Using proprietary data on millions of trades by retail investors, we provide the first large-scale evidence that retail short selling predicts negative stock returns. A portfolio that mimics weekly retail shorting earns an annualized risk-adjusted return of 9%. The predictive ability of retail...

We analyze the role of retail investors in stock pricing using a database uniquely suited for this purpose. The data allow us to address selection bias concerns and to separately examine aggressive (market) and passive (limit) orders. Both aggressive and passive net buying positively predict...

This paper tests whether stock market investors appropriately distinguish new and old information about firms. I define the staleness of a news story as its textual similarity to the previous ten stories about the same firm. I find that firms' stock returns respond less to stale news. Even so, a...

We identify model-free mispricing factors and relate them to global stock prices and investor beliefs. The factors measure variation in the relative mispricing of closed-end funds and their underlying assets. We design three factors to reflect the beliefs and capital flows of important...

This chapter reviews and synthesizes a rapidly growing subfield that analyzes the relation between media and financial markets. Research in this area identifies novel data sources, such as newspaper articles, Internet search queries, and posts on social networks, and employs inventive empirical...

We propose and estimate a structural model of daily stock market activity to test competing theories of trading volume. The model features informed rational speculators and uninformed agents who trade either to hedge endowment shocks or to speculate on perceived information. To identify the...