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Copyright Dave Klein. All Rights Reserved.
Turning Beta into Alpha – Credit-informed Tactical Asset
Allocation
Using Signals from the Credit Market to make Equity Investment Decisions
February 13, 2012
Honorary Mention from the
National Association of Active Investment Managers (NAAIM)
Wagner Award 2012
By
Dave Klein
Capital Context LLC
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 2
Table of Contents Introduction .................................................................................................................................................. 3
Timing the Equity Market Using Signals from the Credit Market ................................................................. 5
Implementation ............................................................................................................................................ 9
Results ......................................................................................................................................................... 13
Performance Metrics .................................................................................................................................. 18
Challenges ................................................................................................................................................... 21
Extending the Strategy ................................................................................................................................ 24
Conclusion ................................................................................................................................................... 27
Appendix 1 - Formulas ................................................................................................................................ 28
Stylized Default Probabilities .................................................................................................................. 28
Power Relationship ................................................................................................................................. 28
Appendix 2 –Equity Index Results ............................................................................................................... 29
Bibliography ................................................................................................................................................ 30
Data Sources ............................................................................................................................................... 30
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 3
Introduction1 Credit analysts are fond of saying that “credit anticipates and equity confirms.” In
other words, prices in the credit market reflect anticipated trends before being
reflected in stock market moves. Anticipation does not always lead to
confirmation, but corroboration is provided often enough to implement a
profitable Tactical Asset Allocation (TAA) strategy that outperforms a buy-and-
hold policy when standard performance metrics are considered. In fact, our
back-test of the strategy captures 54% of upside equity moves on a monthly
basis while only taking 13% of the downside. Additionally, the strategy can be
extended for use with other alpha-generating strategies and as a method to
achieve complementary portfolio goals such as capital preservation.
Until recently, it has been fashionable for institutional investors to dismiss TAA
with an efficient market argument. Why would TAA opportunities exist if the
market encompassed all available information? This is an especially important
question when investing at the index level. Nevertheless, lackluster equity
returns over the past decade coupled with gut-wrenching moves over the past
few years created a receptive environment for TAA strategies. Given a choice,
most investors would choose relative returns during bull markets and absolute
1 The author would like to express gratitude to Tim Backshall and Roderick MacLeod for their assistance and
guidance.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 4
returns during sideways and bear markets. The TAA strategy described here
attempts to deliver this performance profile by using signals from the credit
market to move in and out of equity investments.
Before outlining our particular strategy, a brief discussion of TAA is in order. TAA
is a dynamic investment strategy that adjusts asset allocations based on a
particular model. Models vary from looking at company fundamentals to
considering technical indicators such as moving averages. TAA complements
Strategic Asset Allocation (SAA) but does not replace it. Regardless of how a
particular approach is developed, any TAA strategy makes use of market-timing
signals with the goal of producing returns that outperform a benchmark on a risk-
adjusted basis. This is in contrast to SAA which sets a portfolio’s policy for how
funds are to be invested among different asset classes.
TAA must also be distinguished from other sources of active portfolio returns in
excess of holding a benchmark index. TAA alters the systematic risk of the
portfolio by overweighting or underweighting broad asset classes (equities,
bonds, commodities, etc.). Other active strategies can change the idiosyncratic
risk of a portfolio through individual security selection. A TAA strategy might lead
to a preference of a 60/40 stock/bond allocation over a 70/30 allocation in order
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 5
to underweight systematic equity risk. Within that 60% allocation, an investor
might choose a basket of single-name equities or invest in a particular actively-
managed equity mutual fund (or hedge fund) to take on idiosyncratic risk.
Timing the Equity Market Using Signals from the Credit Market The relationship between a firm’s debt and equity is well established. As the
market capitalization of a company rises, its credit risk (the risk of default on a
company’s debt) falls and vice versa. If a company’s credit risk rises, its market
cap will generally fall.2 Deciding on the appropriate capital structure of a firm is a
key task of management. If a company takes on too much debt, future earnings
may be swallowed by interest payments. If too little debt is issued, growth
opportunities may be missed.
