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CHAPTER 18
EVALUATION OF PORTFOLIO PERFORMANCE
Answers to Questions
1. The two major factors would be: (1) attempt to derive risk-adjusted returns that exceed a
naive buy-and-hold policy and (2) completely diversifyi.e., eliminate all unsystematic
2. a) Treynor ratio and Jensen’s alpha measure risk by systematic risk, beta. The Sharp
ratio measure uses total risk, the standard deviation of returns over time. The information
ratio uses the standard deviation of excess returns where excess return is the difference
between the return on a portfolio and its benchmark. The Sortino ratio uses a semi-
deviation measure, including only those returns that fall below a specified minimum
3. For portfolios with R2 values noticeably less than 1.0, it would make sense to compute
both measures. Differences in the rankings generated by the two measures would suggest
4. Jensen’s alpha () is found from the equation Rjt RFRt == j + j[Rmt RFRt] +ejt. The
aj indicates whether a manager has superior (j > 0) or inferior (j < 0) ability in market
5. The Information Ratio (IR) is calculated by dividing the average return on the portfolio
less a benchmark return by the standard deviation of the excess return. The IR can be
6. Returns-based measures compare the actual returns on a portfolio to a benchmark. Sharpe
and Treynor are simple measures, comparing portfolio returns to a risk-free rate. The
information ratio and Sortino can use the returns of the benchmark portfolio as the
standard of comparison. Another type of returns-based analysis is returns-based style
7. The difference by which a manager’s overall actual return beats his/her overall
benchmark return is termed the total value-added return and decomposes into an
allocation effect and a selection effect. The former effect measures differences in weights
8.
8(a).
Benchmark
Explain two different weaknesses of using each of the
benchmarks to measure the performance of the portfolio.
Market
Index
A market index may exhibit survivorship bias; firms that have
gone out of business are removed from the index resulting in a
performance measure that overstates the actual performance had
the failed firms been included.
A market index may exhibit double counting that arises because
of companies owning other companies and both being represented
in the index.
It is often difficult to exactly and continually replicate the
holdings in the market index without incurring substantial trading
costs.
The chosen index may not be an appropriate proxy for the
management style of the managers.
The chosen index may not represent the entire universe of
securities (e.g., S&P 500 Index represents 6570 percent of U.S.
equity market capitalization).
The chosen index may have a large capitalization bias (e.g., S&P
500 has a large capitalization bias).
The chosen index may not be investable. There may be securities
in the index that cannot be held in the portfolio.
Benchmark
Normal
Portfolio
This is the most difficult performance measurement method to
develop and calculate.
The normal portfolio must be continually updated, requiring
substantial resources.
Consultants and clients are concerned that managers who are
involved in developing and calculating their benchmark portfolio
may produce an easily-beaten normal portfolio making their
performance appear better than it actually is.
able to invest in the median manager portfolio.
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(Continued)
Such a benchmark may be ambiguous. The names and weights of
the securities constituting the benchmark are not clearly
delineated.
The benchmark is not constructed prior to the start of an
evaluation period; it is not specified in advance.
A manager universe may exhibit survivorship bias; managers that
have gone out of business are removed from the universe resulting
in a performance measure that overstates the actual performance
had those managers been included.
8b)i.
The Sharpe ratio is calculated by dividing the portfolio risk premium, (i.e., actual
portfolio return minus risk-free return) by the portfolio standard deviation of return.
Sharpe Ratio = (Rp Rf)/p
The Treynor measure is calculated by dividing the portfolio risk premium (i.e., actual
portfolio return minus risk-free return) by the portfolio beta.
8(b).ii.
The Sharpe ratio assumes that the relevant risk is total risk and measures excess return
per unit of total risk.
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9.
9(a). The basic procedure in portfolio evaluation is to compare the return on a managed
portfolio to the return expected on an unmanaged portfolio having the same risk, via use
of the CAPM. That is, expected return (Rp) is calculated from:
Rp = Rf + p(Rm – Rf)
9(b). The benchmark error often occurs because the unmanaged portfolio used in the
evaluation process is not “optimized.” That is, market indices, such as the S&P 500,
9(c). The main ingredients are that the true risk-free rate is lower than the measured risk-free
9(d). The response depends upon one’s beliefs about whether these portfolios represent the true
market portfolio. The DJIA is comprised of only 30 industrial stocks; S&P 500 includes
9(e). Defense of CAPM: it is valid as a normative theory as it describes the proper measure of
risk (systematic risk, not total risk or another risk definition) and it shows what the
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10. When measuring the performance of an equity portfolio manager, overall returns can be
related to a common total risk or systematic risk. Factors influencing the returns achieved
by the bond portfolio manager are more complex. In order to evaluate performance based
CHAPTER 18
Answers to Problems
1(a).
