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Why Negative-Beta Assets Can Have Lower Expected Returns

Article Quant Q&A · Author: Uriel Katz

Summary

This discussion explains the CAPM intuition for why an asset with negative market beta may have a lower expected return than the risk-free rate, even if its standalone volatility matches that of a positive-beta asset. CAPM relates expected return to systematic exposure to the market portfolio, rather than to total volatility considered on its own. An asset that tends to perform well when the market or consumption is weak can provide valuable insurance, so investors may accept a lower return to hold it.

A two-state illustration contrasts assets that pay differently across high- and low-consumption conditions, emphasizing that the timing of returns matters. A second answer notes that diversification makes portfolio risk more relevant than an individual asset's standard deviation, and describes the CAPM relationship between beta and expected return. The discussion is conceptual rather than empirical; its simplified state example does not establish real-world returns, and the claims depend on the CAPM assumptions and interpretation of consumption risk.

Key ideas

  • CAPM links expected return to market beta rather than standalone volatility alone.
  • Negative-beta assets can hedge market downturns and may therefore offer lower expected returns.
  • An asset's payoffs across economic states help explain its risk premium.
  • Portfolio risk depends on how an asset covaries with the market portfolio.

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Full text
# Why do stocks with a negative beta return less than the risk free rate?


# Why do stocks with a negative beta return less than the risk free rate?












Let's say we have two stocks, Stock A and Stock B.

Both of them have the same standard deviation $\sigma$, and therefore have the same risk.

The only difference is that Stock A has a perfect positive correlation $\rho=1$ to the market ($\beta>0$), while Stock B has a perfect negative correlation $\rho=-1$ to the market of ($\beta<0$).

According to CAPM, Stock B should pay me less than the market risk-free rate while Stock A should pay me more. If both have the same amount of risk, i.e. standard deviation, then why does Stock B pay me less than Stock A?

I can only think of two reasons:

- There is less market supply of negative $\beta$ stocks than positive $\beta$ stocks, and therefore a higher price for negative $\beta$ stocks and lower returns.

- Since the market generally has positive returns (and a positive E[r]), a stock with a market correlation ($\rho$) of -1 has generally negative returns (and a negative E[r]).

Anyone care to give their opinion on this?

## Answer by benjaminmgross (score 3, accepted)

https://quant.stackexchange.com/a/9498

Focusing on intuition rather than theory, $\beta$ can also be thought of as the "risk premium" of that specific asset relative to the market.

In general, market risk premium links two very important aspects of the world: Consumption & Return. So if we look at the world in two states, an "Up State" & "Down State", here is what we would see:

### States:



- Down State Consumption Low Probability: 50%

### Risk Free Asset:

Price: 10





### Stock A

Price : 20





### Stock B

Price: 20





We can calculate the $\mathbb{E}[r]$ for each asset by using the formula $\mathbb{E}[r] \triangleq \frac{EV}{BV}-1$. If we multiply the final value by the probabilities, we can see that each asset has a return of $\frac{40\cdot .5 + 10\cdot .5}{20} - 1 = 0.25$.

So what's the difference? The difference between the two assets are what they pay during different levels of consumption.

In the "Up State," Consumption is high. In historical terms, think of early 2007 or 2000 -- nobody wants a stock that is paying a 1% return (recall how frothy the stock market was and how compressed yield spreads were). In the down state, Consumption is low, think of 2002 or 2008, people weren't spending -- they were paying down their debts and increasing savings. So an investment with a "positive risk premium" (Asset A) or "positive $\beta$" pays you a high return when consumption is high and a low return (i.e. loss) when consumption is low.

That's why Stock A pays you more, you must be compensated for taking the added risk of really bad returns when consumption is low, that's what "compensatory" or market risk is based on -- illustrated by an upward sloping, convex utility function of consumption.

## Answer by user70160 (score 0)

https://quant.stackexchange.com/a/17648

The standard deviation of an asset is less relevant if you hold a portfolio and not a single asset.

In the CAPM, every investor holds the same portfolio of risky assets - the market portfolio.

The CAPM implies further that the market portfolio has the highest expected portfolio return per unit of portfolio standard deviation of all possible portfolios.

This property leads mathematically to a positive linear relationship between expected return and beta, with expected returns for stocks with negative beta being negative as well.

Beta is negative if the correlation of the stock with the market portfolio is negative. So with your suggestion 2. you are probably not too far off.

Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.