For large firms with strong balance sheets, the link between credit and equity
performance is tenuous at best. When there is very little perceived chance of
credit distress, the two portions of the capital structure behave seemingly
independently. However, when a company’s debt trades with substantial credit
risk embedded in its price, the link strengthens. That is why high yield debt is
2 One notable exception to this is the case of a leveraged buyout (LBO) where most of a firm’s equity is converted
into debt at a premium.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 6
highly correlated with stock market returns. The debt becomes more “equity-
like” while the stock becomes much more sensitive to the company’s credit risk.
This debt-equity relationship can be exploited profitably at the level of individual
companies and forms the basis for one type of capital structure arbitrage. For
example, if a company’s credit is expected to outperform its equity, then a trade
can be constructed to buy debt and sell (short) stock. If the two securities do
move back into line, a profit can be made.
The debt-equity relationship can also be exploited at the level of the market as a
whole. Specifically, using a bond index and an equity index, a view can be formed
on whether equities are overpriced or underpriced relative to bonds. Exhibit 1
shows six months of the Bank of America/Merrill Lynch HY/B index OAS3 (for
simplicity, we’ll subsequently refer to this index as the HY/B) on the X-axis and
the Russell 2000 equity index on the Y-axis. Clearly, there is a lot of ‘noise’ in the
relationship, but when credit spreads rise (that is, risk goes up), stock prices tend
to fall.
3 OAS = Option-Adjusted Spread. OAS provides a measure of credit risk. A higher OAS indicates a riskier bond (or
collection of bonds in the case of an index like the HY/B).
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 7
Exhibit 1 – HY/B vs. Russell 2000, Source: Russell Investments, Bank of America We chose the Russell 2000 because small cap equities tend to be more sensitive
to the credit cycle. We chose the HY/B index as it provides a reasonably long
history and, with its focus on B-rated debt, provides a stronger signal for equities
than other high yield indices like the HY/B’s parent, the Bank of America/Merrill
Lynch High Yield Master II index. 4 We will show below that the signal from the
HY/B proves to be a good choice for the Russell 2000 as well as other indices like
the Russell 1000, S&P 500 and assorted growth and value indices.
4 Russell Equity Index data is available on Russell Investments web site:
http://www.russell.com/indexes/data/US_Equity/Russell_US_index_values.asp The Russell 2000 index values reported on the Russell Investments web site do not match values reported on other financial web sites, however their returns do. BAML HY/B Index data (and others) can be found at the St. Louis Federal Reserve’s Economic Data web site: http://research.stlouisfed.org/fred2/categories/22
3000
3100
3200
3300
3400
3500
3600
3700
3800
3900
4000
4% 5% 6% 7% 8%
Ru
sse
ll 2
00
0
BAML US High Yield B Index (OAS)
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 8
The strategy outlined in this paper can be summed up by the following two rules:
1. If equities are undervalued relative to corporate bonds, go long equities.
2. If equities are overvalued relative to corporate bonds, exit stock positions
and buy short-term Treasuries (or park your cash in a money market
fund).
We choose to switch to Treasuries rather than corporate bonds because the
strategy is based on the belief that the credit market provides an early warning
that all corporate markets are due to correct downward (or upward). We are
switching in and out of a risky asset class (equities) and a riskless asset
(Treasuries) based on a signal from a third risky asset class (bonds).
The ‘early-warning’ aspect of this approach is a key strength of the strategy. The
quantitative model is constructed from tradable securities whose prices are
available on a daily basis rather than fundamental or macroeconomic data that
are published less frequently. Additionally, extending the model by using credit
default swap (CDS) data enables intraday access to the indicator. There is no lag
to information being incorporated into the model. Furthermore, the strategy
does not rely on technical indicators like moving averages which recognize a
market top or bottom only after that threshold has been reached.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 9
Implementation As stated above, we use the Russell 2000 and HY/B as our equity and credit
indices respectively. In order to judge the relative value of the two indices, we
first convert the HY/B from spreads into default probabilities.5 When undertaking
similar work on single-name credits, we find it advantageous to work with default
probabilities to limit the dominance of higher spreads when calibrating model
parameters. Spreads can theoretically go to infinity, but default probabilities only
go to 100%.