.03
.07.10
1.30
.10
.13
.10
.07.20
S
60.1
.05
.08
0.05
.07.15
S
Q
P
==
=
==
=
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2.
2(a). The Treynor measure (T) relates the rate of return earned above the risk-free rate to the
portfolio beta during the period under consideration. Therefore, the Treynor measure
shows the risk premium (excess return) earned per unit of systematic risk:
0.60
1.00
The Treynor measure examines portfolio performance in relation to the security market
line (SML). Because the portfolio would plot above the SML, it outperformed the S&P
500 Index. Because T was greater than TM, 6.7 percent versus 6.0 percent, respectively,
Sharpe Measure Performance Relative to the Market (S&P 500)
Market (S&P 500)
2(b). The Treynor measure assumes that the appropriate risk measure for a portfolio is its
systematic risk, or beta. Hence, the Treynor measure implicitly assumes that the portfolio
being measured is fully diversified. The Sharpe measure is similar to the Treynor
measure except that the excess return on a portfolio is divided by the standard deviation
of the portfolio.
For perfectly diversified portfolios (that is, those without any unsystematic or specific
3(a). Portfolio MNO enjoyed the highest degree of diversification because it had the highest R2
(94.8 percent). The statistical logic behind this conclusion comes from the CAPM, which
says that all fully diversified portfolios should be priced along the security market line.
3(b). Note the mean returns are net of the risk-free rate. Doing the calculations we obtain:
Fund Treynor Sharpe Jensen
DEF 0.715(5) 0.619(5) -0.053(5)
JKL 1.262(2) 0.915(3) 0.355(2)
3(c).
Fund t(alpha)
DEF -0.2789(5)
JKL 1.6136(4)
Only GHI and MNO have significantly positive alphas at a 95% level of confidence.
4(a). Overall performance (Fund 1) = 26.40% – 6.20% = 20.20%
4(b). E(Ri) = 6.20 + (15.71 6.20)
4(c)(i). Selectivity1 = 20.2% – 12.85% = 7.35%
4(c)(ii).Ratio of total risk1 = 1/m = 20.67/13.25 = 1.56
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4(c)(iii). Net Selectivity = Selectivity Diversification
4(d). Even accounting for the added cost of incomplete diversification, Fund 1’s performance
was above the market line (best performance), while Fund 2’s performance fell below the
line.
5.
a.
Year
Mgr X
Return
Mgr Y Return
1
-1.5
-6.5
2
-1.5
-3.5
3
-1.5
-1.5
4
-1.0
3.5
5
0.0
4.5
6
4.5
6.5
7
6.5
7.5
8
8.5
8.5
9
13.5
12.5
10
17.5
13.5
Average
4.5
4.5
Std Dev
6.90
6.63
Semi-dev
0.65
4.20
Semi-deviation considers only the returns that are below the average.
b.
Sharpe ratio: (average return minus risk-free rate) / standard deviation
Mgr X:
0.435
Mgr Y:
0.452
Best performer
c.
Sortino ratio: (average return minus minimum acceptable return)/semi-
deviation
Mgr X:
4.602
Best performer
Mgr Y:
0.714
d. The Sharpe and Sortino measures should provide the same performance ranking when
the return distributions are symmetrical for the funds or managers under consideration.
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6.
6(a)(i). .6(-5) + .3(-3.5) + .1(0.3) = -4.02%
7.
7(a). Overall, both managers added value by mitigating the currency effects present in the Index.
Both exhibited an ability to “pick stocks” in the markets they chose to be in (Manager B
in particular). Manager B used his opportunities not to be in stocks quite effectively (via
the cash/bond contribution to return), but neither of them matched the passive index in
picking the country markets in which to be invested (Manager B in particular).
7(b). The column reveals the effect on performance in local currency terms after adjustment
for movements in the U.S. dollar and, therefore, the effect on the portfolio. Currency
gains/losses arise from translating changes in currency exchange rates versus the U.S.
