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Risk Horizon and Expected Market Returns
Georges Hubner∗† Thomas Lejeune ‡
October 2012
Abstract
The paper proposes an equilibrium asset pricing model that accounts of the incompleteinformation on returns distribution and investors’ preferences. As the model defines anintuitive risk measure (risk horizon) which relates to a time horizon, the horizon of treasurysecurities can be exploited to calibrate the parameters of the model. As a by-product, time-varying estimates of the expected return on the market portfolio are extracted and theirrelevance for stock returns predictability is tested.
JEL Classification: G11; G12; C14
∗Deloitte Chaired Professor of Portfolio Management and Performance, HEC Management School - Uni-versity of Liege, Belgium; Associate Professor, School of Economics and Business, Maastricht University, theNetherlands; Founder & Chief Scientific Officer, Gambit Financial Solutions Ltd, Belgium. Correspondingaddress. University of Liege, HEC Management School, Rue Louvrex 14 - N1, B-4000 Liege, Belgium. Phone:(+32) 42327428. E-mail: [email protected]†This research has been supported by the Dauphine-Amundi Chair in Asset Management. We wish to
thank Jan Annaert, Marie Briere and Michael Rockinger for helpful comments on previous partial versionsof the paper, participants to the 2012 annual workshop organized by the Amundi Asset Management Chairof Paris-Dauphine University, as well as seminar participants at HEC Montreal. The authors are grateful toDorothee Honhon for her invaluable contribution to an earlier version of this work. Financial support fromDeloitte (Belgium and Luxembourg) is gratefully acknowledged. All errors remaining are ours.‡FRS-FNRS Research Fellow, HEC Management School – University of Liege. E-mail:[email protected]
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1 Introduction
Asset pricing models provide insights into how the cross-sections of expected returns are
determined at equilibrium. Along the lines of the Capital Asset Pricing Model (CAPM)
introduced by Sharpe (1964), Lintner (1965) and Mossin (1966), individual security or port-
folio expected returns are often defined as a linear function to the expected return on a risky
fund, interpreted as the market portfolio. In the multiple use of traditional asset pricing
models, the expected market return becomes a key input in capital budgeting decisions, as-
set allocation and wealth projection. Consequently, the application of asset pricing formulas
for solving portfolio and corporate problems requires clean parameter values. Most model-
streat the expected market return as exogenous, and no clear guidelines are provided for its
estimation in practice.
In spite of the criticisms raised by Merton (1980), who suggests an exploratory method,
the estimation of expected returns based on the realized ones still remains the standard
(Mayfield, 2004). Realized returns are yet far from a perfect proxy as they are likely to
introduce large measurement error (Blume and Friend, 1973; Sharpe, 1978), to be influenced
by information surprises (Elton, 1999), to yield implausible implications for risk-aversion
(Mehra and Prescott, 1985), and to be biased due to potential learning effects (Lewellen and
Shanken, 2002). Another approach uses forward-looking estimates from analysts’ expecta-
tion measures or forecasts (Brav et al., 2005; Welch, 2000; Claus and Thomas, 2001). While
this approach seems more realistic due to its forward-looking aspect, it still relies upon the
assumption that analysts’ forecasts are representative of market-wide expectations, and do
not make use of market prices information.
Besides these reservations on the relevance of realized returns or forward-looking measures
for expected returns, these estimation approaches also lack of theoretical foundations. Our
paper overcomes these limits by tackling the issue of the expected market return estimation
inside an original asset pricing framework. The asset pricing model is based on an intuitive
risk measure, namely the notion of “risk horizon”, with reference to the time horizon required
for the convergence of a security’s mean return towards its expectation. Using standard re-
2
sults in the non-parametric statistical literature to characterize the risk horizon measure,
we relax many restrictive assumptions about return distributions or utility functions found
in traditional asset pricing models. The framework allows us to derive CAPM-like pricing
relationships. The model’s implications for market equilibrium provide the basis for the de-
termination of expected market portfolio returns. The originality of our approach lies in the
explicit inclusion of the term structure of interest rates within the equilibrium framework. As
the risk measure refers to a notion of time horizon, it can be matched with the risk horizon of
treasury securities whose expected returns are modelled by the yield curve. The framework
makes it then possible to use information contained in the term structure of interest rates
to calibrate the model parameters. Furthermore, through an arbitrage argument, an equi-
librium link between risk and return of Treasuries and the market portfolio can be exploited
and estimates of the expected return on the market portfolio can also be extracted.
This framework has the original advantage of providing an intuitive link between the
term structure of interest rates, the expected market portfolio and market-wide preferences
for asymmetric and fat-tail risks embedded in the risk horizon measure. Such a link is de-
sirable for several reasons. First, it is grounded on the theoretical basis of an asset pricing
framework that exploits the realistic view that entire return distribution and investors prefer-
ences are hardly observable, and only partial observation of moments of orders 2, 3 and 4 are
observed. To the extent that higher order moments are priced at equilibrium (Chunhachinda
et al., 1997; Harvey and Siddique, 2000; Fang and Lai, 1997; Dittmar, 2002), market percep-
tion of “moment risks” seems relevant to the estimation of expected market returns. Second,
term structure factors are shown to be good predictors of expected stock returns (Camp-
bell, 1987; Lettau and Wachter, 2009). Finally, if the market-wide attitudes towards risk is
a leading indicator of market sentiment, the ability to model the time-varying behavior of
their determinants will enable us to test new predictors of systemic market risks and assess
their relevance for pricing equity and interest-rate related securities.
In the empirical part of the paper, we propose applications of the risk horizon framework,
and use U.S. market data to calibrate the risk horizon parameters and the expected return
on the market portfolio. We find plausible parameters estimates with interesting cyclical
3
patterns in the time series of the expected return. The empirical relevance of these estimates
is examined with tests of statistical and economic predictive ability for stock excess returns.
The results provide some evidence on the added value of the parameter in out-of-sample
forecasts and asset allocation with respect to popular predictors found in the literature (see
a.o. Lettau and Ludvigson, 2001; Rapach and Wohar, 2006; Goyal and Welch, 2008).
The paper is structured as follows: Section 2 describes the model setup. Build on an
arbitrage argument, a system of equilibrium equations is derived in section 3, and relates
the market portfolio to the term structure of interest rates. The fourth section section
is dedicated to empirical applications, with parameters calibration on U.S. data and the
analysis of the predictive performance of the endogenously derived expected market return.
Section 5 concludes the article.
2 The Model
In this section, we describe the theoretical setup. We start with the set of assumptions re-
quired to construct the model around the risk horizon measure. A characterization of the
measure is then detailed with reference to standard results in the non-parametric statistical
literature.
2.1 Assumptions
Assume a set Ω of N + 1 risky assets indexed by i, and T periods, indexed by t. The first
set of assumptions that surrounds the model is identical to the CAPM framework: homoge-
nous assessment of returns distributions, lending and borrowing at a common continuously
compounded rate1, no transaction costs, all investors are price-takers and all securities are
infinitely divisible.
1The framework does not necessary require that this rate is riskless. Instead, a “least risky asset” (LRA),that is the asset whose horizon is lowest of all existing asset, can be used. Therefore, the use of risk horizon asrisk measure provide an interesting definition of what is traditionally meant as the risk-free rate, and allowsit to be stochastic.
4
The second set of assumptions differs from traditional framework, and weakens the strong
assumptions usually made on return distributions and utility functions. In the risk horizon
framework, they are replaced by the following assumptions.
Assumption 1: Periodic continuously compounded returns of each asset i for period t,
denoted Rit, are i.i.d. with unknown distribution. Only centered moments of orders 2 (µ2),
3 (µ3) and 4 (µ4) of the unconditional distribution of returns of any asset or portfolio i exist
and are known, and are denoted Vi, Si and Ki respectively.
This assumption is based on the realistic view that investors hardly observe the entire
probability distribution of asset returns, but might instead extract the information on the
riskiness of distribution with the use of measures of unconditional moments representing
volatility, asymmetry and fat-tailness. In this regard, Assumption 1 is therefore weaker than
traditional restrictions on returns distribution, as it only requires the existence2 and knowl-
edge of unconditional moments up to order 4. From period returns moments, it is easy to
derive the moments of the mean of a sequence of n drawings of these returns, Rn
i = 1n
∑nt=1 Rit.
They are equal to: V ni = Vi
n, Sni = Si
n2 , Kni = Ki
n3 +3(n−1)V 2
i
n3 .
Assumption 2: All agents are rational risk averters with unknown utility functions.
