9.1 Portfolio Risk and Return: Part 1 Flashcards
Historical returns
document past performance
expected returns
reflect anticipated future performance
An asset’s expected return is a function of the real risk-free rate, expected inflation, and any risk premiums that investors require as compensation
Using a mean and variance approach assumes that
assumes that returns are normally distributed and that markets are informationally and operationally efficient.
However, these assumptions do not necessarily hold.
A normal distributions has three characteristics:
- Its mean and median are equal.
- It is completely defined by its mean and variance
- It is symmetric around its mean.
Utility
measures the relative satisfaction gained from a particular portfolio
The utility that investors derive from an asset or portfolio is a function of their degree of risk aversion, which is the marginal reward that they require as compensation for taking an additional unit of risk
The key conclusions from utility functions are:
- Utility has no maximum or minimum
- A higher return contributes to higher utility
- Higher variance reduces utility (for risk-averse investors)
- Utility is only useful in ranking investment options
Indifference curves
plot the risk-return pairs that have the same utility.
For risk-averse investors, the slope will be positive.
All the points on a particular indifference curve have the same utility.
Greater utility is present on higher indifference curves, as shown in the diagram below.
Indifference curves are steeper for investors that are
more risk-averse
The capital allocation line (CAL)
represents the investment options for this portfolio of two securities.
It is the plot of different risk-return combinations derived by changing the weights of the two securities.
The CAL represents all the investment options. An investor must be somewhere on the line
what does the slope of the capital allocation line (CAL) represent?
the additional return required for every increment in risk, which is the market price of risk
The slope is equivalent to the Sharpe ratio.
The covariance between the returns on two assets is calculated as:
the product of their correlation and the individual standard deviations
The minimum-variance frontier
the left edge of the possibilities in the graph below
It represents the least portfolio risk that can be obtained for a given expected return
The global minimum-variance portfolio
located on the far left of the curve, is the least risky of the minimum variance portfolios.
the Markowitz efficient frontier
The section of the minimum-variance frontier that lies above the global minimum-variance portfolio
Risk-averse investors will not consider portfolios on the lower half of the minimum-variance frontier because, for any portfolio that plots in this section, there is a Markowitz efficient frontier that offers a higher expected return for the same level of risk.
According to the two-fund separation theorem
all investors will use the risky portfolio P to a greater or lesser extent depending on their level of risk aversion
Investors will have different allocations to the risk-free asset, but they will all create portfolios that use the optimal portfolio, P, and plot on the CAL according to their risk tolerance