Deeply Learned Management Sentiment as Stock Return Predictor

Can investors apply deep learning software to expose obscure but useful management sentiment in firm SEC Form 10-K filings? In their July 2019 paper entitled “Is Positive Sentiment in Corporate Annual Reports Informative? Evidence from Deep Learning”, Mehran Azimi and Anup Agrawal apply deep learning to detect positive and negative sentiments at the sentence level in 10-Ks. They train their model using 8,000 manually evaluated sentences randomly selected from 10-Ks. They then use the trained model to assign sentiments to all sentences in each 10-K. Their overall measure of negative (positive) sentiment is number of negative (positive) sentences divided by the total number of sentences in the 10-K. They assess impact of 10-K sentiment on stock performance based on 4-factor (market, size, book-to-market, momentum) alpha during short intervals after 10-K filing. Using 10-K filings for non-utility and non-financial U.S. public firms with at least 200 words, associated daily stock prices/trading volumes and daily 4-factor alphas during January 1994 through December 2017, they find that: (more…)