However, they consider that the risk horizon Hi of a security is the shortest number of
periods such that
P[RHii ≤ Ei − λ
]≤ (1− Λ) + γP
[RHii ≥ Ei + λ
](1)
for constants λ ≥ 0, 0 ≤ γ ≤ 1, 0 ≤ Λ ≤ 1 and where Ei is the expected return of the
security3.
Assumption 2 totally relaxes the traditional restriction on investors’ utility functions. It
replaces it by indirect information about investors’ preferences that is inferred from their
2Although the existence of these moments is a strong assumption regarding some evidence from manyseries of returns (see Jondeau and Rockinger, 1999), it is commonly used for the derivation of asset pricingmodels.
3If Hi is not an integer, it is implicitly assumed that time intervals can be divided through a factor z sothat the returns are still i.i.d. and the product zHi is an integer.
5
assessment of the riskiness of a security. By the weak law of large numbers, they know that
the mean return of a security converges in probability towards its expected value over an
infinite horizon of investment. However, for a finite number of periods, investors could con-
sider this convergence to be sufficient to make the mean not significantly different from the
expectation, and therefore to consider the security as approximately riskless. This number of
periods can be defined as the risk horizon and is formalized by equation (1): the probability
of the mean return falling short from a lower bound Ei − λ must be smaller than a constant
(1 − Λ) plus a premium. Parameter λ determines the boundaries of the convergence inter-
val, and therefore brings information on the market-wide aversion for extreme risks. The
higher the λ, the larger the interval required by investors, and the smaller the risk horizon
Hi for any given asset i, ceteris paribus. Parameter Λ depicts the tolerance level assigned
by investors such that the security i is considered as approximately riskless over an horizon
of investment Hi. The premium is composed of the potential of exceeding the upper bound
Ei + λ multiplied by a proportionality coefficient γ ∈ [0, 1]. This latter parameter can be
viewed as the market trade-off coefficient between the downside and upside potential of the
asset. If γ is close to 0, investors only care about downside risk: the risk horizon of a security
is just the number of periods necessary to respect a Value-at-Risk constraint. On the other
hand, if γ is large, investors assign a very high weight to the upside return potential of the
security. The limiting case γ = 1 implies that the market participants assign the same weight
to returns above Ei + λ than to returns below Ei + λ. In particular, for a security with a
symmetric distribution of returns, P[RHii ≥ Ei + λ
]= P
[RHii ≤ Ei − λ
]and the constraint
given by (1) is always respected, meaning that the risk horizon of this security is null.
The calibration of the market-wide parameters Λ, λ and γ cannot be done arbitrarily,
but should be endogenously derived at equilibrium. This problem is discussed in section 3
when the information on the term structure of interest rates is introduced. At this point,
investors’ perception of the riskiness of a security is characterized by equation (1) that makes
use of the probability distribution P, which was assumed to be unknown by Assumption 1.
Therefore, what is currently missing is a way to link the risk horizon definition (1) with the
set of available information, that is, moments of order 2, 3 and 4. This link is performed in
the next section where an analytical expression for the risk horizon is derived.
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2.2 Characterization of the risk horizon
Equation (1) formulates the way risk horizon is used to measure the riskiness of any security
or portfolio. However, as the entire return distribution is assumed to be unknown, an estimate
of the probabilities for the mean returns to exceed a certain interval around the expectation
needs to be provided in order to use the risk horizon measure and derive associated pricing
relationships. Chebyshev inequalities already provide such an estimate under the form of an
upper bound for the cumulative distribution, but are “much too wide” and do not exploit
the information of moments higher than 2. Mallows (1956) generalized Chebyshev-type of
boundaries to moments of order 3 and 4, and provide an attractive approach to estimate
the probability of mean convergence by using only the information assumed to be known.
Indeed, information given in Assumption 1 allows to adapt this classical result to derive an
expression for the risk horizon (All proofs are gathered in the Appendix):
Proposition 2.1 If Si and Ki exist and are known, the risk horizon of a security i is givenby:
Hi = min H : Λ ≤ 1− πi(−λ,H) + γπi(λ,H)
where πi(x,H) =∆i
Q2i (x) + ∆i(1 + Hx2
Vi)
Qi(x) = −Hx2
Vi+Six
V 2i
+ 1
∆i =1
H
(Ki
V 2i
− S2i
V 3i
− 3
)+ 2
under the constraints ∆i > 0
λ >1
2
(SiV H
+
√S2i
V 2H2+ 4
)and
∂πi(x,H)
∂ | x |< 0 ∀x
∂πi(x,H)
∂H< 0 ∀ϕi ≤ H ≤ Φi
where ϕi = min
[(−x2S2
i + S2i − ViKi − 3V 3
i x2 + 3V 3
i + ViKix2)2
4V 3i x
2S2i
,x2S2
i
V 3i (1− x2)2
]Φi = max
[(−x2S2
i + S2i − ViKi − 3V 3
i x2 + 3V 3
i + ViKix2)2
4V 3i x
2S2i
,x2S2
i
V 3i (1− x2)2
]
7
The probability function πi(x,H) represents the upper bound of the corresponding prob-
abilities defined in equation (1) and is function of the unconditional moments. One can
rewrite πi(x,H) = P(RH
i − Ei > x)
for x > 0 and P(RH
i − Ei < x)
for x < 0. Note the
behavior of πi with respect to x and H. The higher the interval x around expectations, the
greater the probability mass inside it, and the lower π. Moreover, the higher the risk horizon
H, the more concentrated the distribution around expectation and the lower the π.
Proposition 2.1 does not relate the risk horizon to the centered moments of the distri-
bution in any particular manner: H is not necessarily increasing in variance, decreasing in
skewness or increasing in kurtosis.4 Therefore, the risk horizon framework complies with
(Brockett and Kahane, 1992) critique as it does not posit any moment preferences.
3 Equilibrium relations with the yield curve
The upper bound π described above enables us to link investors’ common assessment of as-
set riskiness defined by equation (1) with the information about returns distribution that is
available to investors: the unconditional moments of order 2, 3 and 4. Beyond its implica-
tions for traditional market equilibria, a major added value of the model rests on its potential
use of the term structure of interest rates. Instead of introducing superfluous complexity,
information contained in interest rates can be exploited in order to ensure the consistency
of the model with a non-constant term structure. Because the notion of risk is related to a
measure of time horizon, it can be matched with the risk horizon of a riskless zero-coupon
bond (i.e. a treasury security). The yield of this security as a function of maturity is precisely
modelled by the curve of the term structure.
As in the CAPM, considering a unique equilibrium market portfolio5, the expected return
4Nevertheless, if only the second moment is observed, Proposition 2.1 collapses to the application ofChebyschev’s inequality, and risk horizon increases monotonically with the variance. Traditional mean-variance analysis is therefore nested into this framework.
5This constitutes an additional assumption to our framework, as Simkowitz and Beedles (1978) and Mittonand Vorkink (2007) show that diversification is not necessarily desirable due to skewness. In this paper, weneed to restore this principle to provide a consistent equilibrium with the term structure of interest rates.
8
of any security derives from the rate of return of the risk-free rate and the expected return of
the market portfolio. In most partial equilibrium models, the latter input is taken as exoge-
nous. However, thanks to information contained in the term structure, we can retrieve the
expected rate of return of the market portfolio. Furthermore, Assumption 2 posits that the
notion of risk is captured by expression (1) whose input parameters λ, γ and Λ are unknown.
All we need for the calibration of these parameters is a sufficient number of points on the
term structure. As treasury securities are priced at equilibrium, they have to satisfy this
assumption. Nevertheless, they cannot be treated as risky as they are totally riskless if they
are held until maturity. Therefore, some very risk averse investors are likely to hold them
without combining them with the market portfolio at equilibrium. Thanks to an arbitrage ar-
gument, these treasury securities must yield the highest expected return among all securities
with the same horizon as theirs. If, for instance, the expected rate of return of the treasury
security was lower that the optimal combination of the market portfolio and the least risky
asset – say, the short term Treasury Bill, it would be possible for any investor with the same
risk horizon to sell treasury securities to increase her position in the optimal combination.
This would induce an increase in the price of the optimal combination and a decrease in the
price of the treasury security up to the point where expected returns become equal.
