Macroeconomic Risk and Asset Pricing: Estimating the APT with Observable Factors
Abstract
This paper develops and applies a new maximum likelihood method for estimating the Arbitrage Pricing Theory (APT) model with observable risk factors. The approach involves simultaneous estimation of the factor loadings and risk premiums and can be applied to return panel with more securities than time series observations per security. Observable economic factors are found to account for 25 to 40 percent of the covariation in U.S. equity returns, and the APT pricing restrictions cannot be rejected for most sample periods. A significant "firm size anomaly" is measured, but it may be partly due to sample selection bias.
Board of Governors of the Federal Reserve System International Finance Discussion Papers Number 448
August 1993
MACROECONOMIC RISK AND ASSET PRICING: ESTIMATING THE APT WITH OBSERVABLE FACTORS
John Ammer
NOTE: International Finance Discussion Papers are preliminary materials circulated to stimulate discussion and critical comment. References in publications to International Finance Discussion Papers (other than an acknowledgment that the writer has had access to unpublished material) should be cleared with the author or authors.
ABSTRACT
This paper develops and applies a new maximum likelihood method for estimating the Arbitrage Pricing Theory (APT) model with observable risk factors. The approach involves simultaneous estimation of the factor loadings and risk premiums and can be appled to return panels with more securities than time series observations per security. Observable economic factors are found to account for 25 to 40 percent of the covariation in U.S. equity returns, and the APT pricing restrictions cannot be rejected for most sample periods. A signiticant "firm size anomaly" is measured, but it may be partly due to
sample selection bias.
MACROECONOMIC RISK AND ASSET PRICING: ESTIMATING THE APT WITH OBSERVABLE FACTORS
John Ammer?
1. Introduction
With models like CAPM and the APT, the finance profession has macle substantial progress in determining how the means of asset returns should be related, taking their variances and covariances as given. We have been somewhat less successful at explaining the sources of risk at the root of those variances and covariances. One strand of the literature has attempted to relate asset return innovations to news about future
variables.
The approach taken in this paper has its earliest antececlents in Chen, Roll, and Ross (1986). These authors treat news about the economy as observable risk in the context
of a factor model. Burmeister and McElroy (1988) go further in
0 The author is a staff economist in the International Finance
Division of the Board of Governors of the Federal Reserve System. Opinions expressed herein do not necessarily concur with those of the Federal Reserve Board or any other employees of the Federal Reserve System. I would like to thank Jianping Mei ancl workshop participants at the Federal Reserve Board and Princetion University for helpful conversations, and Jianping Mei, Tina Sun, and Chris Turner for assistance in obtaining data. However, I made all of the errors.
1 See Fama (1990), Campbell (1990), Campbell and Ammer (1991),
and Campbell and Mei (1991).
this direction, devising a means for estimating the Arbitrage Pricing Theory (APT) model with observable risk factors. This paper makes further technical progress in a new estimation method for the APT with observable factors which can handle a large enough amount of data to do justice to Ross! (1975) concept of no asymptotic arbitrage opportunities. The next section of the paper briefly reviews the APT, and the third section presents a maximum likelihood estimation method for the model. The next section discusses construction of the factor space and preliminary results of an application to U.S. equity return data. The fifth section develops improvements in measuring the observable factors, by incorporating revisions in expectations of future variables. The following section presents estimates and the results of some hypothesis tasts, and the subsequent one undertakes a brief investigation of the
firm size anomaly. The eighth section concludes the paper.
2. The APT Model
Assume that excess returns (over the risk-free rate) on
assets are generated by a linear factor model:
- of. : 1 Ll 1,) >j,t 1,t (1) for i=1, n and t=1, T
where E(f,) = 0, E(w; ) = 0, E(f5w;) = 0, and E(wswi) = 0.
The absence of asymptotic arbitrage opportunities (Ross 1976)
requires that for some vector di: » 2 Aa 2 , 17) J (2)
where the A are factor prices (risk premiums). With this
restriction, (1) can be rewritten: K : = b. .| A. + £. + W. 3 7i,t 7 2) i3| j 7 *4,t | i,t (3) or in matrix form:
Z = tA'B + FB +W (4)
where F is a matrix of (zero mean) random risk factors, B is a matrix of factor loadings, * A is a vector of factor prices, t
is a vector of ones, and the residuals We are independently and
identically distributed with zero mean and diagonal covariance
matrix Q.
2 More general specifications of the APT allow the factor
loadings to vary over time, for the factors and residuals to be heteroscedastic, and for the residuals to have non-zero covariances. However, the more restrictive version of the model we use here is common in the APT literature.
3. Estimation with Observable Factors
If one is to evaluate the importance of particular risk factors in the APT model, it is essential that the estimation method employed have three properties. First, it should be able to accommodate observable factors as inputs. In addition, one would like to be able to obtain consistent estimates and standarcl errors for the factor prices. A third property is also important if any asymptotic hypothesis testing will be done: t:she method should be capable of handling a large amount of data; in particular it should not require there to be more return observations per security than there are securities in
the model.
All of the estimation methods in the published literature on the APT fail to simultaneously satisfy all three of the criteria listed above. The techniques of Ross and Roll (1980) and Mei (1990), treat the factors as unobserved and cannot extract them. The methods presented in Lehmann and Modest (1988), Connor and Korajczyk (1988), and Mei (1991) infer the risk factors (F) from the covariance structure of returns. The factor estimates are returns on particular portfolios (with the means subtracted), and the means of these returns are consistent estimates of the risk premiums (A). Unfortunately,
with these methods, an additional step would be required to
relate an observable risk factor, such as inflation risk, to the extracted factor space. Without such further analysis, there is little that one would be able to say about the nature
of the risk that is priced.
