STOUMBOS Robert, ERTAN Aytekin, KAROLYI Stephen A., KELLY Peter W.
We propose that extrapolative beliefs about earnings announcement (EA) returns may contribute to the understanding of EA return patterns. We construct a theoretically motivated measure of extrapolative investors’ expectations based on a stock’s recent history of EA returns. We then show that this measure explains cross-sectional variation in stock returns and investor behavior around EAs. Stocks expected to have high EA returns, according to our measure, experience predictable increases in prices before EAs and predictable decreases afterward. These patterns are economically significant: investors that buy (sell) a portfolio that is long firms with high recent EA returns and short firms with low recent EA returns in the pre-EA (post-EA) period earn daily five-factor abnormal returns of 16.1 bps (18.3 bps). Using individual investor trades data and a measure of institutional trading, we find that individual and institutional investors are more likely to purchase stocks with high recent EA returns, consistent with at least a subset of investors forming extrapolative beliefs about EA returns.
ERTAN, A., KAROLYI, S.A., KELLY, P.W. et STOUMBOS, R. (2022). Earnings announcement return extrapolation. Review of Accounting Studies, 27(1), pp. 185-230.