本文将口口相传式社会性学习和从众心理这两种社会交互的渠道区分开来,并研究它们对于中国股票市场参与的影响。在本文的理论框架下,口口相传交流后产生的股票市场期望收益率和其历史最高值之差与上一期总开户比率是这两种渠道分别影响当期投资者开户率的主要自变量。实证研究表明:在控制了公共信息等一系列因素后,这两种渠道对股票开户决策均有显著影响。进一步发现,口口相传式的交流在大部分省的影响均是显著的,而从众心理只在极少数省显著,表现出前者是更重要的社会性影响方式。同时,对于口口相传式交流的影响程度越强的省份,其该省上市公司的平均回报率也更高。这两种社会性因素的影响强度也显示出较强的季节性,即在夏天的影响比冬天更大,与人们在夏天比冬天更容易从事社会交往的直觉吻合的。
This paper explicitly distinguishes word-of-mouth communication from social conformity in analyzing aggregate stock market participation in China. Our theoretical framework identifies the expected return shock under word-of-mouth communication and lagged participation rate as the key variables affecting participation in the two models, respectively. The empirical results show that there are significant effects of both models, even after controlling for the impact of public information. The impacts of the two channels also demonstrate substantial heterogeneity across province and month, and are shown to be related to stock returns.