Denote yτ the continuously compounded rate of return of a treasury security maturing
at τ . As for the risk-free rate Rf , the current yield-to-maturity of this security is equal to
its expected return over the next period, denoted Eτ . Its periodic future rate of return
is risky6 with its own moments Vτ , Sτ and Kτ . The treasury security is totally riskless if
held until maturity, but it can nevertheless be considered as approximately riskless for an
horizon of investment shorter than τ . Therefore, the risk horizon of such a security must
be equal to some time horizon Hτ = kτ with 0 ≤ k ≤ 1. In other words, any investment
in a riskless bullet bond whose horizon exceeds the one of the least risky asset will entail
a positive risk horizon, as for any other risky investment. With the help of a non-constant
term structure of interest rates, it is possible to endogenously derive the parameters k, λ, γ
and Λ, together with the expected return on the market portfolio (hereafter denoted Em),
6Of course, the pull-to-par phenomenon induces that debt returns are not stationary. Therefore, theargument only holds for a rolled-over portfolio of debt with a constant maturity.
9
following an arbitrage argument. This is done through a new fund separation theorem.
Proposition 3.1 If y = 1 and my ≡ m and if the term structure of interest rates obeys
a n-dimensional yield-factor model corresponding to maturities τ 1, ..., τn and risk horizons
Hτ1 , ..., Hτn, then the parameters Λ, γ, λ, k and the expected return on the market portfolio
Em are determined at equilibrium by solving the following system of equations:πτ j(−λ, kτ j)− γπτ j(λ, kτ j) = 1− Λ j = 1, ..., nπpj(−λ, kτ j)− γπpj(λ, kτ j) = 1− Λ j = 1, ..., nατ jEm + (1− ατ j)Rf = Eτ j j = 1, ..., n
(2)
where
Rpjt = ατ jRmt + (1− ατ j)Rft (3)
with m being the risky fund held at equilibrium. The equilibrium entails separation between
one risky fund and n treasury securities.
Note that the principle underlying this proposition is not easily transposable to other
asset pricing models. In our setup, risk is measured through a time period, which induces
that treasury securities are totally riskless for a given horizon (their maturity), and “ap-
proximately riskless” for their risk horizon. Therefore, they do not belong to the set of risky
securities. If another measure of risk were used (e.g. the variance of returns) these securities
could not be held as riskless for a given period of time as their returns would display some
variability.
Before we bring system (2) to the data, it is useful to examine its implications for the
endogenous expected market return. A closer examination of the bottom equations of the
system allows us to re-express the expected excess return on the market portfolio as follows:
Em − Rf =Eτj−Rfατj
, with this latter equation being required to hold for all Treasuries. This
decomposition emphasizes the presence of two components of Em in the model. The first one
is the expected return on Treasuries in excess of the risk-free asset (Eτ j − Rf ). It reflects
information contained in the term structure. The other component is the weight assigned by
investors on the market portfolio in the optimal risky portfolio. It is related to stock market
data, as it is influenced by the changes in statistical risk (moments) of the risky portfolio,
10
through the required matching between the risk horizon of this portfolio and the risk horizon
of treasury securities. As a result, periods of high riskiness (i.e. highly unfavourable Vm,
Sm and Km) apply a downward pressure to weights assigned to the market portfolio because
of this matching constraint. If the term structure is upward sloping, reduction in market
weights goes along with an increase in the expected excess return. This can be interpreted
as if investors perceive the high riskiness of the market but expect higher expected return
in the future, reflecting the anticipation of recovery from the information contained in the
positively sloped yield curve. In case of downward sloping curve (negative Eτ j − Rf ), the
expected excess return on the market portfolio decreases with lower weights (as we now have
Em − Rf < 0). The expected return Em might even turn negative if Eτ j − Rf is sufficiently
negative or in case of sufficiently low weights ατ j . This is consistent with the view that neg-
atively sloped yield curve indicates market anticipation of economic downturn (see a.o. Ang
et al., 2006) and investors expect negative market returns. On the other hand, if the mo-
ments riskiness is low, higher weights are allocated to the market portfolio, and the required
premium is closer to the treasury premium (Eτ j −Rf ). Our theoretical framework therefore
provides an intuitive link between the expected risk premium, the information contained
in the term structure, and “moments risks”. The exploitation of this link to calibrate risk
horizon parameters and the expected market return as well as its potential power for stock
return predictability is examined in the empirical application presented below.
4 Empirical application
Proposition 3.1 provides a framework that enables us to endogenously calibrate the param-
eters underlying the risk horizon measures and the expected return on the market portfolio.
In this section, we perform this calibration on U.S. market data. The framework has the
original characteristic of simultaneously linking market-wide risk premium estimates to the
term structure of interest rates which naturally refers to a notion of horizon risk, the aversion
for extreme risks, which is embedded in our measure of risk horizon through parameters λ
and Λ, and the market-wide aversion for asymmetric risks (parameter γ). This link is desir-
able for at least two reasons. First, it will enable us to discriminate the relative importance
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of asymmetric and fat-tail risks in market-wide risk premia, in a broader context than under
multi-moment models that only look at equity markets. Second, if the market-wide attitudes
towards risk is a leading indicator of market sentiment, the ability to model the time-varying
behavior of their determinants enables us to test new predictors of systemic market risks. In
particular, the relevance of information contained in the estimated expected return is verified
with tests of stock return forecasting ability and asset allocation applications. Our objective
is to analyse whether the endogenously calibrated risk premium reveals able to add statisti-
cally and economically significant value to forecasts from a model that already contains the
popular predictors found in the literature. We begin with the description of the dataset and
the methodology applied to these tests.
4.1 Data
We collect a sample of US monthly term structure factors from Gurkaynak et al. (2007) for
the period beginning in January 1980 until May 2010.We treat this sample with the Nel-
son and Siegel (1987) curve fitting model augmented by Svensson (1994) (hereafter NSS)
to retrieve US spot rates of required maturities. Table 1 reports some descriptive statistics
on NSS factors and US treasury rates and returns. Monthly returns of 1, 3, 5 and 10-year
treasury securities allow us to estimate Vτ , Sτ and Kτ needed to obtain the four functions
πτ in equation (2)7. Moments are computed on a 36 monthly return window8. Continuously
compounded returns of 3-month treasury security and logarithmic monthly total returns (in-
cluding reinvested dividends) of the S&P 500 index provide our estimates for Rf and Rm
respectively. Prices of the S&P 500 total return index are from the updated database of Goyal
and Welch (2008). It consists of month-end values from Center for Research and Security
Press (CRSP). Horizon Hτ is set equal to kDτ where Dτ is the Macaulay duration of US
Treasuries expressed in months and k a multiplier allowing for the possibility that Treasuries
might be considered as approximately riskless for an horizon lower than their maturities.
7As robustness check a system with only three treasury securities has also been implemented. Calibrationresults do not change significantly, except from the presence of more outliers, indicating less precise estimatesof our parameters.
8Similar results are obtained when longer calibration windows are considered in the model simulations,but the length of the estimation period is reduced. The accuracy of some parameter estimates appears todiminish (that is, they touch boundaries of the range of authorized values more often) when shorter calibrationwindows are used.
12
The expected return Eτ of each treasury security equals its corresponding NSS yield. The
time series of these yields are represented in figure 1.
Insert Table 1 and Figure 1 about here
In order to examine the relevance of the risk premium estimates, we implement some
in-sample and out-of-sample stock return forecasting tests and perform an asset allocation
application. In this analysis, the predictive power of our estimates is compared to other
popular predictors of stock returns. Most of the popular economic variables are collected
from the updated dataset of Goyal and Welch (2008)9:
1. Book-to-market ratio (btm): ratio of book value to market value for the Dow Jones
Industrial Average index.
2. Dividend payout ratio (de): logarithm of the ratio of a twelve-month moving sum
of dividends and a twelve-month moving sum of earnings.
3. Default spread (dfy): difference between the yields of BAA-rated and AAA-rated
corporate bonds.
4. Default returns (dfr): difference between the returns of BAA-rated and AAA-rated
corporate bonds.
5. Earnings-Price ratio (ep): logarithm of the ratio between a twelve-month moving
sum of earnings and S&P stock price.
6. Inflation (infl): log returns of the CPI (all urban consumers). Taking account of
delay in the release of the CPI index, we follow Goyal and Welch (2008) and use the
lagged series of this variable.
7. Long-term yield (lty): yield on long-term treasury bonds.
8. Long-term return (ltr): return on long-term treasury bonds.
9The description of the data and their sources are provided in Goyal and Welch (2008).
13
9. Net equity expansion (ntis): ratio of a twelve-month moving sum of net equity
issues by NYSE-listed stocks to the total end-of-year market capitalization of NYSE
stocks.