Methods which use observable factors directly are potentially more appealing. Chen, Roll, and Ross (1986) apply the two step "cross-sectional regression" procedure of Fama and MacBeth (1973) to a panel of twenty size-sorted portfolios.° The first step is to obtain estimates of the factor loadings (B) by applying ordinary least squares to (1) with an unrestricted intercept (H;) for each security. Next, for each time period, the cross-section of security excess returns is regressed on the estimated factor loadings, to obtain estimates of the factor prices (A). Unfortunately, this technique suffers from an errors-in-variables problem in the second stage regression, which in general causes the precision of the estimates of the risk premiums (A) to be overstated. * In addition, there is no means for imposing the model rest:rictions
when estimating the factor loadings with this method, so that
it cannot truly be deemed a procedure for estimating the APT.
3 It is not clear why Chen, Roll, and Ross use so few assets,
since their methodology is not constrained in this’ dimension. Statistical power is lost by bundling assets into portfolios instead of allowing them to enter the estimation individually.
4 See Shanken (1992).
The APT estimation methods of Burmeister and McElroy (1988) and King, Sentana, and Wadhwani (1990) can handle both observed and unobserved factors, but both techniques require that there to be more return observations per security than there are securities in the model. Since the time series dimension of applications involving observable factors tends to be severely limited by the availability of macroeconomic data,
this shortcoming can be quite constraining.
The estimation method we use is the first to satisfy all three of our criteria above. Note that if all risk factors are observed, and a parameterization is chosen for the distribution of the residuals (W), equation (4) can be estimated directly by numerical methods, choosing the values of B and A which maximize the likelihood function.? we take this approach, allowing observable excess returns on well diversified portfolios to proxy for the unobservable dimensions of the
factor space, ° and assuming that the residuals are drawn from a
5 One negative feature of both our method and that of
Burmeister and McElroy (1988), is that it requires restrictions on the covariance matrix of the residuals. The Chen, Roll, and Ross (1986) paper is not subject to this criticism.
© Burmeister and McElroy (1988) also use returns as proxies for
latent factors. It is important to account for any unobservable risk factors that might be present in returns, because it will be assumed that the residuals will be uncorrelated across assets.
multivariate normal distribution.’ If the returns on these
portfolios have no idiosyncratic risk, ® they can be wrii:ten:
Za = [« Ag! + Fo| Boop + [' A! + F,| Buip (5)
where ut is a T-length vector of ones, the subscripts of F distinguish observed and unobserved factors, and Z_ and Fu are
assumed to have the same dimensions. If By p is nonsingular, ,
the observable factors and diversified portfolio excess returns
will jointly span the underlying factor space:
-1
' ' oy ' Fy + Agt _ I 0 Po Agt (6) Fo' + Ac! B_! B! zZ! u u o,p u,p p
In order to insure that the first matrix on the right side of
(6) is invertible, one should choose portfolios for Z_ with
7 This does not mean that the excess returns are themselves
multivariate normal, as not distributional assumption is made about the risk factors.
8 as discussed by Burmeister and McElroy (1988), non-zero
residuals in the portfolio returns proxying for the latent factors can bias the estimates of the risk premiums to the extent that the sample mean of those residuals differs from zero. In one of their applications, they attempt to avoid this problem by substituting projections of these returns’ onto instruments which are contemporaneous returns on assets’ that are neither in the portfolios or in the data panel on the right side of (4). Wanting as many securities as possible to be included in Z, we chose not to take their approach. As long as residual risk in our portfolio returns is small compared to the
factor risk, the effect on our estimates of A should be negligible.
some distinguishing features; if they have identical factor
loading:3, 25 will not be able to span a multidimensional latent
factor space.
Without loss of generality, we will assume that the unobserved factors are orthogonal to the observed factor space,” that they are mutually orthogonal, and that they have
unit variances. Under those assumptions, equation (5) implies
that _ -1 Boop = (Var(F.)) Cov(F., 24) (7) and ' = - Buip Buip Var (Zz) Cov (2, Fy) Bop (8) and = 1(B 'B Pup Chol (By ‘Bu, p) (9)
where Chol(-) denotes a Cholesky decomposition of a symmetric
matrix into an upper triangular matrix (and its transpose).
As, in some sense, they must be to truly be "unobserved".
Maximum likelihood estimation of (4) is facilitated by the
following shortcut:
Max £(A, B, F, Z) = Max [Max £(B, F, Z | A)] (10) A,B A B
Conditional on A, maximum likelihood estimates of B can be computed by ordinary least squares. Thus only Ky (the number of observable factors) of the Kn+K model parameters need to be involved directly in the numerical maximization of the likelihood function. For a given Aor F+A is computed firom (6). Then the OLS residuals from (3) can be used to compute the likelihood function. Asymptotic standard errors for the AG
estimates?° can be computed from the second derivatives: of
M(A | F, Z) = Max £(B, F, Z | A) (11) B
taken with respect to A.
10 The procedure does not provide standard errors for B, but
most of the hypotheses one would want to test involve only A.
