Cowards and Heroes: Group Loyalty in the American Civil War
研究美国内战中士兵为何在低薪、惩罚弱的情况下仍愿冒死，发现群体忠诚通过社会资本形成，公司层面的同质性（如种族、职业、年龄）比意识形态或士气更能预测忠诚度。
What motivated men to risk death in the most horrific war in U. S. history when pay was low and irregular and military punishment strategies were weak? In such a situation creating group loyalty by promoting social capital is of paramount importance and in the Civil War was the cement of both armies. We find that individual and company socioeconomic and demographic characteristics, ideology, and morale were important predictors of group loyalty in the Union Army. Company characteristics were more important than ideology or morale. Soldiers in companies that were more homogeneous in ethnicity, occupation, and age were less likely to shirk.