10. Stock variance (svar): monthly sum of squared daily returns on the S&P 500 index.
11. Term spread (tms): difference in yields between a long-term treasury bond and a
3-month t-bill.
In addition, we add the following variables as candidate predictors:
12. Business conditions (bus): the Aruoba-Diebold-Scotti indicator (from Aruoba et al.
(2009)), designed to track business conditions at high frequency and available on the
Philadelphia Fed website10. It mixes the low and high frequency seasonally adjusted
economic indicators whose release are closely watched by investors: weekly initial job-
less claims, monthly payroll employment, industrial production, personal income less
transfer payments, manufacturing and trade sales, and quarterly real GDP. Our vari-
able is centered around mean value so that positive values indicate better-than-average
business conditions, while negative values shows relatively worse-than-average condi-
tions.
13. Federal funds rate (ffr): the monetary policy rate collected on the website of the
Federal Reserve.
14. Market liquidity conditions (liqu): Pastor and Stambaugh (2003)’s liquidity fac-
tor is used for our liquidity component. Their aggregate measure is computed from
individual daily stock data and rely on the principle that order flows induce more im-
portant return reversals when liquidity is lower. Indicator values are typically negative
while larger in absolute magnitude when liquidity is lower.
In forecasting regressions, the dependent variable is the logarithmic total return on the
S&P 500 minus the logarithmic return on the three-month Treasury Bill. The summary
statistics of candidate predictors are described in Table 2. When needed, first differences or
detrending adjustments are applied to ensure stationarity.
10The Aruoba-Diebold-Scotti indicator is available at http://www.philadelphiafed.org/research-and-data/real-time-center/business-conditions-index/ .
14
Insert Table 2 about here
4.2 Calibration
Information contained in the term structure of interest rates allow us to endogenously extract
parameters k, λ, Λ, γ, as well as the expected market return Em and portfolio weights ατ .
To calibrate these parameters, the system of 12 equations with 9 unknowns described in
(2) is solved numerically11. Motivated by the theory, and to avoid unrealistic estimates, the
following set of constraints is applied:0 ≤ k ≤ 10 < λ ≤ 0.050 ≤ Λ ≤ 0.990 ≤ γ ≤ 10 ≤ ατ j ≤ 1
The upper bound for Λ of 0.99 means that investors require 99% of confidence in the
convergence of mean returns towards their expected value to consider an asset as approxi-
mately riskless. Constraints on parameter λ are rather lax with (monthly) asset mean returns
required to not falling out of a lower bound of 0.05 from expectations. Weights ατ are con-
strained between 0 and 1 so that no short sales are allowed12.
Due to the high non-linearities that characterize system (2), the simultaneous optimiza-
tion of the parameters is arduous. To overcome this difficulty, we apply a two-step iteration
approach to find the optimal values of the parameters at each date of our sample period. In
the first step, the risk horizon parameters (k, λ, Λ and γ) are kept fixed while only the weights
(ατ j) of the market portfolio and its expected return (Em) are allowed to vary. The weights
are then fixed to the optimized value found at the first step, and risk horizon parameters are
optimized in a second step. The expected return of the market portfolio (Em) is optimized
at each step. We then iterate between the two steps until the calibrated values converge.
At each date t, starting values comes from calibrated values in t − 113. Calibrated parame-
ters are reported in table 3. The time evolution of the estimates are displayed in figures 2 to 5.
11The SQP, Quasi-Newton algorithm implemented via the fmincon solver in Matlab is used in this task.12Results are robust to simulations with short sales allowed. Detailed results are available upon request.13This approach has shown to provide smoother estimates of the parameters compared to an approach
where all parameters are estimated simultaneously.
15
Insert Table 3 and Figures 2 till 6 about here
We start by considering the estimates of the risk horizon parameters (rows 1-4 in table
3). The estimates of the duration multiplier k are very close to 1, indicating that US Trea-
suries are perceived as approximately risk-free for an horizon close to their maturities. The
trade-off coefficient γ between downside and upside potential has a mean of 0.11 and display
infrequent jumps during the sample period. Estimates of λ imply that investors require, on
average, the distribution of mean returns to concentrate in the interval [−1%,+1%] around
their expectation on a monthly basis. The width of this interval is somehow compensated
by the calibrated values of Λ, which closely stick to the upper bound imposed. These results
derive from the matching of the risky portfolio with the risk horizon of Treasuries in system
(2). The difference in riskiness between Treasuries and the optimal portfolio is such that,
to respect this constraints, the model has to allow large intervals around expectations. The
recent financial crisis period (mid-2007 - 2010) provides extreme estimates. The sharp in-
crease in the riskiness of the market (reflected by its statistical moments) induces the model
to provide high λ and γ and reduce the weights of the market portfolio. However there is
a trade-off with multiplier k: as λ and γ reach high levels, the risk horizon constraint on
Treasuries becomes relatively lower and the model leads to choose a smaller risk horizon H
to reflect it, thereby reducing k. This explains the sharp decrease in k along with high levels
of λ and γ during this period. Such a behavior can be interpreted as the translation of the
“flight-to-quality” phenomenon in the model: a lower value of k corresponds to government
bonds being considered safe earlier.
The time series of the estimated weights are highly cyclical as depicted by figure 5.
Periods of small weights correspond to economic envrionments characterized by relatively
lower interest rates and higher uncertainty (higher volatility, more negative skewness and
higher kurtosis) on the stock market. During these periods, the model rests more heavily
on the risk-free asset to achieve low-yield, less risky objectives. As stressed in the discussion
of Proposition 3.1, the information conveyed by the weights influence the expected market
return Em. The estimates of Em have an annualized sample mean of 7.52% with an annualized
16
standard deviation of 0.77%. Figure 6 shows the time series evolution of Em and the 10-year
treasury yield. The difference between the expected value on the risky asset and the risk-
free treasury (denoted Em y10) is represented in green. This premium is characterized by
relatively low values in normal times (low premium over the 10-year yield) and high values
in crisis periods. Indeed, as discussed in the previous section, the expected excess return
on the market is closer to the treasury premium when market weights (α) are high, which
correspond to periods with relatively low market risk (favourable environment). In contrast,
periods of higher market risk are characterized by lower weights. Moreover, the yield curve
tends to flatten or inverse before important market downturns (see figure 1). This explains
the reduction and negative values of the the premium Em − y10 before NBER recessions
(represented in grey in figure 6). In the aftermath of downturns, we observe higher values for
Em as the yield curve returns to an upward-sloping shape and the weights stay at relatively
low values. The predictive power of this cyclical behavior in the estimated premium Em−y10
for stock returns is analyzed in the next section.
4.3 Predictive performance
We now investigate the predictive power of our premium estimates. In-sample and out-of-
sample tests are performed along the lines of the work of Rapach and Wohar (2006) and
Goyal and Welch (2008). In regressions, the dependent variable is the log total return on
the S&P 500 index minus the log return on a risk-free Treasury Bill. Using the financial
variables described above, we examine the predictive power of multivariate regressions for
stock returns. This analysis aims to produce forecasts from a model with and without
the premium estimate (Em − y10), and to investigate the statistical as well as economic
significance of this new variable.
4.3.1 Statistical predictive performance
The predictive ability is assessed by traditional statistics: root mean squared error of the
prediction (RMSE), cumulative squared prediction errors, Theil’s U and the Diebold and
Mariano (1995) and West (1996) statistic, adjusted by Clark and West (2007), for comparing
nested model forecasts (MSPE). This last statistic is used to test the null hypothesis that
an unrestricted model forecast is equivalent to a restricted model forecast, against the one-
17
sided (upper tail) alternative that the unrestricted model forecasts better than the restricted
model. Clark and West (2007) show that the traditional statistic needs to be adjusted to take
account of the noise in forecasts of the unrestricted model introduced by coefficients whose
population values are zero. They also show that their adjusted statistic has an asymptotic
distribution well approximated by the standard normal, so that one-sided critical values from
the standard normal distribution can be used (i.e. 1.282 for significance at 10% or 1.645 for
5%). The in-sample and out-of-sample forecasts are compared to the unconditional historical
mean. The period from Jan 1983 to Dec 1991 is used as the starting calibration period for
out-of-sample forecasts. Once a forecasts has been made in t + 1, the calibration period is
extended with the information available on t + 1 to produce the forecasts of period t + 2,
and so on. Out-of-sample forecasts of the unconditional model are generated using the mean
that prevails over each calibration period.
