Interstate migration networks and stock return comovement
研究发现美国各州之间移民流动会带来股票收益的额外联动，且这种联动随移民网络规模增强，部分源于移民投资者对原籍地股票的偏好。
Abstract We document sizable and robust excess return comovement between migration‐flow receiving and sending states at the state‐portfolio level. Migration comovement is not fully explained by economic fundamentals and strengthens with the size of the migration network. Consistent with the view that it is partially driven by correlated trading of a common investor base within migration networks, migration comovement a) increases substantially when there is an exogenous positive shock to migration flows, b) is greater with old firms in migration‐sending states, and c) strengthens when retail investors display “old home” bias in addition to local bias.