8.
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8(a). Evaluation begins with selection of the appropriate benchmark against which to measure
the firms’ results:
Firm A. The Aggregate Index and “Managers using the Aggregate Index” benchmark are
Performance has been good (30 basis points ahead of the index and in the second quartile
of manager results) but not as good as Firm A’s showing during this relatively short
measurement period.
8(b). Firm A does not show an observable degree of security selection skill (-10 basis points);
nor does it appear to be managing in line with its stated marketlike approach. Some large
nonmarketlike bets are driving return production (e.g., duration bets, +100 basis points;
8(c). Firm C produced the best results because its style and its expertise were confirmed by the
9(a). Dollar-Weighted Return
Manager L:
500,000 = -12,000/(1+r) – 7,500/(1+r)2– 13,500/(1+r)3 – 6,500/(1+r)4– 10,000/(1+r)5+
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9(b). Time-weighted return
Manager L:
Periods HPR
1 [(527,000 500,000) 12,000]/500,000 = .03
2 [(530,000 527,000) 7,500]/527,000 = -.0085
Manager M:
Periods HPR
1 [(692,000 700,000) + 35,000]/700,000 = .03857
2 [(663,000 692,000) + 35,000]/692,000 = .00867
EV (1 DW)(Contribution)
9(c). Dietz approximation method = – 1
BV + (DW)(Contribution)
Manager M:
Periods HPY
1 [(692,000 (1 -.50)(-35,000)]/[700,000 + (.50)(-35,000)] 1
= (692,000 + 17,500/(700,000 17,500) 1 = 709,500/682,500 1 = .0396
2 (663,000 (1 -.50)(-35,000)]/[692,000 + (.50)(-35,000)] 1
10 (a) Average Return AFNDX-RF = 1.637
Average Return SPX-RF = 1.540
10(b)
SUMMARY OUTPUT
Regression Statistics
Multiple R
0.77359
R Square
0.598442
Adjusted R
Square
0.588146
Standard
Error
3.682119
Observation
s
41
ANOVA
df
SS
MS
F
Significan
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ce F
Regression
1
788.0144
788.014
4
58.1217
2
3.03E-09
Residual
39
528.7621
13.558
Total
40
1316.776
Coefficien
ts
Standard
Error
t Stat
P-value
Lower
95%
Upper
95%
Lower
95.0%
Upper
95.0%
Intercept
0.222915
0.604211
0.36893
5
0.71417
1
-0.99922
1.44504
6
0.99922
1.44504
6
SPX-RFR
0.918015
0.120415
7.62376
3.03E-
09
0.674453
1.16157
8
0.67445
3
1.16157
8
(1) One-factor Jensen’s alpha coefficient 0.2229
(2) Beta coefficient 0.9180
10 (c) Treynor’s ratio performance measure
10 (d) Although the portfolio has a low risk premium per unit of risk as indicated by the Sharpe
10 (e) The tracking error (TE) for AFNDX on a monthly basis is 5.738 and on an annualized
10 (f) The information ratio (IF) = 1.637/5.738 = 0.2853. This represents the manager’s average
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10(g).
SUMMARY OUTPUT
Regression Statistics
Multiple R
0.834821
R Square
0.696926
Adjusted R
Square
0.672352
Standard
Error
3.284201
Observation
s
41
ANOVA
df
SS
MS
F
Significan
ce F
Regression
3
917.6953
305.898
4
28.3607
5
1.07E-09
Residual
37
399.0812
10.7859
8
Total
40
1316.776
Coefficien
ts
Standard
Error
t Stat
P-value
Lower
95%
Upper
95%
Lower
95.0%
Upper
95.0%
Intercept
0.081039
0.540695
0.14988
0.88167
4
-1.01451
1.17659
1
1.01451
1.17659
1
Excess Mkt
0.895537
0.131509
6.80970
2
5.09E-
08
0.629075
1.162
0.62907
5
1.162
SMB
0.041786
0.129354
0.32303
8
0.74848
5
-0.22031
0.30388
3
0.22031
0.30388
3
HML
-0.18187
0.19729
0.92185
0.36257
7
-0.58162
0.21787
5
0.58162
0.21787
5
(1) Intercept coefficient is 0.08104 is statistically insignificant.
SMB 0.0418
(3) R-squared measure 0.6969 which is statistically significant.
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