Title: CIO Investment Course
1CIO Investment Course June 2007
- Topic Three
- Portfolio Risk Analysis
2Notion of Tracking Error
3Notion of Tracking Error (cont.)
4Notion of Tracking Error (cont.)
- Generally speaking, portfolios can be separated
into the following categories by the level of
their annualized tracking errors - Passive (i.e., Indexed) TE lt 1.0 (Note TE lt
0.5 is normal) - Structured 1.0 lt TE lt 3
- Active TE gt 3 (Note TE gt 5 is normal for
active managers)
5Index Fund Example VFINX
6ETF Example SPY
7Large Blend Active Manager DGAGX
8Tracking Errors for VFINX, SPY, DGAGX
9Chile AFP Tracking Errors Fondo A(Rolling
12-month historical returns relative to Sistema)
10Chile AFP Tracking Errors Fondo E(Rolling
12-month historical returns relative to Sistema)
11Risk and Expected Return Within a Portfolio
- Portfolio Theory begins with the recognition that
the total risk and expected return of a portfolio
are simple extensions of a few basic statistical
concepts. - The important insight that emerges is that the
risk characteristics of a portfolio become
distinct from those of the portfolios underlying
assets because of diversification. Consequently,
investors can only expect compensation for risk
that they cannot diversify away by holding a
broad-based portfolio of securities (i.e., the
systematic risk) - Expected Return of a Portfolio
- where wi is the percentage investment in the i-th
asset - Risk of a Portfolio
- Total Risk (Unsystematic Risk) (Systematic
Risk)
12Example of Portfolio Diversification Two-Asset
Portfolio
- Consider the risk and return characteristics of
two stock positions - Risk and Return of a 50-50 Portfolio
- E(Rp) (0.5)(5) (0.5)(6) 5.50
- and
- sp (.25)(64) (.25)(100) 2(.5)(.5)(8)(10)(.4
)1/2 7.55 - Note that the risk of the portfolio is lower than
that of either of the individual securities
13Another Two-Asset Class Example
14Example of a Three-Asset Portfolio
15Diversification and Portfolio Size Graphical
Interpretation
Total Risk
0.40
0.20
Systematic Risk
Portfolio Size
40
1
20
16Advanced Portfolio Risk Calculations
17Advanced Portfolio Risk Calculations (cont.)
18Advanced Portfolio Risk Calculations (cont.)
19Advanced Portfolio Risk Calculations (cont.)
20Example of Marginal Risk Contribution Calculations
21Dollar Allocation vs. Marginal Risk
ContributionUTIMCO - March 2007
22Fidelity Investments PRISM Risk-Tracking System
Chilean Pension System March 2004
23Chilean Sistema Risk Tracking Example (cont.)
24Chilean Sistema Risk Tracking Example (cont.)
25Notion of Downside Risk Measures
- As we have seen, the variance statistic is a
symmetric measure of risk in that it treats a
given deviation from the expected outcome the
same regardless of whether that deviation is
positive of negative. - We know, however, that risk-averse investors have
asymmetric profiles they consider only the
possibility of achieving outcomes that deliver
less than was originally expected as being truly
risky. Thus, using variance (or, equivalently,
standard deviation) to portray investor risk
attitudes may lead to incorrect portfolio
analysis whenever the underlying return
distribution is not symmetric. - Asymmetric return distributions commonly occur
when portfolios contain either explicit or
implicit derivative positions (e.g., using a put
option to provide portfolio insurance). - Consequently, a more appropriate way of capturing
statistically the subtleties of this dimension
must look beyond the variance measure.
26Notion of Downside Risk Measures (cont.)
- We will consider two alternative risk measures
(i) Semi-Variance, and (ii) Lower Partial Moments - Semi-Variance The semi-variance is calculated
in the same manner as the variance statistic, but
only the potential returns falling below the
expected return are used - Lower Partial Moment The lower partial moment
is the sum of the weighted deviations of each
potential outcome from a pre-specified threshold
level (t), where each deviation is then raised to
some exponential power (n). Like the
semi-variance, lower partial moments are
asymmetric risk measures in that they consider
information for only a portion of the return
distribution. The formula for this calculation
is given by
27Example of Downside Risk Measures
28Example of Downside Risk Measures (cont.)
29Example of Downside Risk Measures (cont.)
30Example of Downside Risk Measures (cont.)