Once we convert spreads to default probabilities, we select a lookback period for
our model. We find six months to be useful as it is a long enough time-period for
meaningful changes in both credit and equity to occur but it is short enough that
generally there is no need to correct for the business cycle or inflation.
After selecting the lookback period, we model equity fair value using a power
model.6 We are not modeling returns. Rather, we are modeling actual price levels
for the Russell 2000 and HY/B indices. There is an inverse relationship between
default probabilities and equity prices. As default probabilities rise, equity prices
go down. As default probabilities drop, equities go up. Exhibit 2 shows a plot of
equity prices against default probabilities. We recalculate model parameters each
5 See Appendix 1 for an explanation of converting spreads to default probabilities.
6 See Appendix 1 for an explanation of the power model.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 10
trading day for use on the next trading day. That is, out-of-sample empirical data
are used to make daily trading decisions.
Exhibit 2 – Default Probabilities vs. Russell 2000, Market Data: Russell Investments
When the current market levels of the Russell 2000 and HY/B are below the
relative value line, equities are cheap and we invest in equities. Above the line,
equities are expensive and we invest in short-term Treasuries.
3200
3300
3400
3500
3600
3700
3800
3900
4000
30% 32% 34% 36% 38% 40%
Ru
sse
ll 2
00
0
5Y Default Probability
Equities are Expensive -Hold Treasuries
Equities are Cheap - Hold Stocks
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 11
Exhibit 3 shows the Russell 2000 and our model’s fair value since July 1997.
Market and fair values tend to stay closely aligned with occasional exceptions.
Exhibit 3 – time series of index vs. fair value, Market Data: Russell Investments
Exhibit 4 charts the difference over the same period of fair value minus market
value. In Exhibit 4, a positive value indicates that equities are cheap (fair value is
higher than market) and a negative value indicates that equities are expensive
(fair value is less than market).
1000
1500
2000
2500
3000
3500
4000
Jul-97 Jul-00 Jul-03 Jul-06 Jul-09
Russell 2000 Market
Russell 2000 Fair
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 12
Exhibit 4 –Equity Disconnect over Time
-40%
-30%
-20%
-10%
0%
10%
20%
30%
Jul-97 Jul-00 Jul-03 Jul-06 Jul-09
Stocks are Cheap
Stocks are Expensive
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 13
Results Table 1 compares our credit-informed TAA strategy performance to a buy-and-
hold policy for the Russell 2000 from July 1, 1997 through December 30, 2011.
Daily returns were used to calculate the results. Over this period, the strategy
provides stellar results and a strong information ratio for the TAA strategy.7
Russell 2000 Strategy
Compound Annualized Growth Rate 5.8% 16.0%
Average Annualized Volatility 25.8% 17.9%
Sharpe Ratio (2.7%) 0.12 0.74
Information Ratio 0.49
Table 1 – Strategy Performance, July 1997 – December 2011
All results are calculated using daily closing values. Although, the current closing
values for the Russell 2000 and HY/B are not available until after market close,
values for the Russell 2000 are available throughout the trading day and it is
straightforward to use an intraday proxy for the HY/B to enable making a strategy
decision before market close. Further, performance actually improves over the
time period considered when opening values are used in conjunction with the
previous day’s signal.
7 The information ratio is defined as the excess return (strategy return – benchmark return) divided by the
standard deviation of the excess return. It provides a risk-adjusted measure of strategy performance. Positive numbers indicate outperformance.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 14
In our back-test, the strategy does a good job of limiting downside risk while
capturing a substantial portion of upside gain. Exhibit 5 charts the monthly
returns of the Russell 2000 (X-Axis) against the monthly returns of the strategy (Y-
Axis). Positive returns are represented by blue dots while negative returns are
represented by red dots. The black line indicates the level where strategy returns
match the market. Dots above the black line represent strategy outperformance
and dots below the line represent underperformance. Even though monthly
returns are shown, the strategy is traded on a daily basis.
Exhibit 5 - Comparison of Monthly Returns, Market Data: Russell Investment
-20%
-10%
0%
10%
20%
30%
40%
-30% -20% -10% 0% 10% 20%
Stra
tegy
Mo
nth
ly R
etu
rns
Russell 2000 Monthly Return (1997-2011)
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 15
Applying a linear regression to the red and blue scatter plots, we find the blue
trend line has a slope of 0.54, meaning, on average, the strategy picks up 54% of
any monthly gain. The red trend line has a slope of 0.13 which means the strategy
only takes on 13% of the downside when the index had a negative monthly
return.