Several models are used to test the predictive ability of our estimate. First we consider in-
dividual regressions, where only the lags of the premium estimate (Em − y10) are introduced
as regressors. We then include these lags in multivariate regressions along with popular
financial predictors, and examine the predictive added value of (Em − y10). An intercept
is included in all regressions. The predictive power of first differences of our estimates is
also tested in separate models. Two types of lag structure are considered. In a first step,
regressors enter regressions with one lag. Regressions with this lag structure are reported
as models of type A. In a second analysis, a recursive model selection similar to the one
described in Pesaran and Timmermann (1995) is performed to retain the lag structure with
the best predictive power. This lag selection approach yields “type B”-models. To obtain
a relatively parsimonious specification and avoid potential over-fitting issues, we follow a
general-to-specific approach. Starting with 12 lags for each variables (i.e. 1 year), in-sample
criteria (adjusted R2, AIC and BIC statistics) are used to select the most relevant lag struc-
ture of each variable. The joint irrelevance of the dropped lags and variables are controlled
with F-tests. This model selection is recursive, as it is applied at each forecasting date. It
is therefore consistent with the use of information available in real time. For information,
regressions performed on the overall period are reported in table 4. Model B1 only include
traditional predictors and reports an adjusted R2 of 9.6%. Models B2 to B5 consider different
18
lags of the estimated (Em − y10) and display an adjusted R2 around 11.5%. For comparison
purposes, we also include model B6 and B7 that contain only lags of (Em − y10).
Insert Table 4 about here
Table 5 reports the different models along with their lag structure and their forecasting
performance. The first three columns provide information on the lag structure of the finan-
cial variables (first column), the premium (second column) and its difference (third column)
respectively. The next columns summarize information on in-sample and out-of-sample fore-
casts. The last two columns summarize the comparative performance of the specifications.
They report the MSPE test statistic for a comparison of the models and the unconditional
regression (before last column) and the models of the same type with financial variables only
(last column). The upper panel of the table reports the forecasting statistics of the uncondi-
tional model (historical mean only), and the other two panels are dedicated to the regression
models of type A (medium panel) and B (lower panel).
Insert Table 5 about here
In-sample tests are conducted with forecasts computed over the overall sample period,
from Jan 1983 to May 2010. All type A models have in-sample performance very close to the
unconditional model. Only model A3 and A5 marginally reduce the RMSE statistics with
respect to the historical mean predictions. If we select optimal lags for the financial variables
(model B1), the in-sample RMSE criterion is slightly better. Adding the optimal lags of our
premium estimates or its first difference brings a marginal improvement over other popular
predictors. However, significant differences can be observed in out-of-sample forecasts. While
forecasts of type A models do not statistically differ from the predictions of the unconditional
model, models A4 and A5, that only includes first lag of (Em − y10) or its first differences,
reach statistically better accuracy than their peers. This is underlined by lower RMSE and
significant MSPE statistic from the test of better forecasting ability with respect to model
A1.
19
When optimal lags are selected, the forecasts are improved when compared to the un-
conditional model, as can be observed from statistics of type B models. The MSPE test
statistics indicate that all the models inside this class perform statistically better than the
unconditional model in terms of out-of-sample predictions. Figure 7 reports the cumulative
sum of the squared error of out-of-sample predictions from prevailing historical mean minus
the cumulative sum of squared errors of model B1. An increase in this difference indicates
better performance of the latter. The cumulative difference indicates that the overall out-
of-sample improvements of popular predictors is especially important in periods of market
downturns, indicated in grey on the figure. Models of type B that include the optimal lags
of our premium estimates seem to deliver more accurate forecasts than model B1, as the
significant MSPE statistics in the last column of table 5 reports. The premium estimate
(Em − y10) seems to deliver some predictive ability that is not contained in popular predictors
found in the literature, and is therefore complementary to those predictors. Figures 8 and 9
display the cumulative performance for model B2 and B3 respectively.
Insert Figures 7 till 10 about here
In particular, the parsimonious models with the optimal lags of (Em − y10), namely (B6)
or its first difference (B7) alone, also display a positive and significant MSPE statistics de-
spite higher out-of-sample RMSE than model B1. Figure 10 shows that this higher RMSE
comes mostly from less accurate predictions during the recent financial downturn period.
While model B6 seems to exhibit more accurate forecasts during periods of normal times or
expansion, its performance during the 2007-08 financial crisis brings the cumulative difference
towards negative area. This observation is confirmed in sub-period analyses performed in
tables 6 and 7. These tables report the in-sample and out-of-sample forecasting performance
of the different models in periods of normal or bullish markets (table 6) and during periods
of bearish markets (table 7). Bearish markets periods are measured as the top 3 drawdown
periods in the price evolution of the S&P 500 total return index, and covers recent finan-
cial crises (LTCM crisis in July and August 1998, internet bubble from September 2000 to
February 2003 and recent subprime turmoil from December 2007 to February 2009). During
normal and bullish times, models of type-B that includes our premium estimates seems to
20
provide better forecasts with statistically significant MSPE statistics over both the uncon-
ditional model and models with popular predictors only. Over bearish market periods, the
complementarity of our premium estimates is less obvious, with no statistically significant
MSPE statistic when compared to a traditional model with popular predictors.
Insert Tables 6 and 7 about here
4.3.2 Economic predictive performance
In addition to the tests of statistical significance of the premium forecasts, we also conduct
an asset allocation application to examine their economic significance. In this application,
a self-financing portfolio is built and re-balanced according to premium out-of-sample fore-
casts. The portfolio consists in a market portfolio invested in the S&P 500 index (Rm) and
a risk-free asset (return on a Treasury Bill, Rf ). The monthly rebalancing of this portfolio
starts in Jan 1992 and ends in May 2010, and is based on the following trading rule: when-
ever the model predicts a significant negative equity premium, the portfolio takes a short
position in Rm and a long position in Rf . Otherwise, the portfolio stays long in (Rm −Rf ).
From our simulations, we test different thresholds to determine the significance of negative
forecasts. Only forecasts lower than these thresholds are considered as (economically) sig-
nificantly negative, and imply a rebalancing. The actual returns generated by this strategy
are then computed and compared to the performance of a passive strategy that stays long
in (Rm −Rf ) during the period. The results are also compared with returns generated by
forecasts from other models, and reported in table 8. Results are reported for a threshold
of 0bps and −30bps. Two Jobson and Korkie (1981) statistics for significant differences in
Sharpe ratio are also reported14. The first statistic tests the relative performance between an
active and a passive strategy, while the second compares the performance between models
14The formula for Jobson and Korkie (1981) statistic for testing the Sharpe ratio difference between twodifferent securities or portfolios is as follows:
zJK =s1 − s2√
θ
where
si =µi
σi
21
with or without the premium (Em − y10) (i.e. model B1 versus model B2).
Insert Table 8 about here
Over the entire out-of-sample period (upper panel in table 8), the portfolio performance
under active strategies outperforms the passive strategy results in terms of cumulative total
returns. These results are confirmed from the graph of cumulative returns of the different
strategies (figure 11). The early 2000’s and the 2007-08 financial turmoil is characterized by
a sharp decrease in the passive strategy, while strategies based on out-of-sample forecasts of
models of type B generate stable or even increasing returns during these periods. This better
performance comes mostly from the opportunity to rebalance the portfolio during downturn
periods. The active strategies display positive returns and significantly improve the Sharpe
ratio during these periods. The out-performance is reinforced once we select a lower threshold
to determine significant negative predictions. Moreover, forecasts from model B2 with esti-
mates of (Em − y10) improve the cumulative performance in each sub-sample period, when
compared to model B1 where the premium is excluded. The difference in Sharpe ratios turns
out to be statistically significant over both normal or bullish markets and periods of market
downturn.
Insert Figure 11 about here
To sum up, the tests of predictive performance reveal some forecasting ability of our
endogenously derived premium (Em − y10). This ability appears to bring some added value
with respect to other popular candidate predictors presented in the literature, with significant
out-performance when the premium is added to a complete model. The statistical out-
performance comes from more accurate out-of-sample predictions of the equity premium. An
for i = 1, 2 is the estimated Sharpe ratio and
θ = T−1[2− 2ρ1,2 +
1
2
(s21 + s22 − 2s1s2ρ
21,2
)]is the estimated variance of the difference in Sharpe ratios. The correlation between returns of portfolio 1and 2 is denoted by ρ1,2.