10
4. Simple VAR Residuals as Factors
If financial markets are informationally efficient, asset prices should react to news about relevant economic variables. Accordingly, for the results reported in Tables 2-6, the
observable factors (Fo) are the residuals from a 5-lag vector
autorecression estimated from 1952 to 1990, +1 scaled to unit variance: 5 X = a A, X50 + Foot (12)
Table 1 lists the macroeconomic variables (X) in the VAR
specification.
The returns panel for a given sample period consists of all NYSE and AMEX firms for which there was a complete set of monthly returns on the 1990 CRSP tapes. The sample periods, which were chosen to correspond to Connor and Korajczyk (1988) and Mei. (1991), were 1979-1983, 1984-1988, 1964-1968, 1969-1973, and 1974-1978. An additional 1979-1983 sample was drawn for firms which were listed at the beginning of the
period and had at least 30 monthly return observations. ?? Note
11 the Akaike Information Criterion was applied to choose the lag length.
Allowing missing values in the returns panel substantially
11
that it is necessary to have at least K return observations to
identify the factor loadings for a given asset.
13
The portfolio returns used to identify the latent factors
were the first ten principal components of the individual excess returns panels. 14 These principal components are excess returns on portfolios formed from the securities in the panel. Similar results were obtained when capitalization-based New
York Stock Exchange (NYSE) decile portfolios were used instead.
Estimates of the model!> for the five sample periods appear in Tables 2-6. The second column of each table contains the estimated factor prices and standard errors from the negative inverse of the estimated Hessian matrix. The third column reports the average effect on the mean of an asset return from
exposure to each risk factor, which is simply the product of
increases the computation time for each evaluation of the likelihood function because the moment matrix of the factors is no longer the same for each return in the data panel.
13 Excess returns are over the one-month treasury bill return from Ibbotson (1991).
14 This is the Connor and Korajczyk factor extraction method.
The portfolio returns are the eigenvectors associated with the largest eigenvalues of 22Z'.
15 We used the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm
provided in the Gauss 2.01 MAXLIK module, with muamerical derivatives. Although analytical derivatives of the likelihood function are tractable, they are computationally very complicated, and some initial experimentation suggested that their use would actually increase the computation time required to achieve convergence.
12
the factcr price (plus the sample mean realization of the.
factor) and the mean factor loading. By choosing an order of orthogonalization, it is possible to decompose the R? of each return into contributions attributable to each of the factors;
these are reported in the rightmost column of the tables.
To interpret the estimated elements of A associated with the observable macroeconomic risk factors, it is helpful to borrow scme rough intuition from intertemporal asset pricing. Generally, assets that perform well when the endowment process (or econcmy) is doing poorly will have some hedging value, which will compensate for a lower mean return. Accordingly, assets with returns that covary positively with good news will be poor hedges, and should pay a premium return to compensate. Thus one would expect to estimate positive risk premiums for
"good news" risk factors and negative prices for "bad news"
factors.
A negative price was estimated for the PROD factor in all five sample periods, which was statistically significant in all but one case, implying that higher industrial production represents bad news for the economy, and is a contingency against which it is valuable to be able to hedge. This counter-intuitive result is the opposite of what was found by
Chen, Roll, and Ross (1986) over a similar sample period.
13
Perhaps more disturiing, in the 1984-1988 sample, the average factor loading for PROD was negative, implying that good news
about industrial production was bad news for the typical U.S.
equity security in the sample.
14
5. Constructing Forward-Looking Factors
There are two obvious problems with using VAR residuals to represent relevant economic factors. First, for the pricing of long-term assets, current innovations in macroeconomic variables may not matter as much as news about their future values. Secondly, if there is information other than lags of these variables which helps to forecast them, some portion of the estimated residuals from the VAR system, which excludes this extra information, reflects old news which should have
already been incorporated into asset prices.
In the results reported in Tables 8-18, these issues are
addressed by measuring the observable factors as
ot = Ge - Eee 37 Lf Xt (13)
ye (xz), (14)
where Zi is the excess return on the NYSE value-weighted market portfolio. Thus measurement of the factors will reflect
information about future realizations of X which have been
15
incorporated into the general level of U.S. equity prices. ?® By choosing to aggregate news about the economic variables for a period zero through twelve months ahead, we have arbitrarily limited (to a one-year horizon) the extent to which investors can be forward-looking. +’ It would be easy to modify the assumptions, by either changing the horizon or using a
discounted sum of forecast revisions.
Table 7 presents correlations of the excess return on the NYSE equal-weighted market portfolio with both the "residuals" factors Fo and the (forward-looking) "news" factors Fo These correlations are generally stronger for the "news" factors, which is a preliminary vindication of the forward-looking factor measurement method. This is in part because of the ability of ZVWM to help predict next month's macroeconomic variables (in the vector autoregression). Apparently investors have a lot of information about very short-term economic
prospects.
16 We implicitly assume that the variables in Y are observed
upon realization. This is not strictly true for data on aggregate sales, production, and consumer prices. However, Huberman and Schwert (1985) found that investors in indexed Israeli government bonds were very good at forecasting the consumer price index data releases to which the bonds were indexed.
17 A horizon of at least one year seemed appropriate because
Fama (1990) has found that market portfolio returns predict production growth up to 12 months ahead.