This disconnect in returns is the essence of the strategy. If one is willing to give
up a sizable portion of the upside (46%), then one is protected from a much
larger portion of the downside (87%). In a strong bull market, the strategy will
underperform as the market rises month after month. In a sideways or declining
market, the strategy excels.
Exhibit 6 charts the portfolio value of $100 invested in both the strategy and the
Russell 2000 since July 1997. Transaction costs and taxes are ignored. $100
invested in the strategy in July 1997 would be worth over $850 at the end of
December 2011 compared to roughly $225 for buying and holding the Russell
2000.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 16
Exhibit 6 – Performance Results 1997-2011 (logarithmic scale), Market Data: Russell Investments
Moving from returns over the entire time period, Exhibit 7 considers 1 year (blue
line) and 5 year (red line) rolling excess returns. A positive number indicates the
strategy outperformed the index. The strategy does quite well over some periods
and underperforms during others, even over five years. On average, excess
returns are positive both over 1 year and 5 year time horizons.
100
1000
Jul-97 Jul-00 Jul-03 Jul-06 Jul-09
Russell 2000
Strategy
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 17
Exhibit 7 – 1Y and 5Y Excess Strategy Returns
The five year period from October 2002 to the market peak of October 2007
provides an example of how the strategy underperforms the overall market
during a strong bull market. During that period, the Russell 2000 rose by 143%
with 14.3% annualized volatility while the strategy gained 95% with 10%
annualized vol. Conversely, the period from November 2007 through September
2011 told quite a different story with the Russell 2000 losing 17.8% and the
strategy gaining 204% respectively.
-100%
-50%
0%
50%
100%
150%
200%
250%
300%
Jul-98 Jul-01 Jul-04 Jul-07 Jul-10
1 Year Excess Return
5 Year Excess Return
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 18
Performance Metrics It is not difficult to construct an investment strategy that does well, maybe even
spectacularly so, over a period of a year or two. To judge whether the strategy is
durable, it is useful to employ quantitative performance metrics.8 Table 2 lists the
results of five different measures based on 174 monthly returns (14.5 years). All
measures, except the hit ratio, indicate durable alpha (outperformance).
Measure Result
Geometric Average Alpha 9.6%
Arithmetic Average Alpha t-statistic 3.4
Information Ratio (monthly returns) 0.44
Hit Ratio 47%
Excess Skewness 2.1
Table 2 – Quantitative Performance Measures using Monthly Returns
Descriptions of each quantitative measurement are taken from Stockton &
Shtekhman.
Geometric Average Alpha is the difference between the geometric average
return of the strategy and the geometric average return of the benchmark (the
Russell 2000 in our case). A positive geometric average alpha indicates historical
8 Kimberly A. Stockton & Anatoly Shtekhman, A primer on tactical asset allocation strategy evaluation,
https://institutional.vanguard.com/iip/pdf/tacticalassetallocation_052006.pdf (July 2010)
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 19
outperformance. By this measure, the strategy outperformed the benchmark by
an impressive 9.6% annually.
Arithmetic Average Alpha t-statistic tests whether the average alpha
(outperformance) is different from zero. A value greater than 2, as is the case for
the strategy, indicates that outperformance can be expected in any given
investment period. The strategy’s t-statistic of 3.4 indicates that outperformance
is statistically significant.
Information Ratio is the ratio of alpha to the standard deviation of alpha (the
tracking error). It provides a measure of risk-adjusted return. An information
ratio of 0.44 indicates that the strategy outperformed the benchmark over the
period 1997-2011. It would not be placed in the top quartile of active returns.9
Still, for a ‘simple’ TAA strategy, an information ratio of 0.44 provides durable
alpha.
