Post–earnings-announcement drift (abbr. PEAD) is a well-researched phenomenon that describes the tendency for a stock’s cumulative abnormal returns to drift in the direction of an earnings surprise for some time (several weeks or even several months) following an earnings announcement. There have been many explanations for the existence of this phenomenon. One of the most widely accepted explanations for the effect is that investors under-react to the earnings announcements. Although we already addressed such an effect in some of our previous articles and strategies, we now present a handy method of improving the PEAD by using linguistic analysis of earnings call transcripts.

Earnings announcement days are really important dates in a usual yearly corporate routine. The stock market usually reacts sharply on earnings announcement news and stocks on average earn statistically significant return excess of the market over the short window centred around the announcements. But how does the movement of stocks look before earnings announcement? The recent research paper written by Gao, Hu, and Zhang analyzes price action before and after earnings announcement and shows that a majority of the announcement month premium is realized during the pre-announcement period. Stocks with higher levels of uncertainty (stocks are sorted based on their option implied volatilities) experience larger pre-announcement returns and more uncertainty resolution during the pre-announcement period…

Authors: Gao, Chao and Hu, Grace Xing and Zhang, Xiaoyan.

Title: Uncertainty Resolution Before Earnings Announcements