16
6. Results and Hypothesis Tests
Tables 8-12 contain estimates of (4) for all five sample periods using the "news" factors. Significantly positive risk premiums were estimated for the PROD* factor in the 1979-1983 sample, and for the SALE* factor!® in three of the sample periods. These results suggest that investors demand a higher
mean return from assets with pro-cyclical returns, because they
have poor hedging value.
For three of the samples, a negative risk premium was estimated for the oil price factor. Under the logic of intertemporal asset pricing, this would be consistent with high oil prices; being bad news for the economy of the United States, a net importer. Using similar methodology, Ammer (1992, chapter 3) measured a positive oil factor price for equities
traded in the UK, a net oil exporter.
For four of the periods, a negative risk premium was
estimated for inflation news. +? This result suggests that
18 Our postive risk premium estimates for the SALE* factor in
the 1974-1978 and 1979-1983 periods contrast the negative factor price estimated for a final sales factor by Burmeister
and McElroy (1988) using a sample of 70 securities from 1972 to 1982.
19 Chen, Roll, and Ross (1986) also estimated a negative inflation factor price for the period 1958-1984.
17
securities which are good hedges against inflation are
perceived to have extra value.
Negative risk premiums were estimated for both of tae yield spread factors in most of the periods. For the corporate bond quality spread, this is consistent with default risk increasing during periods of bad economic news. The negative risk premium estimated for the maturity yield curve factor
suggests that relatively high long term interest rates are bad
for the economy.
The contribution of the observable factors to the mean R’* ranges from 25 to 40 percent in these samples, compared to 20 to 30 percent when the "residual" factors were used. Nevertheless, unobservables are still driving the majority of
the covariation in asset returns.
Likelihood ratio (LR) tests of the APT pricing restrictions can be performed by comparing the likelihood values reported in the tables to those obtained from unrestricted ordinary least squares estimation of equation (1).
We fail to reject at the five percent level in four out of five
cases.
In addition, variation in factor loadings typically
18
accounts for between 35 and 40 percent of the cross-sectional variation in returns in a given time period. Variations in the sensitivity of returns to the six observable factors usually accounts for about 10 percent of this cross-sectional
variation.
Table 13 presents estimates of Ay which have been restricted to be the same across all five samples. 7° A likelihood ratio test leads to strong rejection of the
restriction, suggesting that factor prices may not be stable
over time.
All of the results discussed so far are for panels of returns with no missing values. In other words, the samples have excluded companies for which listing on the NYSE or AMEX was discontinued sometime during the period. If such firms are fundamentally different from the survivors, the results may be biased. Table 14 presents estimates for 1979-1983 for all firms with at least thirty (not necessarily consecutive) return observations. The estimated factor prices are very close to
the results reported in Table 8.
20 Note that it would not be appropriate to Similarly restrict Aue because the portfolios from which the unobservable factors
are constructed vary across sample periods.
19
Tables 15 and 16 contain results for 1979-1983 in which one of the 16 factors has been dropped from the specification reported in Table 8. [In Table 15, the tenth latent factor is omitted, which has little effect on the estimated risk premiums for the observable factors. Nevertheless, a likelihood ratio test leads to strong rejection of the null hypothesis that the sixteenth factor is redundant. Table 16 reports estimates for a 15-dimensional factor space which excludes ROIL*. Because this model is nested by the 16-factor model, it appears at first blush that an LR test statistics would have an asymptotic v2 distribution when the restricted model is the true mcdel. This is not the case. When all of the (n) loadings for a particular factor are restricted to be zero, the price cf that factor becomes unidentified. 7+ However, the results of Monte Carlo simulations (see Appendix A) suggest that when n is large, the 95% quantile of the statistic is fairly close to that of of the xv? (n+1) distribution. With a test statistic of about 2744, one can confidently reject the null hypothesis of exclusion of the ROIL* factor. Yet an application of the Akaike Information Criterion, which would be more oriented to parsimonious model choice than LR tests on large numbers of
restrictions, would lead to dropping the oil factor.
21 Note that this is a feature of the APT model in general, not
of this estimation method. Garcia and Perron (1990) document a similar problem for testing for the number of discrete states in a regime switching model.
20
7. The Firm Size Anomaly
This estimation framework can also be used to test the APT against specific alternatives which nest it. Some of the interesting alternatives are anomalies against which the older CAPM moclel was rejected, such as the "small firm effect", under which the equities of firms with lower ex ante market capitalizations have higher mean returns than larger firms, even after adjusting for market risk. 2 One could test for a
security-specific effect by augmenting the APT equation (4) to Z = cAS' + (ct A' + F)B + W (15)
where S is a vector of security characteristics and A is a
scalar t:o be estimated.
Under this alternative model, the excess returns on well
diversified portfolios would be
= ' ' ' Z, = LASS + [e4, + Fo|Bo, p + [es + Fa} Bu,p (16) where Sy = G'S and G is the matrix of portfolio weights.
22 This was first discovered by Banz (1981).
21
If G is known, estimation can proceed as above. However, when the portfolios are principal components of the return panel (Z), extracting the portfolio weights can be computationally expensive.?? For the application presented here, we chose the alternative of estimating So (along with A
and A.) by allowing it to enter as parameters to the numerical
likelihood maximization.
Table 17 presents estimates of (15) in which S is the difference between the firm's log capitalization at the beginning of the sample (January 1, 1979) and the mean log capitalization at that time for all firms in the sample. A significant size effect is measured here, but it could be due to sample selection bias. Smaller firms are much more likely to drop out of the sample (from ceasing to be listed on the exchange). If, as seems reasonable, the casualties tend to be securities that have "performed" poorly, the ex post mean
returns for survivors will overstate their ex ante means.