Hit Ratio is the proportion of times the strategy had positive alpha. Over 174
months, the strategy had positive alpha 82 times for a hit ratio of 47%. The
relatively low hit ratio is not surprising given that the strategy stayed fully
9 Grinold, Richard C. and Ronald N. Kahn, 2000. Active Portfolio Management: A Quantitative Approach for
Providing Superior Returns and Controlling Risk. New York: McGraw-Hill.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 20
invested in the market for 29 of the monthly periods. Looked at a different way,
the strategy meets or exceeds market performance 66% of the time.
In rough terms, over the past fourteen and a half years, the strategy
outperformed half of the months, performed in-line with the broader market a
sixth of the months and underperformed a third of the months. Additionally, the
hit ratio does not address the magnitude of the outperformance or
underperformance. The fact that the strategy captures 54% of the upside of the
benchmark and only 13% of the downside is perhaps a more compelling metric.10
Excess Skewness judges how positively skewed results are relative to the
benchmark. Over the time period considered, monthly strategy returns were
positively skewed while monthly benchmark returns were negatively skewed. One
way to view the skewness is that the strategy provides a greater opportunity for a
few big upside returns balanced by many returns just below the average. The
time series of returns appears to bear this out.
With the exception of the Hit Ratio, performance metrics all point to a TAA
strategy that has been effective over a time period of fourteen and a half years.
Past performance is, of course, no guarantee of future gains, but durable alpha
10
This type of analysis is in the spirit of the Merton-Henriksson timing test.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 21
provided by the strategy appears to be the result of more than just luck according
to these metrics.
Challenges While the TAA strategy outlined above adds value according to standard
performance metrics, it is not without its challenges both from an
implementation and psychological perspective.
Transaction Costs and Tax Issues - We perform our analysis of the strategy while
ignoring trading costs and tax issues. While tax issues can be muted in certain
situations, transaction costs are always present and will degrade relative
performance. Many individual investors may not be able to trade the strategy
efficiently as it requires daily monitoring and the movement into and out of
equities multiple times a year. Given the liquidity of the instruments traded,
institutional investors, and individuals with the ability to trade efficiently, should
be able to minimize transaction costs compared to trading a large basket of
individual equities.
Scalability - the strategy as presented requires switching from 100% equities to
100% risk-free asset and back and raises scalability issues. A more sophisticated
entry/exit policy should be able to capture much of the upside of the strategy and
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 22
eliminate some of the churn. Furthermore, the strategy can be implemented as
an overlay whereby a portfolio’s equity beta exposure is hedged, when
appropriate, via the use of equity index futures.
Disappearance of Arbitrage – any strategy is vulnerable to being a victim of its
own popularity. As more traders pile in, arbitrages disappear. This strategy is not
immune, but the fact that the relationship traded utilizes broad-based indices
should provide a measure of longevity to the opportunity. Additionally, the
motivation for the strategy is that credit investors are faced with different
mandates and liquidity constraints than equity investors. We do not expect this
difference to materially change in the future.
Psychological/Practical Barriers – the strategy, as is evidenced in Exhibit 4 above
can stay in or out of equities for extended periods of time. Imagine exiting
equities in December 1999, as recommended by the strategy, and not getting
back in for any meaningful period of time until February 2001. In February 2001,
you would be happy to have earned a risk-free return over the previous 14
months. You might have felt differently in March 2000 after sitting out 3 months
of a continued equity rally. It would take an extremely disciplined investment
manager to stick with the strategy in the face of an equity bubble.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 23
Data mining – as with any strategy for which long-run audited returns do not
exist, it is quite possible that the performance outlined is due more to data mining
than to strategy value. Despite whatever safeguards and care were used when
developing the back-test, knowledge of the past fourteen and a half years is
embedded in the strategy. At the most basic level, we have found modeling the
credit-equity relationship using a power model and a 6-month lookback to be
beneficial when developing trading strategies over the past few years.
