Naïve Buying Diversification and Narrow Framing by Individual Investors
研究区分个人投资者是均衡整体投资组合（天真组合分散化）还是均衡同日购买多只资产的金额（天真购买分散化），发现后者更普遍，源于选股行为和对分散化的忽视。
ABSTRACT We provide the first tests to distinguish whether individual investors equally balance their overall portfolios (naïve portfolio diversification, NPD) or, in contrast, equally balance the values of same‐day purchases of multiple assets (naïve buying diversification, NBD). We find NBD in purchases of multiple stocks, and in mixed purchases of individual stocks and funds. In contrast, there is little evidence of NPD. Evidence suggests that NBD arises due to stock picking behavior and neglect of diversification. These findings suggest that behavioral finance theory should incorporate transaction, as well as portfolio, framing.