The sample selection bias problem is reduced in the results reported in Table 18. Assets are included in the sample if they made it at least half of the way through. The
estimated size effect coefficient is only slightly smaller, and
23 In particular, it involves computing eigenvectors of ann by n matrix.
22
translates to two percent being either added to or subtracted
from the annual return on a typical security in the sample.
This result contrasts what was found by Chan, Chen, and Hsieh (1985), who applied the Fama and MacBeth (1973) cross-sectional regression methodology to the same data set used by Chen, Roll, and Ross (1986). In particular, they used the excess returns on twenty size-sorted portfolios as Z in (1). They found that high correlation between their portfolio of the smallest firms and a factor similar to RISK, for which they had estimated a large negative risk premium, explained the high mean return on this portfolio. However, because of the statistical power which is sacrificed by bundling securities into portfolios, it is hard to know whether the assets in this portfolio which cause its return to be correlated with the default: risk spread are the same ones which cause the mean return to be high. For example, some of the firms in the sample may have equity returns which are negatively correlated with RISK simply because their debt securities are constituents
of the measured BAA bond yield, while others have a high mean
return for unrelated reasons.
23
8. Conclusions
This paper develops a new maximum likelihood method for estimating the Arbitrage Pricing Theory (APT) model with observable risk factors. The use of observable factors in the APT enables greater economic interpretation of the systematic risk which is (or is not) priced. The technique produces consistent standard errors for the factor prices, it allows one to impose (and test) the APT model pricing restrictions, and can be applied to panels of return data with more securities
than time series observations per security.
The ability to handle large cross-sections appear to have allowed us to estimate the risk premiums more precisely. We estimate factor prices significantly different from zers (using a test size of five percent) more often than do Burmeister and McElroy (1988). In addition, note that the standard errors reported by Chen, Roll, and Ross (1986) overstate the precision of their estimates because they do not correct for the errors-in-variables problem that arises in their multi-stage estimation procedure. If the APT model is true, then our method, in which one can impose the APT restrictions should
produce more precise estimates, as well as consistent standard
errors.
24
Our technique is applied to several large panels of U.S. equity returns. Observable economic factors are found to account for 25 to 40 percent of the common variation in excess returns over the risk-free rate. A number of factor prices are found to be significantly different from zero, but estimates do not appear to be stable over different sample periods. The APT
pricing restrictions cannot be rejected for most of the sample
periods.
A significant "firm size anomaly" is measured, which
appears not to be entirely due to sample selection bias.
25
Appendix A: Monte Carlo Distribution of LR Statistic
For each simulation, the APT was estimated with zero and one factors on 60 observations on 1797 returns, where the true model: was white noise (zero factors). Likelihood ratio
statistics were computed for 1000 simulations.
95% quantile of empirical distribution: 971.123 95% quantile of x? (1798) distribution: 948.738 x? quantile of empirical critical value: 0.009 empirical quantile of x? critical value: 0.186
26
References
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27
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28
Table 1
Construction of Factor Space for APT Models
Observable Factors are based on the residuals from a VAR(5) :
eee PROD growth in industrial production (seasonally adjusted)
ROIL log relative (to CPI) wholesale price of oil (SA)
GCPI Consumer Price Index (all items) inflation (SA)
SALE growth in total real final retail sales (SA)
RISK yield spread between BAA bonds and AAA corporate bonds
TERM yield spread between 10-year and 3-month treasury securities
For the results reported in tables 8-18, the following variable
is added to the VAR system to improve forecasting power:
ZVWM excess return (over the 1l-month treasury bill) on the New York Stock Exchange Value-Weighted Market Index
In addition, the factors used there are news about the average values of the VAR variables for the current and next 12 months
. , 22 Pot = (fe - Ee) a LE Xe;
instead of the VAR residuals used for tables 2-6
Po t = (Ee - Ee) % -
The Latent Factor space is comprised by the components of excess returns (over the 1-month treasury bill) on well-diversified portfolios which are orthogonal to the observable factor space.
29
Table 2
1797 returns
ln(£) = 137379.753 average R® = 0.551. name mean average of A annual variance factor A boost share i PROD -0.052 -0.003 0.025 (0.031) ROIL -0.212 -0.005 0.015 (0.024) GCPI -0.285 0.010 0.023 (0.038) SALE 0.026 0.007 0.022 (0.028) RISK 0.029 -0.001 0.018 (0.063) TERM 0.017 -0.002 0.014 (0.070) total: 0.116 with APT restrictions relaxed: In(£) = 138230.339 x? P-value for LR test: 0.911
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
Table 3
Estimates of 16 Factor APT Model, 1/84-12/88
1529 returns
in(£) = 124137.187 average R* = 0.576 nanie mean average of A annual variance factor A boost share eee PROD -0.096 0.016 0.032 (0.024) ROIL -0.208 0.010 0.019 (0.054) GcPI 0.054 -~0.001 0.012 (0.044) SALE -0.339 0.026 0.020 (0.049) RISK -0.038 -0.004 0.013 (0.037) TERM 0.051 0.001 0.012 (0.076) eee total: 0.106
a nen
with APT restrictions relaxed: in(£) = 124934.547
x2 P-value for LR test: 0.118 a eee Notes: 10 latent factors were derived from the first 10 principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance, The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
31
Table 4
Estimates of 16 Factor APT Model, 1/64-12/68
1529 returns
In(2) = 122654.691 average R? = 0.506 name mean average of n annual variance factor A boost share eee PROD -0.064 0.000 0.013 (0.032) ROIL 0.123 0.000 0.016 (0.006) GCPI 0.103 0.000 0.019 (0.028) SALE 0.434 -0.031 0.016 (0.052) RISK -0.079 0.051 0.026 (0.018) TERM -0.024 -0.002 0.014 (0.009) a total: 0.104
with APT vestricticns relaxed: Iin(#) = 123324.675 «" P-value fer LR test: 9.999 Motes: io caters factors were derived from the first 10 principal xcwponents of the excess return panel. Standard errors are in parentheses. Factors are caled to unit , . . 2 variance. The contributions to R are calculated by
orthogona «zing the observable factors in their order of appearance.
