52 Pages Posted: 26 Oct 2015 Last revised: 7 Jul 2017
Date Written: July 6, 2017
We decompose daily stock returns into news- and non-news-driven components, using a comprehensive sample of intraday firm-level news arrivals matched with high-frequency movements of their stock prices. We find that, consistent with prior literature, non- news returns precede a reversal. For news-driven returns, however, we find strong evidence of return continuation without subsequent reversals. A strategy of news momentum that buys stocks with high news returns and sells stocks with low news returns generates an annualized return of 40.08% in the following week, with a four-factor alpha of 40.44%, controlling for the market, size, value, and momentum. The strategy’s profitability is driven by positive serial correlations in individual stock returns, and is particularly pronounced for overnight and weekend news and among small firms with low analyst coverage, high volatility, and low liquidity. These results suggest that investor under-reaction to news, coupled with limits to arbitrage, drives news momentum.
Keywords: News; Momentum; Reversal; Underreaction; Attention; Limits to Arbitrage
JEL Classification: G02, G10, G14
Suggested Citation: Suggested Citation
By Andrew Ang