Investor behavior in the stock markets focusing on internet transactions

通过对标准化融资融券交易下融资融券交易者投资行为的研究发现，融资融券交易量的增加预示着未来股价的上涨。我们的发现表明，被视为非理性交易者的个人投资者比其他投资者拥有信息优势。这与过去文献中的发现完全相反。通过对日本和美国股票投资者的问卷调查，我们发现投资者预期的变化在90年代的长期低迷中起到了重要作用，美国90年代末的IT泡沫不是理性的泡沫，此外，我们还考察了日本和中国之间的股价相关性，发现从中国到日本存在单向因果关系，即中国的股价没有对日本的股价做出反应(Tsutsui and Hirayama，2009)。

Focusing on the investment behavior of margin traders under the standardized margin transactions, we find that the increase in margin buying predicts the increase in future stock price. Our finding implies that individual investors, considered to be as irrational traders, have the information advantage over other investors. This is completely opposite to the findings in the past literature. As per the study on stock investors in Japan and the U. S. using questionnaire survey, we showed that change in investors' expectation played an important role in causing a long slump in 1990s and that the IT bubble in the U. S. in the late of 1990s was not a rational one, Furthermore, we investigated interdependencies of stock prices between Japan and China to find that there exists uni-directionally causality from China to Japan ; in other words, Chinese stock prices do not respond to those of Japan(Tsutsui and Hirayama, 2009).