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Risk Management Analytics

Portfolio
Risk Measures
Investment portfolios contain
multiple sources of risk. Some risks, like "systematic" or market risks are
taken intentionally with the expectation of a return premium.
Additional risk may be introduced into a portfolio as a result of a
portfolios actual asset allocation differing from the stated Policy target
weights. This allocation mismatch may increase or decrease a plan's
total risk, but it will always increase a funds tracking error vs. its stated
Policy Benchmark. Additional risks within a portfolio may be
attributable to what is commonly referred to as Benchmark Mismatch. This
risk results from the weighted average of the manager benchmarks within an
asset class differing (sometimes substantially) from the overall
asset class benchmark. The other remaining source of risk inherent in
many institutional portfolios is active management risk. Active management
risk is taken based on the belief that it will offer a return premium, or
Alpha, relative to a passive investment alternative.
The Wilshire Compass provides Risk Management
Summary Reports that allow fund sponsors to measure and better understand all
of these risks which are inherent in large institutional portfolios.
Shown below are samples of these reports along with a brief explanation of
the risks being depicted.
The below graphically illustrates a Sample Funds'
strategic asset allocation investment policy target weights and how those
allocations contribute to the Fund's systematic or market risk.
Interestingly in the example below, while public equity investments represent
60% of the portfolio by weight, they contribute over 95% of the Fund's total
systematic risk!

The top of the next page shows similar
information but this time it is based upon the funds "actual" asset
allocation as of a point in time. In addition the lower section of this
page
provides insight into all of the Fund's sources of Total Risk and Tracking
Error.

The third page of the report shows what the
actual allocation mismatches are, i.e. overweight non-US equity 5.0% and
underweight fixed income by 6.0% and the impact on both Total Risk and
Tracking Error.

The fourth page of the report provides a granular
view of
Benchmark Mismatch at both Total Risk, and Tracking Error level. Notice
how the totals of each of these graphs 1.68% and 1.82% ties back to the Page
2, Benchmark Mismatch for Total Risk and Tracking Error respectively.

The final page of the report provides details
regarding where the most active management risk is being taken.

Additional Risk
Measures
All
of the analytics within the Asset and Manager modules give users the
option of choosing one of three statistical risk measures: standard
deviation, downside risk, and target shortfall. The most commonly
used risk measure, standard deviation, reflects the degree to which
an individual value in a probability distribution tends to vary from
the mean of the distribution. Standard deviation can be thought of as
the average dispersion from the mean within an observed sample or
population. Since most capital market return series are approximately
normal or lognormally distributed over long time periods, standard
deviation provides a fairly good and understandable description of
return volatility over time.
The
graph below plots the return and standard deviation (risk level) of
several indexes over the ten-year period ended December 31, 2009.
Downside risk or
semivariance is a statistical measure, which considers only those
deviations that fall below the mean, and is important to investors
who are concerned only about returns that are below the average.
Intuitively, downside risk is a reasonable measure and some portfolio
theories have been developed using it. However, when return series
are normally distributed downside risk is proportional to variance.
In these cases, the downside risk measure provides no greater insight
as to the relative riskiness of different assets or portfolios than
does the more easily understood standard deviation measure.
The graph below, shows
the same indexes but uses semivariance as the risk measure. As can be
seen the relative relationships between the market indexes is similar using
both risk measures.

Target Shortfall
is a statistical risk measure calculated in a similar fashion to
downside risk. Whereas downside risk takes into account only those
observations that fall below the mean, the target shortfall risk
measure is concerned only with those observations which fall below
a user defined and specified return.
Excess
Risk Measures
Compass allows
users to analyze another form of risk known as relative or excess
risk. Excess risk is defined as the volatility of excess return which
is defined as the difference between the portfolio return and the
return of some pre-specified standard such as a market index or peer
group. Common measures of excess risk are Tracking Error and Residual
Risk. Tracking Error is defined as variability of the total difference in returns
between an index and a manager's portfolio and it reflects all risks
associated with an active investment strategy. Residual Risk is a
narrower concept and generally refers to that portion of tracking
error that is not correlated with the index.
Tracking Error
can be calculated using a number of different analytics in Compass.
The Manager Consistency graph shown below plots Excess Return and
Excess Risk (Tracking Error) for several Small-Cap Value equity managers
vs. the Wilshire Small Value Index.

Tracking Error
gives investors insights into the level of active management risk
being assumed by the investment manager. In the graph above, products
with lower
excess risk would be expected to track their
benchmark more closely. In contrast, the other products would not
be expected to track the index as closely given their higher Tracking Error.
Residual Risk
can be calculated in Compass using either the single factor CAPM
model or the multiple factor attribution model. The CAPM model uses a market
index as the sole factor while the multiple factor attribution model uses
several different style factors to calculate residual risk.
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