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Risk Aversion, Safe-Asset Demand, and the Risk-Free Rate

Article Quant Q&A · Author: Mike

Summary

The discussion examines whether greater risk aversion necessarily lowers the risk-free rate. One explanation uses the inverse relationship between bond prices and yields: stronger demand for Treasury bills can raise their prices and lower their yields, assuming supply is fixed. This offers a basic market-clearing intuition for why risk-free rates might fall as investors seek safety.

A contrasting answer derives the risk-free rate in a consumption-based model with constant relative risk aversion and lognormal consumption growth. In that setup, greater risk aversion can raise the rate through expected consumption growth, while a volatility-related precautionary term can push it down; the net effect depends on assumptions and parameter values. The answers thus show that a simple demand story and a general-equilibrium asset-pricing model need not imply the same direction. The excerpt does not reconcile the disagreement or provide empirical evidence, so the claimed relationship should not be treated as universal.

Key ideas

  • Higher demand for safe bonds can raise bond prices and lower yields when supply is fixed.
  • A consumption-based model can imply a higher risk-free rate as risk aversion increases.
  • The volatility-related precautionary term may offset the expected-growth effect.
  • The direction of the relationship depends on the model and its assumptions.

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Full text
# Risk aversion and risk-free rates


# Risk aversion and risk-free rates












New to finance. When I read textbook like Financial Economics by Bodie, I encountered the following idea, namely, higher risk aversion is associated with higher risk premium and lower risk-free rate.

I understand the risk premium part. But I cannot convince myself about the risk-free rate. Higher risk premium does not necessarily imply lower risk-free rate. I thought higher risk aversion should be associated with higher risk-free rate. My reasoning is that as more and more people get highly risk averse, more and more people will prefer risk-free assets to risky assets, the demand for risk-free assets increases. Simple supply and demand story tells us that higher demand of risk-free assets leads to higher prices or higher risk-free rates in this case (of course, if we hold supply constant). I do not know where my reasoning goes wrong.

## Answer by nbbo2 (score 2)

https://quant.stackexchange.com/a/42175

As we know from Bonds 101, the prices and yields of fixed income securities vary inversely. So your statement should be amended to read "higher demand of risk-free assets leads to higher prices or (equivalently) LOWER rates in this case".

For example suppose Tbills are priced at 98. Now risk aversion increases and there is a stronger demand for Tbills. The price might go to 99, so now they have a yield of barely 1.01% (I invest 99 and get back 100 a year later), instead of 2 point something previously.

## Answer by Irtza Ahmed (score 0)

https://quant.stackexchange.com/a/42176

Higher risk aversion implies lower risk-free rate, because when people are risk averse they demand more risk free assets or lower risk assets. Increase in demand for risk free assets, with their supply fixed leads to a lower price (interest rate).

Just demand and supply!

## Answer by YUE LI (score 0)

https://quant.stackexchange.com/a/50640

Indeed the demand for risk free assets increases but assets are different from goods. For goods, consumers pay the price but for assets, banks pay to consumers. With more consumers, banks have more power to argue price, so they would like to set a lower price: lower interest rate. For consumers, they want higher payoff but now they have lower market power so it’s opposite to what they want: lower payoff which is lower risk free rate.

## Answer by phdstudent (score -1)

https://quant.stackexchange.com/a/42177

I find that statement from Bodie weird. The most basic financial economics models have higher risk aversion implies higher risk free.

Assume there is a Lucas tree economy and that the utility is CRRA. Then the fundamental asset pricing formula implies that for any asset:

$$0 = \log E_t \bigg [R_{t+1}\beta \bigg ( \frac{C_{t+1}}{C_t} \bigg ) \bigg ]$$

Take the risk free and assume that $R_{t+1}$ and $C_{t+1}/C_t$ are jointly log normal:

$$r^f_{t+1} = 1/\beta + \gamma E_t(g_{t+1}) - \frac{1}{2}\gamma^2 \sigma^2_g$$

where $g_{t+1} \equiv C_{t+1}/C_t$.

So higher risk aversion implies higher risk free, unless the Jensen inequality term $\left(\frac{1}{2}\gamma^2 \sigma^2_g\right)$ starts dominating. As volatility of consumption growth is usually small this is not the case and usually we have:

$$\frac{\partial r^f_t }{\partial \gamma} > 0.$$

This is true in this simple model as well as more generally. Intuitively, the higher the risk aversion the higher the precautionary savings motive of agents so higher demand for safe assets. In general equilibrium regardless of whether the assets are in zero or positive net supply this leads to higher risk free rates.

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.