Extrapolative Beliefs and the Value Premium
thesisposted on 22.07.2021, 19:33 by Zhaojing ChenZhaojing Chen
In models of stock returns where investors with extrapolative beliefs on future stocks (e.g., Barberis and Shleifer (2003)), price momentum and the value premium both arise naturally. The key insight from these models is that, the strength and timing of these cross- sectional return anomalies will be conditional on the degree of extrapolative bias. More specifically, higher (lower) degree of over-extrapolation leading to stronger value premium (momentum).
Using the time-series variation in the degree of over-extrapolation documented in Cassella and Gulen (2018), I first directly test the hypothesis that both value and momentum stem from over-extrapolation in financial markets. I find that the average momentum return is 1.00% (0.10%) per month when the degree of over-extrapolation is low (high), whereas the average value premium is 0.51% (1.29%) per month following low (high) levels of over- extrapolation.
Furthermore, I extend the model in Barberis and Shleifer (2003) by having both within- equity extrapolators and across asset-class extrapolator. The extension is based on the idea that when extrapolators move capital in and out of the equity market, they disproportionately buy growth stocks in good times and sell value stocks in bad times. The model predicts that the cross-sectional value premium should be stronger following states of large market- wide over- or undervaluation due to additional extrapolative demand to buy or sell. This prediction is tested empirically and I find strong support for it. The value premium is 3.42% per month following market-wide undervaluation and 1.70% per month following market overvaluation. In the remainder 60% to 80% of the sample, when the market is neither significantly over or under-valued, there is no significant value premium in a monthly horizon and the value premium is only 0.54% per month in an annual horizon. I provide some suggestive evidence regarding portfolio return dynamics, investor expectation errors and fund flows that supports the extrapolative demand channel. Overall, this work examines more closely at the effect of extrapolative beliefs on the cross-section of asset prices and offers some support for extrapolation-based asset-pricing theories.