Political Geography, Myside Bias, and Retail Investor Behavior
利用PSID家庭数据和详细经纪记录，研究发现政治倾向一致的州的投资者更信任市场、更受同伴交易影响，并更易出现本地偏好、处置效应和过度自信等行为偏差，且政治情绪强烈时效应更显著。
ABSTRACT We examine how political geography shapes retail investor behavior through partisan myside bias—a location‐specific form of confirmation bias. Using household‐level data from the Panel Study of Income Dynamics (PSID) and detailed brokerage records, we find that investors in politically aligned states exhibit greater trust in the market, stronger peer‐driven trading, and a higher tendency toward behavioral biases such as local bias, disposition effect, and overconfidence. These effects are most pronounced when political sentiment is strong, highlighting how regional partisanship can distort financial decision‐making.