An analysis of the sensitivity of TAA performance to the lookback period shows
the value of the six-month time period. Table 3 lists performance metrics for the
strategy when different lookback periods are used. Clearly, there is a benefit to
using a lookback period of at least six months. Whether this is a persistent
benefit is hard to tell with a back-test period of 14.5 years. As stated above, we
use a 6 month period in other empirical capital structure arbitrage research. The
intuition behind this (heuristic) choice is that 6 months is long enough to capture
a meaningful trading relationship but short enough to ignore macroeconomic
factors like inflation.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 24
3 Months 4 Months 5 Months 6 Months 7 Months 8 Months 9 Months
CAGR 13.7% 13.7% 13.7% 16.2% 14.8% 14.8% 14.8%
Average Annualized
Volatility
18.2% 18.2% 18.3% 18.0% 17.9% 17.8% 17.5%
Sharpe Ratio (2.7%) 0.60 0.61 0.60 0.75 0.68 0.68 0.69
Table 3 – Strategy Performance, October 1997 – December 2011 for Multiple Lookback Periods Short Back-test Time Period – while fourteen and a half years may seem like a
long time, it is short for evaluating the effectiveness of equity strategies.
Unfortunately, we do not have access to a longer time series of high-quality credit
data. However, the past fourteen and a half years encompassed multiple
economic cycles that included several bubbles and crashes. With that in mind,
strong performance metrics over the examined time period provide confidence in
the strategy.
Extending the Strategy The strategy outlined above provides robust results and is valuable on its own.
Still, more can be done to enhance and extend its value.
Refined Credit Index - While the HY/B provides a strong foundation for the TAA
model outlined, custom CDS indices can refine the strategy. At Capital Context,
we use a proprietary CDS index, the Capital Context Corporate Index (C3I), to
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 25
implement the TAA strategy.11 Use of CDS data enables us to track credit-equity
relative value throughout the trading day. Further, control over credit index
membership enables us to strengthen the credit signal for use in the strategy.
Index member selection and model implementation are beyond the scope of this
paper.
Multiple Equity Indices – Table 4 in Appendix 2 outlines performance
characteristics when the Russell 2000 strategy was applied to other equity indices
from July 1997 through December 2011. The same signal (from the Russell 2000-
HY/B relationship) was used for each index. Given the correlation of equity
returns, it is not surprising that the strategy can be deployed across a broad
spectrum of equity indices.
Portfolio Overlay – While strategic asset allocation provides diversification and
can lower a portfolio’s overall volatility, correlations across asset classes continue
to rise.12 With equity beta found in non-equity asset classes, implementing the
TAA strategy using highly-liquid equity futures enables broader portfolio
protection. We believe this is the true “killer app” for this type of TAA strategy
11
More information on our index (C3I) can be found at: http://capitalcontext.com/2011/09/21/introducing-the-capital-context-corporate-index/ 12
http://www.cboe.com/Institutional/JPMCrossAssetCorrelations.pdf
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 26
because it reduces portfolio churn while maintaining the expected benefits of
increased returns and lower volatility.
Combination with Other Alpha Strategies - The strategy outlined above attempts
to lower systematic risk while generating alpha. It can also be used as a signal to
be net long equities or to adopt a market-neutral stance (a long/flat strategy).
Given its inputs and implementation, the strategy tends to be uncorrelated with
other alpha signals. We find this lack of correlation to be valuable when
combining the TAA signal with other strategies.13 Indeed, the signal provides an
excellent complement to macro-economic & factor-based strategies since it is
purely based on market prices.
Foundation for Capital Preservation Strategy - The strategy also fits well with
capital preservation strategies. As Exhibit 5 illustrates, it provides an expected
payout somewhat similar to a call option. This provides a head start to hedging
strategies that limit downside risk by foregoing some upside profit. It also
delivers lower portfolio volatility without impacting expected returns.
13
While our work with partners cannot be discussed publicly, given its proprietary nature, an example of combining Capital Context’s TAA strategy with a momentum strategy can be found at: http://capitalcontext.com/2011/09/02/combining-credit-and-momentum-in-tactical-asset-allocation/
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 27
Conclusion The tactical asset allocation strategy outlined above lowers equity portfolio risk
while boosting overall returns. By its nature, it captures most of an equity
index’s upside return and greatly limits expected downside risk. Statistical
analysis of the strategy shows that an implementer can expect durable positive
alpha. Further, the strategy holds up well on its own but can also be extended for
use with other alpha strategies and to achieve complementary portfolio goals like
capital preservation. While there are barriers to successful implementation, the
strategy is worth the consideration of investors looking to manage equity beta
risk and traders looking for new sources of durable alpha.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 28
Appendix 1 - Formulas
Stylized Default Probabilities To convert spreads to default probabilities, we make a time to maturity assumption T and recovery rate
assumption RR. This yields a simple approximation of default probabilities from spreads of:
( ) ( )
( )
OAS is expressed in basis points (hence the division by 10,000). This ‘default probability’ is not intended
to be interpreted as a real probability, risk-neutral or otherwise. Simply, when modeling equities
relative to credit, high spreads tend to dominate. However, large changes in high spreads result in only
modest changes to default probabilities. In other words, this ‘stylized’ default probability provides a
useful ‘fiction’ when judging relative value across the capital structure.