22
asset allocation application indicates better cumulative performance and Sharpe ratios when
these forecasts are used to rebalance the positions in a portfolio composed of a market index
and a risk-free asset.
23
5 Conclusion
The paper analyses the link between market expected returns, the information contained
term structure of interest rates and market-wide preferences for volatility, asymmetric and
fat-tail risks. We adopt an intuitive, non-parametric approach to associate the notion of risk
to a holding period that is necessary for the mean returns of a portfolio to be considered as
riskless. As the risk measure (risk horizon) provided by this model refers to a time horizon,
it is possible to characterize a system of equilibrium equations used to calibrate model pa-
rameters and the expected market return.
When the model is taken to the U.S. market data, we find economically significant es-
timates of the risk horizon parameters and the expected market return. Using forecasting
tests and asset allocation simulation, we show that the estimated expected return exhibits
some predictive power for the equity premium, and add value to popular predictors of the
equity premium found in the literature.
The extraction of such an assessment of expected market returns has interesting implica-
tions for future research. For instance, a general multi-moment asset pricing model can be
developed and tested with our estimates of expected market returns. Again, the risk hori-
zon framework seems appropriate as it does not rely on traditional restrictive assumptions
on either the returs distribution or utility functions and complies with both Simkowitz and
Beedles (1978) and Brockett and Kahane (1992) critiques. Another potential application
concerns portfolio allocation application. The assessment of portfolio optimal allocations ex-
tracted from the optimization based on investor’s desire to maximize expected return under
risk horizon constraints is possible within our framework. Several risk profiles can be covered
by varying the model parameters, and allocation could be compared to traditional objective
functions.
24
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6 Appendix
6.1 Proofs
Proof of Proposition 2.1
See Mallows (1956) using the moments of RH
i . The signs of the derivative with respect
to | x | is straightforward. The sign of the second derivative can be obtained by using the
variable transformation y =√Hx√Vi
and noting that dπi(y,H)dH
= ∂πi(y,H)∂y
dydH
+ ∂πi(y,H)∂H
. The first
term is always strictly negative and the second term is nonpositive for ϕi ≤ H ≤ Φi, which
completes the proof.
Proof of Proposition 3.1
The first line of the system corresponds to the definition of the risk horizon applied to
each treasury security. The second and third set represent the horizon risk and expected
return of a portfolio constructed only with a combination of the least risky asset and the
market portfolio. The second set of equation entails that each portfolio has the same risk
as the corresponding treasury security, while the thrid set of equation equates expected re-
turns. As each portfolio pk is mean-horizon efficient, by arbitrage, each treasury security is
mean-horizon efficient as well. The calibration of λ, γ, Λ and Em follows from solving the
nonlinear system of equations.
27
6.2 Tables
Table 1: Summary statistics of US term structure factors and zero Treasuries for the periodJan 1980 to May 2010.
NSS param. Mean Median min Max Std
Level (in %) 6,12 4,43 0,00 25,00 5,79Slope (in %) -0,71 0,10 -20,13 7,78 4,88Curvature 1 -1,61 0,00 -6,31 0,93 2,75Curvature 2 1,67 0,15 -1,00 6,27 2,70λ1 (1st hump) 0,03 0,02 0,00 0,24 0,03λ2 (2nd hump) 0,09 0,09 0,00 0,99 0,08
Mkt Data (in %) Mean Median Std Skewn. Ex. Kurt.
y1 5,91 5,56 3,41 0,63 0,24y3 6,40 5,88 3,23 0,59 -0,16y5 6,73 6,16 3,05 0,64 -0,29y10 7,27 6,58 2,74 0,74 -0,36R1 6,57 5,64 1,99 2,58 16,30R3 7,90 7,16 4,69 0,87 8,42R5 8,82 8,54 6,98 0,33 3,31R10 10,35 10,52 12,49 0,35 2,28Rf 5,79 5,40 1,09 1,46 3,93Rm 10,43 15,95 15,69 -0,94 3,36
Notes: The Nelson-Siegel-Svensson model (NSS) is used to retrieve the US spot rates using factors
from Gurkaynak et al. (2007). Level, Slope, Curvature 1 and 2 are NSS factors β0, β1, β2 and
β3, respectively in Gurkaynak et al. (2007). Factors λ1 and λ2 are parameters that determine
the location of the two humps in the term structure maturity span. Prices of hypothetical zero
Treasuries are computed according to the following formula: Pm,t = 100e−ym,tm12 where ym,t is the
US spot rate with maturity m expressed in annual terms. Logarithmic monthly returns (represented
by R in the table) are computed from these prices: Rt = ln(Pm−1,t
Pm,t
). Rm is the logarithmic period
return of the S&P 500 total return index. Rf is the continuously compounded return on 3-month
US T-bill. All yields and returns are here reported in annual terms.
28
Table 2: Descriptive statistics of the candidate predictors, period from Jan 1983 to May2010.
Overall period Expansions Recessions
Mean Std. Dev. Mean Std. Dev. Mean Std. Dev.btm 0,353 0,170 0,373 0,172 0,229 0,083bus -0,090 0,760 0,072 0,562 -1,065 1,026de -0,730 0,398 -0,753 0,382 -0,588 0,462
dfy 0,010 0,004 0,010 0,004 0,013 0,007dfr -0,0002 0,015 0,0002 0,013 -0,003 0,023dp -3,756 0,394 -3,706 0,385 -4,059 0,305ep -3,026 0,432 -2,952 0,406 -3,471 0,293ffr 4,986 2,591 5,351 2,524 2,798 1,807
infl 0,002 0,003 0,003 0,003 0,001 0,005liqu -0,026 0,069 -0,019 0,060 -0,068 0,100lty 0,070 0,022 0,073 0,022 0,051 0,007ltr 0,008 0,030 0,008 0,028 0,010 0,039
ntis 0,006 0,022 0,008 0,019 -0,004 0,030svar 0,003 0,005 0,002 0,004 0,007 0,010tms 0,024 0,013 0,023 0,013 0,027 0,013
Notes: Most of the dataset is collected from Goyal and Welch (2008). Refer to the text for names
and description of the different variables. Variables bus (Business conditions indicator), ffr (Federal
funds rate) and liqu (Pastor and Stambaugh (2003) liquidity measure) have been added. The overall
period considered extends from Jan 1983 to May 2010 and corresponds to the estimation period
of risk horizon parameters. Recessions dates are 1998:07-08, 2000:09-2003:02, and 2007:12-2009:02
and correspond to the top 3 drawdown periods in the S&P 500 index.
29
Table 3: Summary statistics of the risk horizon parameter estimates over the period startingin Jan 1983 to May 2010.
Mean Median min Max Std. Skewn. Ex. kurt.
k 0.924 1.000 0.012 1.000 0.237 -3.323 9.441λ 0.011 0.008 0.004 0.050 0.008 3.070 10.743Λ 0.990 0.990 0.990 0.990 0.000 -1.005 -2.012γ 0.111 0.000 0.000 0.974 0.253 2.211 3.552
ατ1 0.239 0.219 0.000 0.502 0.113 0.289 -0.712ατ3 0.413 0.383 0.117 0.726 0.173 0.224 -1.239ατ5 0.531 0.496 0.172 0.931 0.216 0.206 -1.253ατ10 0.712 0.705 0.273 1.000 0.247 -0.112 -1.453
Em (in %) 7.515 7.177 -1.544 13.708 0.767 -0.039 -0.034Em −Rf (in %) 2.762 3.117 -9.075 12.397 1.393 1.748 -0.303Em − y1 (in %) 2.323 1.698 -6.278 12.320 0.835 1.266 2.446Em − y10 (in %) 1.044 1.025 -6.921 8.682 0.929 3.083 -0.083
Correlations
Em y1 y10 Em − y1 Em − y101 -0.204 0.237 0.839 0.886 Em
1 0.731 -0.704 -0.552 y11 -0.234 -0.240 y10
1 0.950 Em − y11 Em − y10
Notes: Risk Horizon parameters are represented in the top 4 rows of the table: k, λ,Λ and γ. ατ iis the weight associated to the market in the portfolio with same risk horizon and expected return
that a Treasury with maturity τ i. Estimates of expected return Em and yields information are
expressed in annual terms.
30
Table 4: Regression results for models of type B, with an optimal lag structure selected basedon in-sample criteria. Standard errors are in parentheses. * indicates significance at the 10percent level. ** indicates significance at the 5 percent level. *** indicates significance atthe 1 percent level.