32
Table 5
Estimates of 16 Factor APT Model, 1/69-12/73
1800 returns
ln(2) = 141107.095 average R? = 0.608 name mean average of A” annual variance factor A boost share eee PROD -0.251 -0.045 0.037 (0.028) ROIL 0.251 0.001 0.016 (0.009) GCPI -0.046 -0.009 0.024 (0.037) SALE -0.235 -0.000 0.013 (0.032) RISK -0.081 0.003 0.028 (0.016) TERM -0.019 -0.035 0.015 (0.009)
total: 0.133
ee with APT restrictions relaxed: In(2) = 141975.141
x P-value for LR test: 0.788
LSS SSeS hoe pss Ss
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
Table 6
1808 returns
in(2) = 142455.091 average R? = 0.651 name mean average of A annual variance factor A boost share ee PROD -0.121 -0.005 0.017 (0.039) ROIL -0.066 0.010 0.028 (0.018) GCPI -0.378 0.049 0.043 (0.037) SALE 0.059 0.027 0.031 (0.038) RISK 0.311 -0.033 0.016 (0.029) TERM -0.201 0.050 0.013 (0.012) a total: 0.149 ie with APT restrictions relaxed: In(£) = 143473.602 x? P-value for LR test: 0.000
serene
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
34
Table 7
Correlation of Factors and Equal-Weighted NYSE, 1/64 - 2/88
factors which are contemporary residuals
PROD ROIL GCPI SALE RISK 1.00 0.05 0.06 0.29 -0.13 1..00 0.16 0.05 -0.02
1.00 -0.07 0.05
1.00 -0.18
1.00
TERM
-0.13
-0.06
-0.05
-0.00
ZEWM
PROD
ROIL
GCPI
SALE
RISK
TERM
ZEWM
factors which are news about mean ef variable 0-12 months ahead
OO eee OE “St
PROD* ROIL* GCPI* SALE* RISK* 1.00 -0.04 -0.19 0.76 -0.69 1.00 0.52 -0.21 0.26
1.00 -0.38 0.16
1.00 -0.44
1.00
35
TERM*
0.23
~0.54
-0.36
ZEWM
0.48
0.07
-0.18
PROD*
ROIL*
GCPI*
SALE*
RISK*
TERM*
ZEWM
Table 8 Estimates of 16 Factor APT Model, 1/79-12/83
1797 returns
In(£) = 137282.520 average R? = 0.551 name mean average of n annual variance factor A boost share ees PROD* 0.119 -0.022 0.041 (0.037) ROIL* ~0.216 -0.001 0.016 (0.030) GCPI* -0.278 0.002 0.025 (0.037) SALE* 0.204 0.036 0.023 (0.036) RISK* -0.118 0.006 0.020 (0.061) TERM* 0.032 0.024 0.019 (0.068) _ eee total: 0.146
TT eeeeeeseeesess—=* with APT restrictions relaxed: In(£) = 138129.939
v* P-value for LR test: 0.927
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
36
Table 9
1529 returns
in(£) = 124065.147 average R? = 0.576 name mean average of A annual variance factor A boost share PROD* -0.054 -0.028 0.070 (0.029) ROIL* -0.300 -0.014 0.016 (0.057) GCPI* -0.046 0.013 0.016 (0.047) SALE* -0.166 0.008 0.023 (0.043) RISK* -0.174 0.011 0.012 (0.037) TERM* 0.206 -0.027 0.018 (0.077) total: 0.156 with APT restrictions relaxed: ln(#) = 124860.991 v2 P-value for LR test: 0.129
Notes: 10 latent factors were derived from the first 10
princir’1 components of the excess return panel. Standard errors ure in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
37
Table 10
1529 returns
ln(2) = 122828.669 average R? = 0.509 name mean average of A annual variance factor A boost share PROD* 0.008 0.002 0.039 (0.023) ROIL* 0.124 -0.000 0.016 (0.009) GCPI* 0.168 -0.012 0.029 (0.028) SALE* 0.193 -0.016 0.016 (0.032) RISK* -0.022 0.097 0.041 (0.016) TERM* -0.067 0.024 0.023 (0.009) total: 0.164 with APT restrictions relaxed: In(£) = 123537.948 v2 P-value for LR test: 0.959
Notes: 10 latent factors were derived from the first 10
principal components cf the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
38
Table 11
Hstimates of 16 Factor APT Model, 1/69-12/73
1800 returns
In(£) = 141102.873 average R? = 0.609 name mean average of A annual variance factor A boost share PROD* -0.174 0.014 0.146 (0.029) ROIL* 0.175 0.004 0.016 (0.014) GCPI* -0.046 0.002 0.012 (0.035) SALE* -0.189 -0.037 0.014 (0.034) RISK* -0.016 -0.022 0.039 (0.017) TERM* -0.039 0.027 0.014 (0.010) -_—_———— eee total: 0.240
-_——— esses with APT restrictions relaxed: in(£) = 142003.209