For our analysis, we used a time to maturity of 5 years and recovery rate assumption of 40%.
Power Relationship To model equities against default probabilities, a simple power relationship is used.
defprob is a default probability calculated using the formulas above. Rather than using a linear
regression, A & B are constants calibrated from the trailing 6 months’ worth of time series data by
simultaneously minimizing the mean square error of both the estimated index value given a default
probability as well as the estimated default probability given an index value. In practice, linear
regression can be used to model
( ) ( )
with minor degradation of expected returns.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 29
Appendix 2 –Equity Index Results
The following table compares buying and holding a benchmark index against switching between the benchmark
and 3 month Treasuries over the period July 1, 1997 – December 30, 2011. The switching strategy is based on the
signal generated when comparing the Russell 2000 index to the ML/BA High Yield B index. All results were
calculated using daily returns.
Correlation to Russell
2000
CAGR Average Annualized Volatility
Sharpe Ratio Information Ratio
Index Index Strategy Index Strategy Index Strategy Strategy
S&P 500 0.88 2.4% 10.9% 21.6% 15.1% -0.01 0.55 0.52 Russell 1000 0.90 4.6% 12.0% 21.7% 15.1% 0.09 0.61 0.44 Russell 1000 Growth 0.87 3.3% 11.4% 23.3% 15.5% 0.03 0.56 0.43 Russell 1000 Value 0.86 5.2% 12.4% 21.6% 15.6% 0.12 0.62 0.44 Russell 2000 1.0 5.8% 16.0% 25.8% 17.9% 0.12 0.74 0.49 Russell 2000 Growth 0.98 3.8% 14.8% 27.9% 18.4% 0.04 0.66 0.48 Russell 2000 Value 0.97 7.3% 16.9% 24.7% 17.9% 0.18 0.80 0.51 Russell 3000 0.91 4.6% 12.3% 21.8% 15.2% 0.09 0.63 0.45 Russell 3000 Growth 0.89 3.3% 11.6% 23.4% 15.6% 0.03 0.57 0.44 Russell 3000 Value 0.88 5.3% 12.8% 21.7% 15.6% 0.12 0.64 0.46
Table 4 - Performance comparison of strategy vs. holding various indices.
Turning Beta into Alpha - Credit-informed Tactical Asset Allocation 30
Bibliography
Grinold, Richard C. and Ronald N. Kahn, 2000. Active Portfolio Management: A Quantitative Approach for Providing Superior Returns and Controlling Risk. New York: McGraw-Hill. Klein, David, June 2011, Credit-Informed Tactical Asset Allocation, working paper,
http://ssrn.com/abstract=1872163
Kolanovic, Marko, May 2011, Rise of Cross-Asset Correlations,
http://www.cboe.com/Institutional/JPMCrossAssetCorrelations.pdf
Lee, Wai, 2000, Theory and Methodology of Tactical Asset Allocation, John Wiley and Sons Stockton, Kimberly A. & Shtekhman, Anatoly, July 2010, A primer on tactical asset allocation strategy evaluation, https://institutional.vanguard.com/iip/pdf/tacticalassetallocation_052006.pdf
Data Sources Russell 2000 Equity Data – Russell Investments Web Site
http://www.russell.com/indexes/data/US_Equity/Russell_US_index_values.asp
Bank of America/Merrill Lynch High Yield B Index – Federal Reserve Bank of St.
Louis FRED Economic Data Web Site:
http://research.stlouisfed.org/fred2/categories/22
S&P 500 Equity Data – Yahoo! Finance:
http://finance.yahoo.com/q/hp?s=%5EGSPC+Historical+Prices