asset management lecture 12. outline of today’s lecture dollar- and time-weighted returns universe...
Post on 21-Dec-2015
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Outline of today’s lecture
Dollar- and Time-Weighted Returns Universe comparison Adjusting Returns for Risk
Sharpe measure Treynor measure Jensen measure Information ratio M2 measure
The choice of measure
Text Example of Multi-period Returns
0 1 2
Purchase 1 share at $50
Purchase 1 share at $53
Stock pays a dividend of $2 per share
Stock pays a dividend of $2 per share
Stock is sold at $54 per share
Text Example of Multi-period Returns
Dollar-Weighted Return Time-Weighted Return
%117.7
)1(
112
)1(
5150
21
r
rr%66.5
53
25354
%1050
25053
2
1
r
rInternal Rate of Return:
rG = [ (1.1) (1.0566) ]1/2 - 1 = 7.83%
•Internal rate of return considering the cash flow from or to investment; •Returns are weighted by the amount invested in each stock
Equal weighting
Universe comparisonComparison with other managers of
similar investment styleMay be misleading
Portfolio characteristics are not comparableSurvivorship bias
Universe comparison
95th percentile
5th percentile
The median
1) Sharpe Index
rp = Average return on the portfolio
rf = Average risk free rate
p= Standard deviation of portfolio
return
Risk Adjusted Performance: Sharpe
( )P f
P
r r
2) Treynor Measure
rp = Average return on the portfolio
rf = Average risk free rate
ßp = Weighted average for portfolio
Risk Adjusted Performance: Treynor
( )P f
P
r r
Risk Adjusted Performance: Jensen
3) Jensen’s Measure
p= Alpha for the portfolio
rp = Average return on the portfolio
ßp = Portfolio Beta
rf = Average risk free rate
rm = Average return on market index portfolio
( )P P f P M fr r r r
Risk Adjusted Performance: Information Ratio
Information Ratio
Information Ratio divides the alpha of the portfolio by the nonsystematic risk
p / (ep)
Nonsystematic risk could, in theory, be eliminated by diversification
Risk Adjusted Performance: M2
2*P MM r r
•rp* = return of a hypothetical portfolio made up of T-bills and the managed portfolio that has the same standard deviation as the market index portfolio
•rM = return of the market index portfolio
MMpMp SSrrM )(*2
Risk Adjusted Performance
( )P f
P
r r
( )P f
P
r r
( )P P f P M fr r r r
p / (ep)
2*P MM r r
Sharpe
Treynor
Jensen
Information ratio
M2
It depends on investment assumptions If the portfolio represents the entire
investment for an individual compared to the market (passive strategy) Sharpe Index or M2
If the portfolio is one of many portfolios combined in a large fund
There exist many alternative portfolios Jensen The Treynor measure: more complete because it
adjusts for risk
The choice of measure
Example: comparing two risky portfolios
%3%10*60.1%19
%2%10*90.0%11
Q
P
a
a Jensen’s measure:
Portfolio Q is preferred.
Example: comparing two risky portfolios
Nonsystematic risk will be diversified away in a well diversified fund.
Example: comparing two risky portfolios
Suppose that you form a portfolio with risk-free assets and portfolio P (or Q), then all possible portfolios lie along the TP line (or TQ line)
Treynor measure:
p
fpP
rrT
TP = 11% / 0.9 = 12.2%
TQ = 19% / 1.6 = 11.88%