B1 B2 B3 B4 B5 B6 B7
const -0.0123* -0.0116* -0.0112* -0.0130* -0.0114* 0.00367 0.00424(0.00655) (0.00679) (0.00672) (0.00725) (0.00656) (0.00304) (0.00267)
dfy(-5) 6.32** 7.12** 7.11** 7.20** 7.25**(2.37) (2.11) (2.11) (1.95) (2.11)
dfy(-6) -4.38** -5.22** -5.28** -5.11** -5.39**(2.07) (1.80) (1.80) (1.79) (1.87)
ep(-2) 0.0713** 0.0781** 0.0751** 0.0728** 0.0758**(0.0309) (0.0317) (0.0306) (0.0310) (0.0289)
ep(-7) -0.0657** -0.0675** -0.0724** -0.0695** -0.0717**(0.0234) (0.0246) (0.0217) (0.0243) (0.0225)
ffr(-9) 0.0220** 0.0209** 0.0204** 0.0210** 0.0217**(0.00952) (0.0101) (0.00992) (0.0100) (0.0103)
lty(-1) -0.724** -0.762** -0.748** -0.719** -0.736**(0.280) (0.291) (0.284) (0.292) (0.290)
ntis(-2) -1.29** -1.35** -1.36** -1.20** -1.26**(0.576) (0.593) (0.595) (0.581) (0.592)
ntis(-3) 1.46** 1.52** 1.52** 1.39** 1.41**(0.586) (0.603) (0.607) (0.594) (0.596)
svar(-1) -1.42** -1.49** -1.48** -1.53** -1.51**(0.301) (0.281) (0.279) (0.278) (0.275)
(Em − y10)(−10) 6.10** 6.36** 6.09**(2.18) (2.19) (2.03)
(Em − y10)(−11) -6.83** -6.85** -4.89**(1.77) (1.73) (2.16)
d(Em − y10)(−10) 6.46** 5.84** 5.55**(1.80) (1.89) (1.89)
d(Em − y10)(−11) -2.44(1.67)
(Em − y10)(−1) -2.32(2.03)
(Em − y10)(−2) 1.53(3.04)
d(Em − y10)(−1) -1.70(1.99)
d(Em − y10)(−2) 0.528(2.24)
n 319 318 318 318 317 318 318Adj.R2 0.096 0.116 0.118 0.113 0.115 0.014 0.015
lnL 556 558 558 559 557 536 536
31
Tab
le5:
Sta
tist
ical
pre
dic
tive
per
form
ance
test
s:re
sult
sof
in-s
ample
and
out-
of-s
ample
fore
cast
ing
test
s.
Lag
stru
ctu
reIn
-sam
ple
perf
orm
an
ce
Ou
t-of-
sam
ple
perf
orm
an
ce
Fin
anci
als
Em−y 1
0d
iff(E
m−y 1
0)
RM
SE
Th
eil’
sU
RM
SE
Th
eil’
sU
MS
PE
MS
PE
stat.
vs
Ust
at.
vs
Fin
.Uncond.Model
Un
on
on
o44
8.19
1.00
431.
921.
00
TypeA
A1
firs
tla
gn
on
o44
9.62
1.00
470.
771.
090.6
6A
2fi
rst
lag
firs
tla
gn
o44
8.78
1.00
475.
241.
10
0.5
9-1
.53
A3
firs
tla
gn
ofi
rst
lag
447.
961.
0047
1.45
1.09
0.6
40.0
7A
4n
ofi
rst
lag
no
448.
741.
0043
5.82
1.01
-1.0
93.37
A5
no
no
firs
tla
g44
8.04
1.00
433.
351.
00
-0.8
83.34
TypeB
B1
opti
m.
lags
no
no
427.
080.
9541
3.05
0.96
2.34
B2
opti
m.
lags
10,1
1n
o42
2.13
0.94
408.
490.
952.75
1.94
B3
opti
m.
lags
no
1042
2.14
0.94
406.
480.
94
2.82
2.01
B4
opti
m.
lags
1,2,
10,1
1n
o42
1.86
0.94
413.
410.
962.52
1.2
7B
5op
tim
.la
gsn
o1,
2,10
,11
421.
850.
9441
1.86
0.95
2.57
1.3
7B
6n
o10
,11
no
448.
391.
0043
0.97
1.00
1.4
01.4
2B
7n
on
o10
448.
591.
0042
8.82
0.99
1.5
61.4
6
Notes:
In-s
amp
lep
erio
dco
rres
pon
ds
toth
eov
eral
lca
lib
rati
onp
erio
d(J
an19
83to
May
2010
).O
ut-
of-s
am
ple
fore
cast
sare
ob
tain
for
per
iod
from
Jan
1992
toM
ay20
10.
Mod
els
ofty
peA
use
only
the
info
rmat
ion
onth
efi
rst
lag
ofca
nd
idate
pre
dic
tors
.T
yp
eB
use
sa
mod
else
lect
ion
app
roac
hb
ased
onin
-sam
ple
crit
eria
(ad
just
edR
2,AIC
,BIC
).MSPE
stat
isti
csin
bold
corr
esp
on
dto
a10%
sign
ifica
nce
level
,in
bol
dan
dit
alic
toa
5%le
vel.
32
Tab
le6:
Sta
tist
ical
pre
dic
tive
per
form
ance
test
s:re
sult
sof
the
in-s
ample
and
out-
of-s
ample
fore
cast
ing
test
sduri
ng
per
iods
ofnor
mal
and
bullis
hm
arke
ts.
Lag
stru
ctu
reIn
-sam
ple
perf
orm
an
ce
Ou
t-of-
sam
ple
perf
orm
an
ce
Fin
anci
als
Em−y 1
0d
iff(E
m−y 1
0)
RM
SE
Th
eil’
sU
RM
SE
Th
eil’
sU
MS
PE
MS
PE
stat.
vs
Ust
at.
vs
Fin
.Uncond.Model
Un
on
on
o39
5.17
1.00
327.
031.
00
TypeA
A1
firs
tla
gn
on
o39
4.64
0.99
938
3.32
1.17
-0.9
1A
2fi
rst
lag
firs
tla
gn
o39
4.12
1.00
388.
341.
19
-1.0
2-1
.33
A3
firs
tla
gn
ofi
rst
lag
392.
660.
9938
1.79
1.17
-0.8
90.8
9A
4n
ofi
rst
lag
no
395.
421.
0033
3.99
1.02
-1.8
43.29
A5
no
no
firs
tla
g39
5.84
1.00
327.
471.
00
-0.0
83.14
TypeB
B1
opti
m.
lags
no
no
388.
220.
9833
5.83
1.03
0.8
4B
2op
tim
.la
gs10
,11
no
382.
330.
9732
9.39
1.01
1.4
81.66
B3
opti
m.
lags
no
1038
1.88
0.97
325.
280.
99
1.82
2.10
B4
opti
m.
lags
1,2,
10,1
1n
o38
1.32
0.96
334.
441.
021.0
31.1
4B
5op
tim
.la
gsn
o1,
2,10
,11
381.
230.
9632
7.95
1.00
1.5
62.03
B6
no
10,1
1n
o39
4.05
1.00
324.
040.
99
1.4
62.77
B7
no
no
1039
4.05
1.00
320.
230.
982.22
2.98
Notes:
Nor
mal
and
bu
llis
hm
arke
tp
erio
ds
are
defi
ned
by
excl
ud
ing
the
top
3d
raw
dow
np
erio
ds
mea
sure
din
the
pri
ceev
olu
tion
of
the
S&
P50
0to
tal
retu
rnin
dex
from
the
over
all
sam
ple
per
iod
.It
ther
efor
eex
clu
des
Ju
lyan
dA
ug
1998,
the
per
iod
start
ing
from
Sep
t20
00to
Feb
2003
,an
dfr
omD
ec20
07to
Feb
2009
.M
od
els
ofty
peA
use
only
the
info
rmat
ion
onth
efi
rst
lag
of
can
did
ate
pre
dic
tors
.T
yp
eB
use
sa
mod
else
lect
ion
app
roac
hb
ased
onin
-sam
ple
crit
eria
(ad
just
edR
2,AIC
,BIC
).MSPE
stati
stic
sin
bold
corr
esp
ond
toa
10%
sign
ifica
nce
level
,in
bol
dan
dit
alic
toa
5%le
vel.
33
Tab
le7:
Sta
tist
ical
pre
dic
tive
per
form
ance
test
s:re
sult
sof
the
in-s
ample
and
out-
of-s
ample
fore
cast
ing
test
sduri
ng
per
iods
ofb
eari
shm
arke
ts.