x? P-value for LR test: 0.387
errr eee Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance,
39
Table 12
1808 returns
In(#2) = 142515.480 average R2 = 0.652 name mean average of A annual variance factor A boost share PROD* -0.020 -0.005 0.128 (0.034) ROIL* -0.086 0.000 0.029 (0.021) GCPI* -0.281 0.020 0.026 (0.037) SALE* 0.117 0.071 0.022 (0.031) RISK* 0.178 -0.043 0.035 (0.025) TERM* -0.205 -0.020 0.021 (0.011) total: 0.261 with APT restrictions relaxed: ln(£) = 143580.814 v2 P-value for LR test: 0.000
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
40
Table 13
Estimates of 16 Factor APT Model, 1/64-12/88 factor prices restricted to be the same for 5 sub-periods
In(2) = 667193.625
name of A factor A
PROD* -0.005
(0.015)
ROIL* 0.104
(0.007)
GCPI* 0.052
(0.019)
SALE* 0.064
(0.017)
RISK* -0.005
(0.011)
TERM* -0.068 (0.008)
with A restrictions relaxed: ln(2) = 667794.640
x? P-value for LR test: 0.000
Sass SSS ss Schepf
Notes: 10 latent factors were derived from the first 10
principal components of each excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance.
41
Table 14
Estimates of 16 Factor APT Model, 1/79-12/83
2123 returns
In(£) = 152587.326 average R? = 0.595 name mean average of A annual variance factor A boost share eee PROD* 0.120 -0.023 0.042 (0.035) ROIL* -0.229 -0.002 0.017 (0.031) GCPI* -0.305 0.003 0.028 (0.038) SALE* 0.215 0.042 0.026 (0.038) RISK* -0.122 _ 0.006 . 0.021 (0.059) TERM* 0.023 0.025 0.020 (0.072) total: 0.155 ©
—_—_—e'oooee
with APT restrictions relaxed: 1n(£) = 153720.179
v2 P-value for LR test: 0.012 —_—_-eOOQ error Notes: 10 latent factors were derived from the first 10
principal components of the excess’ return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance. Assets with missing returns were included if they had at least 30 observations in the 60 month sample period.
42
Table 15
Estimates of 15 Factor APT Model, 1/79-12/83
1797 returns
In(2) = 135324.253 average R? = 0.535 name mean average of A annual variance factor A boost share PRO)D* 0.118 -0.021 0.041 (0.038) ROI‘L* -0.213 -0.000 0.016 (0.030) GCPI* -0.270 0.002 0.025 (0.036) SALIE* 0.202 0.035 0.023 (0.037) RISK* -0.120 0.006 0.020 (0.063) TERM* 0.039 0.023 0.019 (0.069) eee total: 0.146
————————————
with APT restrictions relaxed: in(£) = 136142.601 x2 P-value for LR test: 0.993 y P-value for adding 16th factor: 0.000 — eee Notes: 2 latent factors were derived from the first 9 principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
43
Table 16
1797 returns
ln(2) = 135910.605 average R? = 0.539 name mean average of A annual variance factor A boost share — PROD* 0.102 -0.017 0.041 (0.036) GCPI* -0.317 -0.004 0.021 (0.038) SALE* 0.219 0.045 0.023 (0.037) RISK* -0.071 -0.002 0.014 (0.060) TERM* 0.015 0.035 0.031 (0.067) eee total: 0.131
rr rrr ree sneennecneneeere,
with APT restrictions relaxed: in(2) = 136745.636 x? P-value for LR test: 0.971 x? P-value for adding 16th factor: 0.000
eee Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
44
Table 17
Estimates of 16 Factor APT Model, 1/79-12/83, allowing for firm size effect on mean return
—_—_—_—_—_—<<—SS OE I
1797 returns
in(2) = 137322.520 average R? = 0.551 annualized (relative log) size effect: -0.014 (0.002) mean absolute value of size effect on mean: 0.021 effect on smallest firm: 0.064 effect on largest firm: -0.089 name mean average of A annual variance factor A boost share PROD* 0.153 0.002 0.041 (0.036) ROJ:L* ~0.232 -0.000 0.016 (0.029) GCPI* -0.385 0.002 0.025 (0.039) SALE* 0.296 -~0.002 0.023 (0.037) RISK* -0.107 -0.000 0.020 (0.059) TERM* 0.120 -0.001 0.020 (0.067) eee total: 0.145
_ ees
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance.
