Unconditional Tests of Linear Asset Pricing Models with Time‐Varying Betas

In conditional affine factor models, estimated risk prices should satisfy certain unconditional constraints. Specifically, a cross‐sectional estimate of the unconditional slope associated with a risk factor should equal the average price of risk of the factor. The estimated slope associated with the product of a risk factor and an instrument should be equal to the covariance of the factor risk premium with the instrument. We show that the constraints only apply to the conditional models with time‐varying betas. We identify an unconditional constraint on unconditional betas for time‐varying beta models and incorporate it into model tests. We show that imposing this unconditional constraint changes estimates of unconditional betas and risk prices significantly.     

A General Affine Earnings Valuation Model

We introduce a methodology, with two applications, that incorporates stochastic interest rates, heteroskedasticity and risk aversion into the residual income model. In the first application, goodwill is an affine (constant plus linear term) function where the constant and linear coefficients are time-varying. Homoskedastic risk gives rise to a constant risk premium, while heteroskedastic risk gives rise to linear state-dependent risk premiums. In the second application, we present a class of models where a non-linear function for the price-to-book ratio can be derived. We show how interest rates, risk, profitability and growth affect the price-to-book ratio.     

Modeling Foreign Exchange Risk Premium in Armenia

This paper applies stochastic discount factor methodology to modeling the foreign exchange risk premium in Armenia. We use weekly data on foreign and domestic currency deposits, which coexist in the Armenian banking system. This coexistence implies elimination of the cross-country risks and transaction costs, leaving the pure foreign exchange risk. It is shown that there exists a systematic time-varying risk premium that increases with maturity. Using two-currency affine term structure and generalized autoregressive conditional heteroskedasticity (GARCH)-in-mean models, we find that the central bank's foreign exchange market interventions and ratio-of-deposit volumes significantly affect public expectations about foreign exchange fluctuations. We also find that the foreign exchange risk premium accounts for the largest part of the interest differential. When accounting for economic and institutional differences, our results can be extended to other countries.     

THE TIME‐VARYING EQUITY PREMIUM AND THE S&P 500 IN THE TWENTIETH CENTURY

I present a new hindcast stock market index for the United States over the twentieth century. This is constructed by calibrating a rational asset pricing model that allows for a time‐varying equity premium driven by heteroskedasticity in consumption growth. By incorporating this variation in risk, the mean square error of the generated index series, when compared to the observed levels of the S&P 500, is significantly reduced. The model also explains the broad magnitudes and timings of the major bull and bear markets of the twentieth century, particularly before 1973, and the excess volatility puzzle is largely resolved.     

Local risk factors in emerging markets: Are they separately priced?

We provide new evidence on the pricing of local risk factors in emerging stock markets. We investigate whether there is a significant local currency premium together with a domestic market risk premium in equity returns within a partial integration asset pricing model. Given previous evidence on currency risk, we conduct empirical tests in a conditional setting with time-varying prices of risk. Our main results support the hypothesis of a significant exchange risk premium related to the local currency risk. Exchange rate and domestic market risks are priced separately for our sample of seven emerging markets. The empirical evidence also suggests that although statistically significant, local currency risk is on average smaller than domestic market risk but it increases substantially during crises periods, when it can be almost as large as market risk. Disentangling these two factors is thus important in tests of international asset pricing for emerging markets.     

Market timing for the individual investor: Using the predictability of long-horizon stock returns to enhance portfolio performance

Recent research indicates that dividend yield and earnings-price ratio can partially predict long-horizon stock returns. We examine whether individual investors can successfully construct timing portfolios based on either of these variables or a measure of the expected market risk premium. The out-of-sample tests in this study require that investors rely only on information that was available at the time of the market-timing decision. Timing portfolios based on the market risk premium show the strongest ability to time the market. We present an economic rationale for the results that is consistent with efficient markets.     