Lag
stru
ctu
reIn
-sam
ple
perf
orm
an
ce
Ou
t-of-
sam
ple
perf
orm
an
ce
Fin
anci
als
Em−y 1
0d
iff(E
m−y 1
0)
RM
SE
Th
eil’
sU
RM
SE
Th
eil’
sU
MS
PE
MS
PE
stat.
vs
Ust
at.
vs
Fin
.Uncond.Model
Un
on
on
o68
4.14
1.00
693.
731.
00
TypeA
A1
firs
tla
gn
on
o60
7.39
0.89
705.
801.
021.1
2A
2fi
rst
lag
firs
tla
gn
o60
8.86
0.89
709.
711.
02
1.1
2-0
.75
A3
firs
tla
gn
ofi
rst
lag
608.
070.
8971
0.96
1.02
1.0
6-0
.80
A4
no
firs
tla
gn
o68
4.63
1.00
692.
931.
000.3
21.69
A5
no
no
firs
tla
g67
9.95
0.99
697.
161.
00
-1.2
71.65
TypeB
B1
opti
m.
lags
no
no
587.
870.
8662
0.24
0.89
2.26
B2
opti
m.
lags
10,1
1n
o58
3.47
0.85
618.
820.
892.46
1.0
1B
3op
tim
.la
gsn
o10
585.
540.
8662
0.66
0.89
2.39
0.5
5B
4op
tim
.la
gs1,
2,10
,11
no
584.
360.
8562
4.12
0.90
2.38
0.6
3B
5op
tim
.la
gsn
o1,
2,10
,11
584.
310.
8563
2.03
0.91
2.23
-0.0
1B
6n
o10
,11
no
680.
911.
0069
6.14
1.00
0.5
4-0
.12
B7
no
no
1068
2.22
1.00
696.
421.
00
0.3
2-0
.12
Notes:
Bea
rish
mar
ket
per
iod
sco
rres
pon
dto
the
top
3d
raw
dow
np
erio
ds
mea
sure
din
the
pri
ceev
olu
tion
of
the
S&
P500
tota
lre
turn
ind
ex.
Itin
clu
des
Ju
lyan
dA
ug
1998
(LT
CM
coll
apse
),th
ep
erio
dst
arti
ng
from
Sep
t20
00to
Feb
2003
(inte
rnet
bu
bb
le),
an
dfr
omD
ec20
07to
Feb
2009
(rec
ent
fin
anci
alcr
ash).
Mod
els
ofty
peA
use
only
the
info
rmat
ion
onth
efi
rst
lag
of
can
did
ate
pre
dic
tors
.T
yp
eB
use
sa
mod
else
lect
ion
app
roac
hb
ased
onin
-sam
ple
crit
eria
(ad
just
edR
2,AIC
,BIC
).MSPE
stati
stic
sin
bold
corr
esp
ond
toa
10%
sign
ifica
nce
level
,in
bol
dan
dit
alic
toa
5%le
vel.
34
Table 8: Economic predictive performance tests: result of the asset allocation application.
Strategy Passive B1 B2 B1 B2
threshold = 0 bps threshold = -30 bpsOverall
Cumul. Ret. 74,03% 137,96% 178,15% 213,74% 252,23%Mean 4,02% 7,49% 9,67% 11,61% 13,70%
Std 14,94% 14,83% 14,73% 14,61% 14,46%Skewness -0,93 -0,08 -0,12 -0,15 -0,18
Excess Kurt. 1,92 1,72 1,82 1,92 2,07Sharpe R 0,27 0,50 0,65 0,79 0,94
JK stat vs passive 2,68 4,25 6,34 7,87JK stat vs active 3,02 2,85
Turnover 0,00 3,26 3,58 2,17 2,39Normal/bullish
Cumul. Ret. 220,49% 136,21% 155,11% 195,34% 225,56%Mean 15,21% 9,39% 10,70% 13,47% 15,56%
Std 11,13% 11,65% 11,56% 11,31% 11,08%Skewness -0,10 -0,13 -0,18 -0,09 -0,05
Excess Kurt. -0,12 -0,14 -0,06 -0,15 -0,18Sharpe R 1,36 0,80 0,92 1,19 1,40
JK stat vs passive -4,75 -3,58 -1,73 0,35JK stat vs active 1,57 2,38
Turnover 0,00 3,10 3,38 1,79 2,07Bearish
Cumul. Ret. -146,46% 1,75% 23,04% 18,40% 26,67%Mean -37,40% 0,45% 5,88% 4,70% 6,81%
Std 20,42% 23,15% 23,09% 23,11% 23,07%Skewness -0,27 0,17 0,04 0,06 0,01
Excess Kurt. -0,04 0,29 0,28 0,28 0,29Sharpe R -1,80 0,02 0,25 0,20 0,29
JK stat vs passive 6,68* 7,60* 7,50* 7,77*JK stat vs active 3,39 1,82
Turnover 0,00 3,83 4,34 3,57 3,57
Notes: The overall period for this analysis starts from Jan 1992 to May 2010. Bearish market
periods correspond to the top 3 drawdown periods measured in the price evolution of the S&P
500 total return index. It includes July and Aug 1998 (LTCM collapse), the period starting from
Sept 2000 to Feb 2003 (internet bubble), and from Dec 2007 to Feb 2009 (recent financial crash).
Mean returns and standard deviations are in annual terms. Turnover is the number of portfolio
rebalancing per year. *due to negative Sharpe ratio for the passive strategy during these periods,
the statistic cannot be interpreted.
35
6.3 Figures
Figure 1: Sample of US treasury yields of maturity 1, 3, 5 and 10 years. Yields are generatedusing the Nelson-Siegel-Svensson model and factors from Gurkaynak et al. (2007). NBERrecessions are in grey.
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
1985 1990 1995 2000 2005 2010
y1y3y5
y10
36
Figure 2: Estimates of parameter k.NBER recessions are in grey.
0
0.2
0.4
0.6
0.8
1
1985 1990 1995 2000 2005 2010
k
Figure 3: Estimates of parameter λ.
0
0.01
0.02
0.03
0.04
0.05
1985 1990 1995 2000 2005 2010
lam
bda
Figure 4: Estimates of parameter γ.
0
0.2
0.4
0.6
0.8
1
1985 1990 1995 2000 2005 2010
gam
ma
Figure 5: Estimates of weights ατ ofthe market portfolio.
0
0.2
0.4
0.6
0.8
1
1985 1990 1995 2000 2005 2010
alpha1alpha3alpha5
alpha 10
Figure 6: Annualized estimates of the expected return on the market portfolio Em, the10-year interest rate and the premium (Em − y10). NBER recessions are in grey.
-0.1
-0.05
0
0.05
0.1
0.15
1985 1990 1995 2000 2005 2010
Emy10
(Em - y10)
37
Figure 7: Cumulative difference of squared errors of out-of-sample prediction between a modelwith optimal lags of financial variables (B1) and the historical mean predictions. Periods ofmarket downturns are indicated in grey.
-0.02
-0.01
0
0.01
0.02
0.03
0.04
1992 1994 1996 1998 2000 2002 2004 2006 2008 2010
Cum
ulat
ive
SS
E d
iffer
ence
Figure 8: Cumulative difference of squared errors of out-of-sample prediction for model B2.Periods of market downturns are indicated in grey.
-0.02
-0.01
0
0.01
0.02
0.03
0.04
0.05
1992 1994 1996 1998 2000 2002 2004 2006 2008 2010
versus Uversus B1
38
Figure 9: Cumulative difference of squared errors of out-of-sample prediction for model B3.Periods of market downturns are indicated in grey.
-0.02
-0.01
0
0.01
0.02
0.03
0.04
0.05
1992 1994 1996 1998 2000 2002 2004 2006 2008 2010
versus Uversus B1
Figure 10: Cumulative difference of squared errors of out-of-sample prediction for model(B6). Periods of market downturns are indicated in grey.
-0.02
-0.01
0
0.01
0.02
1992 1994 1996 1998 2000 2002 2004 2006 2008 2010
versus Uversus B1
39
Figure 11: Cumulative returns of asset allocation strategies based on model out-of-sample forecasts.
The self-financing portfolio is rebalanced when models predict significant negative returns according
to a threshold of 30bps. Periods of market downturns are indicated in grey.
-0.5
0
0.5
1
1.5
2
2.5
3
1992 1994 1996 1998 2000 2002 2004 2006 2008 2010
PassiveB1B2
40