CAPM Flashcards
Relationship between risk and return
Positive relationship between risk and realized return: The more risky an asset (higher volatility (st. dev.)), the higher the realized returns.
Individual stocks (risk and return)
Unlike the case for large portfolios, there is no precise relationship between volatility and average return for individual stocks. Individual stocks have higher volatility and lower average returns than the relationship shown for large portfolios. Hence, volatility does not explain returns of individual stocks.
Return of equities
Equities were the best performing asset class everywhere. The long-term real equity return was typically at level of 3% to 6% per year.
Relationship between risk premium and price
Inverse relationship between risk premium and price. Risky assets have relatively low price but a relatively higher expected return.
Investors demand compensation for…
- Abstaining from consuming today and waiting until tomorrow
- Taking on risk - measured by the risk premium.
Sources for Equity Risk Premium
- Survey based premiums
- Historical premiums
- Implied premiums
Skewness
A measure of symmetry, or more precisely, the lack of symmetry.
Positive - skewed right (right tail is heavier)
Negative - skewed left (left tail is heavier)
People like positive skew because it gives higher probability to end up in a positive area (investors are willing to pay premium for that).
Kurtosis
A measure of whether the data are peaked or flat relative to a normal distribution.
High kurtosis - distinct peak near the mean, decline rather rapidly, and have heavy tails.
Low kurtosis - flat top near the mean rather than a sharp peak
Positive excess kurtosis - “peaked” distribution (leptokurtic -> K>3); return series characterized by jumps, daily returns.
Negative excess kurtosis - “flat” distribution (platykurtic -> K<3)
Diversification
As long as asset returns are not perfectly correlated, the standard deviation (risk) of the portfolio is less than the weighted average of the assets standard deviations, diversification reduces variability of returns.
Market risk
Economy-wide sources of risk that affect the overall stock market (reason why stocks have a tendency to move together - common factor affecting all stocks)
Systematic, non-diversifiable
Unique risk
Risk factor affecting only that firm.
Non-systematic, idiosyncratic, diversifiable.
DIversification
By forming portf. of more than one asset, some of the volatility (risk) of individual assets is diversified away. Sicne investors can diversify away some of the risk for free, they can rationally only demand compensation for the systematic risk they carry.
Beta
The beta of individual security measures its sensitivity to market movements (marginal contribution to portfolio risk).
Beta-value for the risk free asset is zero since uncorrelated with the market portfolio.
Market portfolio perfectly correlated with itself.
The higher systematic risk - higher beta an asset has - the larger the expected return (positive relationship between systematic risk and expected return).
Investors are only compensated for the systematic risk as gauged by asset’s beta.
DIstribution
Stock prices follow lognormal distribution.
Stock returns follow normal distribution.
Efficient portfolio
Locus of all non-dominated portfolios in the mean-standard deviation space
By definition, no (“rational”) mean-variance investor would choose to hold a portfolio not located on the efficient frontier.