Essentials of Investments: Chapter 18 - Active Management and Performance Measurement to introduce the most widespread approaches to risk adjustment for performance evaluation. It includes Introduction, The Conventional Theory of Performance Evaluation, Market Timing.
Trang 1Chapter 20
Active Management
and Performance
Measurement
Trang 2Chapter Summary
Objective: To introduce the most
widespread approaches to risk
adjustment for performance evaluation
Introduction
The Conventional Theory of Performance Evaluation
Market Timing
Trang 3Are markets totally efficient?
Some managers outperform the market for extended periods
While the abnormal performance may not
be too large, it is too large to be attributed solely to noise
Evidence of anomalies such as the turn of the year exist
The evidence suggests that there is some role for active management
The Objective of Active
Management
Trang 4 Complicated subject
Theoretically correct measures are
difficult to construct
Different statistics or measures are
appropriate for different types of investment decisions or portfolios
Many industry and academic measures
are different
The nature of active management leads
to measurement problems
Introduction to Performance Appraisal
Trang 5What is abnormal?
Abnormal performance is measured:
Benchmark portfolio
Market adjusted
Market model / index model adjusted
Reward to risk measures such as the
Sharpe Measure:
E (rp-rf) / sp
Abnormal Performance
Trang 7Summary Reminder
Objective: To introduce the most
widespread approaches to risk
adjustment for performance evaluation
Introduction
The Conventional Theory of Performance Evaluation
Market Timing
Trang 81) Sharpe Index
rp = Average return on the portfolio
rf = Average risk free rate
sp = Standard deviation of portfolio return
Risk Adjusted Performance: Sharpe
Trang 92) Treynor Measure
Risk Adjusted Performance: Treynor
rp = Average return on the portfolio
rf = Average risk free rate
bp = Weighted average b for portfolio
Trang 10Risk Adjusted Performance: Jensen
3) Jensen’s Measure
p = alpha for the portfolio
rp = Average return on the portfolio
rf = Average risk free rate
bp = Weighted average b for portfolio
rm = Average return on market index portfolio
Trang 11Appraisal Ratio
Appraisal Ratio = p / s(ep)
Appraisal Ratio divides the alpha of the
portfolio by the nonsystematic risk
Nonsystematic risk could, in theory, be
eliminated by diversification
Trang 12M2 Measure
Developed by Modigliani and Modigliani
Equates the volatility of the managed
portfolio with the market by creating a
hypothetical portfolio made up of T-bills
and the managed portfolio
If the risk is lower than the market,
leverage is used and the hypothetical
portfolio is compared to the market
Trang 13M2 Measure: Example
Managed Portfolio: return = 35% st dev = 42%
Market Portfolio: return = 28% st dev = 30% T-bill return = 6%
Hypothetical Portfolio:
30/42 = 714 in P (1-.714) or 286 in T-bills
(.714) (.35) + (.286) (.06) = 26.7%
Since this return is less than the market, the
managed portfolio underperformed
Trang 14It depends on investment assumptions
1) If the portfolio represents the entire
investment for an individual, Sharpe Index compared to the Sharpe Index for the
market
2) If many alternatives are possible, use the Jensen or the Treynor measure
The Treynor measure is more complete
because it adjusts for risk
Which Measure is
Appropriate?
Trang 15 Assumptions underlying measures limit
their usefulness
When the portfolio is being actively
managed, basic stability requirements
are not met
Practitioners often use benchmark
portfolio comparisons to measure
performance
Limitations
Trang 16 Wilfred Vos proposed a new measure
that also captures skewness: VVR (Vos
Value Ratio)
Trang 17Summary Reminder
Objective: To introduce the most
widespread approaches to risk
adjustment for performance evaluation
Introduction
The Conventional Theory of Performance Evaluation
Market Timing
Trang 18 Adjust the portfolio for movements in the market
Shift between stocks and money market
Trang 19r
rM
Rate of Return of a Perfect Market Timer
Trang 21 Switch to T-Bills in 90 and 94
Trang 22 Long horizon to judge the ability
Judge proportions of correct calls
Bull markets and bear market calls
With Imperfect Ability to
Forecast
Trang 23Adjusting portfolio for up and down movements in the market
Low Market Return - low ßeta
High Market Return - high ßeta
Identifying Market
Timing
Trang 25 Concentrate funds in undervalued stocks
or undervalued sectors or industries
Balance funds in an active portfolio and
Trang 26 Two major problems
Need many observations even when portfolio mean and variance are constant
Active management leads to shifts in parameters making measurement more difficult
To measure well
You need a lot of short intervals
For each period you need to specify the makeup of the portfolio
Complications to Measuring Performance