Quant Matters – The Search for Asymmetry: Realized Skewness in the Equity Cross-Section

Research evidence excerpt

Quant Matters – The Search for Asymmetry: Realized Skewness in the Equity Cross-Section

Global IdeaM

Topic of the Month – The Search for Asymmetry: Realized

Skewness in the Equity Cross-Section

Investors rarely experience risk symmetrically. Equity markets may compound gradually

over time, yet individual stocks can reprice abruptly following, for instance, an earnings

disappointment, funding shock or crowded-position unwind. Volatility treats large gains

and losses equally, measuring only the magnitude of return fluctuations. Skewness

provides a different perspective by capturing the asymmetry of the return distribution

and, in particular, the tendency of assets to experience extreme upside or downside

outcomes.

The distinction is economically important. A large body of academic literature argues that

investors dislike assets exposed to severe downside tail risk and therefore demand

compensation for holding them. In the context of equities, this implies that stocks with

more negative Realized Skewness – those that have historically exhibited a greater

propensity for large downside moves – should offer higher expected returns as

compensation for bearing crash risk. At the same time, positively skewed stocks may

command lower subsequent returns because investors are willing to pay a premium

for lottery-like payoffs and the possibility of extreme upside outcomes.

This so-called 'skewness premium' has attracted significant attention in both theoretical

and empirical asset-pricing research. From the early work of Kraus and Litzenberger (1976)

and Harvey and Siddique (2000) through more recent studies, a recurring finding is that

Realized Skewness contains information about future returns. Yet the evidence is far from

unanimous.