Is the ex‐ante equity risk premium always positive? Evidence from a new conditional expectations model

We model the conditional risk premium by combining principal component analysis and a statistical learning technique, known as boosted regression trees. The method is validated through various out‐of‐sample tests. We apply the estimates to test the positivity restriction on the risk premium and find evidence that the risk premium is negative in periods of low corporate and government bond returns, high inflation and downward‐sloping term structure. These periods are linked with changes in business cycles; the states when theories predict the existence of negative risk premium. Based on the evidence, we reject the conditional capital asset pricing model and raise a question over the practice of imposing the positive risk premium constraint in predictive models.     

International asset pricing under segmentation and PPP deviations

We analyze the impact of both purchasing power parity (PPP) deviations and market segmentation on asset pricing and investor's portfolio holdings. The freely traded securities command a world market risk premium and an inflation risk premium. The securities that can be held by only a subset of investors command two additional premiums: a conditional market risk premium and a segflation risk premium. Our model is empirically supported with important implications for tests of international asset pricing.     

The evolution of pay premiums for managerial attributes

This paper proposes and estimates an interactive fixed effects model of executive compensation, which allows for time-variant pay premiums for unobserved manager attributes. We find that two managerial traits can explain executive compensation over time: talent and conservatism. The market premium for talent is higher in bull markets, as the higher marginal productivity of human capital during these periods increases the demand and thus the price for talents. Such pay premium is concentrated among top talented managers, who earn a premium about five times that of median talented managers. The pay premium for conservatism is linked to the equity market risk premium, with conservatism being discounted (compensated) during the low (high) risk premium periods. We show that risk-taking managers are rewarded during the early period of our sample. However, after the periods characterized by higher risk premium, such as the financial crisis, conservatism becomes a more desirable trait.     

Assessing the Efficiency of an Insurance Provider—A Measurement Error Approach

The purpose of this paper is to compare the cost efficiency of private and public property insurance providers in Switzerland. The most commonly used measure for this kind of exercise is the claims-premium ratio. We argue that this measure may give strongly biased results. We develop a simple model to test whether the elasticity of premiums with respect to claims is less than unity. We address the fact that premium income is relatively stable across time, while claims are not, using estimation techniques that correct for measurement error. We develop tools to cope with heteroskedasticity in such measurement errors and apply the model to a data set on 19 firms in housing insurance markets in Switzerland. We show that the public insurance providers are about 20% more cost efficient than their private counterparts.JEL Classification No.: C21, D21, L84     

Age‐Dependent Increasing Risk Aversion and the Equity Premium Puzzle

We introduce a new preference structure—age‐dependent increasing risk aversion (IRA)—in a three‐period overlapping generations model with borrowing constraints, and examine the behavior of equity premium in this framework. We find that IRA preferences generate results that are more consistent with U.S. data for the equity premium, level of savings and portfolio shares, without assuming unreasonable levels of risk aversion. We find that the relative difference between the two risk aversions (how much more risk‐averse old agents are relative to the middle‐aged) matters more than the average risk aversion in the economy (how much more risk‐averse both cohorts are). Our findings are robust with respect to a number of model generalizations.     

Heteroskedasticity in Stock Returns

We use predictions of aggregate stock return variances from daily data to estimate time-varying monthly variances for size-ranked portfolios. We propose and estimate a single factor model of heteroskedasticity for portfolio returns. This model implies time-varying betas. Implications of heteroskedasticity and time-varying betas for tests of the capital asset pricing model (CAPM) are then documented. Accounting for heteroskedasticity increases the evidence that risk-adjusted returns are related to firm size. We also estimate a constant correlation model. Portfolio volatilities predicted by this model are similar to those predicted by more complex multivariate generalized-autoregressive-conditional-heteroskedasticity (GARCH) procedures.     

A value premium without operating leverage

The existing real options literature explains the value premium as a consequence of either operating leverage raising risk in low-demand states or industry-wide investment lowering risk in high-demand states. This paper presents a simple model in which a value premium arises solely from capacity constraints. Profit is more sensitive to demand shocks when there is excess capacity, and the book-to-market ratio is high, than when capacity constraints bind, and the book-to-market ratio is low. The option to adjust capacity weakens the value premium arising from assets in place, but does not eliminate it for a wide range of parameters.     