45
Table 18
Estimates of 16 Factor APT Model, 1/79-12/83, effect on mean return
OO Oe EO tO
2123 returns
ln(£) = 152644.653 average R* = 0.595 annualized (relative log) size effect: -0.013 (0.002) mean absolute value of size effect on mean: 0.020
effect on smallest firm: 0.063 effect on largest firm: -0.084
name mean average of ~ annual variance factor A boost share PROD* 0.135 0.001 0.042 (0.035) ROIL* -0.224 -0.000 0.017 (0.031) GCPI* -0.356 0.001 0.028 (0.038) SALE* 0.284 -0.001 0.026 (0.038) RISK* -0.080 0.000 0.021 (0.056) TERM* 0.094 -0.000 0.020 (0.072) a total: 0.155
Notes: 10 latent factors were derived from the first 10
principal components of the excess return panel. Standard errors are in parentheses. Factors are scaled to unit variance. The contributions to R? are calculated by
orthogonalizing the observable factors in their order of appearance. Assets with missing returns were included if they had at least 30 observations in the 60 month sample period.
46
IFDP NUMBER
448
447
446
445
444
443
442
441
440
439
438
437
436
Please address requests for co Division of International Finance, Reserve System, Washington, D.C.
International Finance Discussion Papers
TITLES
1993
Macroeconomic Risk and Asset Pricing: Rstimating the APT with Observable Factors
Near observational equivalence and unit root processes: formal concepts and =mplications
Market Share and Exchange Rate Pass-Through in World Automobile Trade
Industry Restructuring and Export Performance: Evidence on the Transition in Hungary
Exchange Rates and Foreign Direct Investment: A Note
Global versus Country-Specific Productivity Shocks and the Current Account
The GATT'’s Contribution to Economic F.ecovery in Post-War Western Europe
4. Utility Based Comparison of Some Models of Exchange Rate Volatility
Cointegration Tests in the Presence of Structural Breaks
1992
Life Expectancy of International Cartels: 4n Empirical Analysis
[Daily Bundesbank and Federal Reserve Intervention and the Conditional Variance Tale in DM/$-Returns
War and Peace: Recovering the Market's Probability Distribution of Crude Oil Futures Prices During the Gulf Crisis
Growth, Political Instability, and the Defense Burden
20551.
47
AUTHOR (s)
John Ammer
Jon Faust
Robert C. Feenstra Joseph E. Gagnon Michael M. Knetter Valerie J. Chang Catherine L. Mann
Guy V.G. Stevens
Reuven Glick Kenneth Rogoff
Douglas A. Irwin
Kenneth D. West Hali J. Edison Dongchul Cho
Julia Campos Neil R. Ericsson David F. Hendry
Jaime Marquez
Geert J. Almekinders Sylvester C.W. Eijffinger
William R. Melick Charles P. Thomas
Stephen Brock Blomberg
pies to International Finance Discussion Papers, Stop 24, Board of Governors of the Federal
IFDP NUMBER
435
434
433
432
431
430
426
424
423
422
421
International Finance Discussion Papers TITLES
1992
Foreign Exchange Policy, Monetary Policy, and Capital Market Liberalization in Korea
The Political Economy of the Won: U.S.-Korean Bilateral Negotiations on Exchange Rates
Import Demand and Supply with Relatively Few Theoretical or Empirical Puzzles
The Liquidity Premium in Average Interest Rates
The Power of Cointegration Tests
The Adequacy of the Data on U.S. International Financial Transactions: A Federal Reserve Perspective
Whom can we trust to run the Fed? Theoretical support for the founders views
Stochastic Behavior of the World Economy under Alternative Policy Regimes
Real Exchange Rates: Measurement and implications for Predicting U.S. External imbalances
Central Banks’ Use in East Asia of Money Market Instruments in the Conduct of Monetary Policy
Purchasing Power Parity and Uncovered Interest Rate Parity: The United States 1974 - 1990
Fiscal Implications of the Transition from Planned to Market Economy
Does World Investment Demand Determine U.S. Exports?
The Autonomy of Trade Elasticities: Choice and Consequences
German Unification and the European Monetary System: A Quantitative Analysis
48
AUTHOR(s)
Deborah J. Lindner
Deborah J. Lindner
Andrew M. Warner
Wilbur John Coleman II Christian Gilles Pamela Labadie Jeroen J.M. Kremers Neil R. Ericsson Juan J. Dolado
Lois E. Stekler Edwin M. Truman Jon Faust
Joseph E. Gagnon Ralph W. Tryon
Jaime Marquez
Robert F. Emery
Hali J. Edison William R. Melick
R. Sean Craig Catherine L. Mann
Andrew M. Warner
Jaime Marquez
Gwyn Adams Lewis Alexander Joseph Gagnon
Cite this document
John Ammer (1993). Macroeconomic Risk and Asset Pricing: Estimating the APT with Observable Factors (IFDP 1993-448). Board of Governors of the Federal Reserve System, International Finance Discussion Papers. https://whenthefedspeaks.com/doc/ifdp_1993-448
@techreport{wtfs_ifdp_1993_448,
author = {John Ammer},
title = {Macroeconomic Risk and Asset Pricing: Estimating the APT with Observable Factors},
type = {International Finance Discussion Papers},
number = {1993-448},
institution = {Board of Governors of the Federal Reserve System},
year = {1993},
url = {https://whenthefedspeaks.com/doc/ifdp_1993-448},
abstract = {This paper develops and applies a new maximum likelihood method for estimating the Arbitrage Pricing Theory (APT) model with observable risk factors. The approach involves simultaneous estimation of the factor loadings and risk premiums and can be applied to return panel with more securities than time series observations per security. Observable economic factors are found to account for 25 to 40 percent of the covariation in U.S. equity returns, and the APT pricing restrictions cannot be rejected for most sample periods. A significant "firm size anomaly" is measured, but it may be partly due to sample selection bias.},
}