Mutual funds and performance evaluation
Table of Contents
Quick Recap
Capital Allocation Line – Line created on a graph of all possible combination of risk-free and risky assets, and slope of which is known as reward-to-risk ratio.
- Used to choose how much to invest in a risk-free asset and one or more risky assets
- Based on the investor’s risk tolerance, these allocations can be made
Capital Asset Pricing Model
Model that describes the relationship between systematic risk and expected return for assets (stocks).
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Security Market Line – Visualization of CAPM, showing the relationship between risk (measured by beta) and expected return.
- An investment evaluation tool derived from the CAPM
- If expected return of a stock is above the SML, then the stock is undervalued or underpriced; Buy the stock
- If expected return of a stock is below the SML, then the stock is overvalued or overpriced; Sell the stock
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Capital Market Line – CAL where the risk portfolio is the market portfolio; Slope of the CML is the sharpe ratio of the market portfolio; Risk is measured by standard deviation
- Intercept point of CML and efficient frontier would result in the most efficient portfolio called the tangency portfolio.
A. Mutual funds
A mutual fund is a portfolio of financial securities. Many investors (typically investors) provide capital and a professional manager invests this ‘pool’ of capital in financial securities including stocks, bonds, money markets, etc.
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Passive management – Invest in a well-diversified portfolio without searching for security mispricing.
- Examples include index funds, ETFs, etc.
- Assumes the efficient market hypothesis is true
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Active management – Identifying the “mispriced” securities to beat the market
- Assumes the efficient market hypothesis is false
1. Net Asset Value (NAV)
NAV is the price per share of a mutual fund.$$\text{NAV} = \frac{\text{Market Value of Assets} - \text{Liabilities}}{\text{Number of Shares Outstanding}}$$
- Liabilities: Unpaid expenses, management fees, etc.
2. Mutual fund fees
- Front-end load – A fee charged when you buy the fund
- Front-end load does NOT affect NAV.
$$\text{Offer}_{t=0} = \frac{\text{NAV}_0}{1-\text{front-end load}}$$
- Back-end load – A fee charged when you sell the fund
- Back-end load does NOT affect NAV.
$$\text{Redeem}_{t=1} = \frac{\text{NAV}_1}{1-\text{back-end load}}$$
- Expense ratio – % of NAV each year
- The expense is calculated on the increased NAV after the front-end load
Always note the following:
- Make sure to subtract the expense ratio from the return; this return the current NAV
Calculating Returns
$$\text{Return}_{fund}=\frac{\text{Redeem} - \text{Offer} + \text{Distributions}}{\text{Offer}}$$
- what is distribution??
- Income - if mutual fund includes stocks, then it includes dividends or bond can payout coupons
$$\text{Return_fund}=\frac{\text{NAV}(1+\text{cap gain})(1-\text{exp ratio}) }{N}-1$$
B. Portfolio Performance Evaluation
1. Risk Model: Jensen’s Alpha
$$\alpha_P = \bar{R}_P - \beta_P \bar{R}_M$$
- $\alpha_P$ Portfolio alpha
- $\bar{R}_P$ Average excess return on the portfolio
- $\beta_P$ Beta of the portfolio
- $\bar{R}_M$ Average excess return on the market
2. Mutual Fund Performance
If markets are efficient, then before expenses, an average mutual fund has $\alpha = 0$.
- Across all fund managers, the average $\beta$ is 0
C. Selecting Funds/Portfolios in Practice
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Small investors select one portfolio (Entire-wealth portfolio).
- Select portfolio with the highest sharpe ratio
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Large investors hold many funds.
- Select funds using the
Treynor ratio
:
$$\text{Treynor ratio} = \frac{\bar{r_p} - \bar{r_f}}{\beta_p}$$
- $\bar{r_p}$ Average return on the portfolio
- $\bar{r_f}$ Average risk-free rate
- $\beta_p$ Beta of the portfolio
- Adding an actively managed portfolio: Information Ratio
- An actively managed portfolio delivers the benefit of $\alpha$, but adds idiosyncratic risk to our passive benchmark portfolio.
$$\text{Information ratio} = \frac{\alpha_p}{\sigma(e_p)}$$
- $\alpha_p$ per unit of unsystematic risk
- $\sigma(e_p)$ Standard deviation of the $e_p$ from an index model: $R_p = \alpha_p + \beta_p R_m + e_p$
Information Ratio is often used to evaluate hedge funds.
Hedge funds attempt to follow a market neutral strategy:
- Beta equals zero, so the fund is not exposed to market risk
- Alpha is positive
Performance Measure | Application |
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Sharpe Ratio | To select one fund: for use as the optimal risky portfolio |
Treynor Ratio | Select fund of funds: for many portfolios |
Information Ratio | Add to benchmark: For adding an active fund to an existing passive benchmark |