We study the effects of broadband internet use on the investment decisions of individual investors. A public program in Norway provides plausibly exogenous variation in internet use. Our instrumental variables estimates show that internet use causes a substantial increase in stock market participation, driven primarily by increased fund ownership. Existing investors tilt their portfolios toward funds, thereby obtaining more diversified portfolios and higher Sharpe ratios, and do not increase their trading activity in stocks. Overall, access to high-speed internet spurs a “democratization of finance,” with individuals making investment decisions that are more in line with the advice from portfolio theory.

中文翻译：

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宽带互联网与个人投资者的股票市场投资

我们研究宽带互联网的使用对个人投资者投资决策的影响。挪威的一项公共计划似乎提供了互联网使用的外生变化。我们的工具变量估计表明，互联网的使用导致股票市场参与度大幅增加，这主要是由基金所有权的增加推动的。现有投资者将投资组合向基金倾斜，从而获得更多元化的投资组合和更高的夏普比率，并且不会增加股票交易活动。总体而言，高速互联网的接入促进了“金融民主化”，个人做出的投资决策更符合投资组合理论的建议。