在产生外部性的企业中，退出（撤资和抵制）与发声（股东参与）两种策略的相对有效性，发现多数投资者稍有社会责任感时发声更优，而多数自私时退出更有效但均难达最优。
We study the relative effectiveness of exit (divestment and boycott) and voice (engagement) strategies in a world where companies generate externalities and some agents care about the social impact of their decisions. We show that if the majority of investors are even slightly socially responsible, voice achieves the socially optimal outcome. In contrast, exit does not unless everybody is significantly socially responsible. If the majority of investors are purely selfish, exit is a more effective strategy, but neither strategy generally achieves the first best. We also show that exit can sometimes reduce social welfare.