The Term Structure of Real Rates and Expected Inflation

Changes in nominal interest rates must be due to either movements in real interest rates, expected inflation, or the inflation risk premium. We develop a term structure model with regime switches, time‐varying prices of risk, and inflation to identify these components of the nominal yield curve. We find that the unconditional real rate curve in the United States is fairly flat around 1.3%. In one real rate regime, the real term structure is steeply downward sloping. An inflation risk premium that increases with maturity fully accounts for the generally upward sloping nominal term structure.     

On time varying risk premia in the foreign exchange market: An econometric analysis

A generic intertemporal asset pricing model is applied in an international setting to generate a (possibly time varying) risk premium in the market for forward foreign exchange. The model is fitted and statistical tests of its general specification are performed. These specification tests provide weak evidence against the model.     

Explaining the Rate Spread on Corporate Bonds

The purpose of this article is to explain the spread between rates on corporate and government bonds. We show that expected default accounts for a surprisingly small fraction of the premium in corporate rates over treasuries. While state taxes explain a substantial portion of the difference, the remaining portion of the spread is closely related to the factors that we commonly accept as explaining risk premiums for common stocks. Both our time series and cross-sectional tests support the existence of a risk premium on corporate bonds.     

The stochastic behavior of commodity prices with heteroskedasticity in the convenience yield

We document a new stylized fact regarding the dynamics of the commodity convenience yield: the volatility of the convenience yield is heteroskedastic for industrial commodities; specifically, the volatility (variance) of the convenience yield depends on the convenience yield level. To explore the economic and statistical significance of the improved specification of the convenience yield process, we propose an affine model with three state variables (log spot price, interest rate, and the convenience yield). Our model captures three important features of commodity futures—the heteroskedasticity of the convenience yield, the positive relationship between spot-price volatility and the convenience yield and the dependence of futures risk premium on the convenience yield. Moreover our model predicts an upward sloping implied volatility smile, commonly observed in commodity option market.     

Long- and short-term interest rates in a risky world

The paper develops and tests a general equilibrium model in which variability, or risk, affects the choice of portfolios. Our measures of variability include only the variability of unanticipated growth in monetary and non-monetary aggregates, and our tests use data ending with the change in Federal Reserve procedures in October 1979. We find that increased variability of unanticipated money growth raises demands for debt and money, and reduces the demand for real capital. Interest rates on both short- and long-term debt rise by a risk premium. We estimate the size of the risk premium before and after the October 1979 change, and we show that the change in Federal Reserve procedures moved the economy to a less efficient point.     

Is asymmetric mean-reverting pattern in stock returns systematic? Evidence from Pacific-basin markets in the short-horizon

This paper applies asymmetric nonlinear smooth transition generalized autoregressive conditional heteroskedasticity (ANST-GARCH) models to the analysis of mean-reversion and time-varying volatility in weekly index returns of the stock markets of nine countries in the Pacific-basin. It finds that the returns exhibit an asymmetric pattern of return reversals, viz., on average, a negative return reverts more quickly, with a greater magnitude, to a positive return than a positive return reverting to a negative one. The asymmetric pattern of return reversals is directly associated with the unequal pricing behavior on the part of investors. Following a negative return shock, investors do not appear to require any additional premium to the leverage effect; instead they actually neutralize the risk in the form of a reduced premium! The reduction in risk premium causes not only the current stock price to rise but also the realized negative return to revert faster with a greater magnitude.     

Inflation risk premia and the expectations hypothesis

We study the properties of the nominal and real risk premia of the term structure of interest rates. We develop and solve the bond pricing implications of a structural monetary version of a real business cycle model, with taxes and endogenous monetary policy. We show the relation of this model with the class of essentially affine models that incorporate an endogenous state-dependent market price of risk. We characterize and estimate the inflation risk premium and find that over the last 40 years the ten-year inflation risk premium has been has averaged 70 basis points. It is time-varying, ranging from 20 to 140 basis points over the business cycle and its term structure is sharply upward sloping. The inflation risk premium explains 23% (42%) of the time variation in the five (ten)-year forward risk premium and it plays an important role in help explain deviations from the expectations hypothesis of interest rates.