Pricing of Idiosyncratic Equity and Variance Risks∗ Elise Gourier† Princeton University October 24, 2014 Abstract This paper develops a parametric approach to study the equity and variance risk premia of individual stocks, based on the information contained in their underlying returns at different frequencies, and option prices. I introduce a continuous-time variation of the Capital Asset Pricing Model with stochastic volatility and jumps and estimate it using Bayesian filtering techniques over a time period including the recent financial crisis. I show that idiosyncratic equity risk is priced on short term horizons, but not on longer terms. In contrast, idiosyncratic variance risk is substantially priced in the cross-section of returns, for all terms considered. An analysis of sector Exchange Traded Funds reveals that most of them provide an interesting investment alternative for investors who are not willing to be exposed to non diversifiable risk. However, two sectors exhibit high priced idiosyncratic risk, namely the Energy and Financials sectors. JEL Classification: C38, C51, G12, G13. Keywords: Risk Premia, Idiosyncratic Risk. ∗ This paper was previously presented with the title ”Information Contents of Option Prices on Idiosyncratic and Systematic Equity Risks”. Special thanks go to Pierre Collin-Dufresne, Darell Duffie, Damir Filipovi´ c, Genevi` eve Gauthier, Jakub Jurek, Markus Leippold, Loriano Mancini and Norman Sch¨ urhoff for their helpful feedback. I also thank the participants of the Brown Bag Seminar at EPFL Lausanne, the eighth OxfordPrinceton Workshop, the Mathematical Finance Days at HEC Montreal, the eighth World Congress of the Bachelier Society and the ORFE Financial Mathematics Seminar at Princeton University for valuable comments. Financial support from the Swiss National Science Foundation (SNSF) is gratefully acknowledged. † Email: [email protected]. 1 1 Introduction The strong factor structure in the dynamics of asset returns has been widely documented since the introduction of the Capital Asset Pricing Model (CAPM) in the early sixties. The baseline CAPM predicts that the risk that drives a stock’s returns and does not come from the market factor, so-called idiosyncratic equity risk, can be diversified. Therefore it should not be priced in a perfect capital market. The associated risk premium, which reflects the compensation an investor requires to bear that risk, should thus be zero. However, empirical studies have suggested that this may not be the case in the presence of market imperfections, see, a.o., Malkiel and Xu (2001), Goyal and Santa-Clara (2003), Spiegel and Wang (2005), Fu (2009) and Garcia, Mantilla-Garcia, and Martellini (2011). Furthermore, recent papers, e.g., Herskovic, Kelly, and Lustig (2014) have highlighted a similar factor structure among the variances of the idiosyncratic components of returns, so-called idiosyncratic variances. Sch¨ urhoff and Ziegler (2011) further decomposed the idiosyncratic variance into a component that is linear in the variance of the market factor, referred to as common idiosyncratic variance, and a component that is specific to the firm, so-called true idiosyncratic variance. Measuring the risk premium attached to each source of risk is crucial to understanding the exposure of a portfolio, and to select appropriate investment and hedging strategies. Quantifying the idiosyncratic part of risk premia is, however, a difficult task. On the one hand, measuring the evolution of total risk premia requires knowledge on the conditional distributions of the asset returns under the empirical measure and an appropriate risk-neutral measure, which is challenging to acquire. On the other hand, filtering the idiosyncratic component of risk premia relies on assumptions on the dependence structure between stocks. Such assumptions often give rise to high-dimensional problems that are neither tractable nor easy to calibrate to market data. This paper develops a parametric approach to study the equity and variance risk premia of individual stocks. I introduce a continuous-time extension of the CAPM and estimate it using individual stocks’ returns, realized variances and option prices on every stock. I evaluate its performance in terms of pricing errors and forecasting accuracy. An analysis of the filtered idiosyncratic variance trajectory suggests that it contains valuable information on future returns. I show that idiosyncratic equity risk is priced on short time horizons, and idiosyncratic variance risk for all terms considered. In particular, the common idiosyncratic variance carries a risk premium which is significantly larger than zero whereas the risk premium attached to the true idiosyncratic variance is largely negative. 2 Finally, I relate the risk profile of single stocks to the one of the sectors they belong to, and show that certain sectors present are particularly appealing for investors. My framework assumes that individual stock returns’ dynamics consist of a systematic component which is function of the movements of a market factor, and an idiosyncratic component that solely depends on the firm’ characteristics. I introduce a continuous-time model in the spirit of CollinDufresne, Goldstein, and Yang (2012) and Christoffersen, Fournier, and Jakobs (2013). As risk premia strongly depend on higher order moments of the underlying returns, using jumps in the returns and variance process accommodates for the rich stylized facts of the empirical and risk-neutral distributions of the underlying stocks and market factor. High-frequency returns and options with short times-to-maturity are used to identify the jumps’ distributions. Options with wide ranges of maturities allow me to make inferences on the properties of the term structure of risk premia. Based on empirical evidence, my model accounts for idiosyncratic and systematic diffusive and jump drivers of the returns and allows for disentangling and analyzing their respective impacts. Furthermore, the model allows movements of the stochastic variance of single stocks to be correlated with movements of the market variance. The market factor is proxied by the S&P 500 and VIX indices. As my model belongs to the affine class of Duffie, Pan, and Singleton (2000), it is tractable and enables estimation to a cross-section of stocks’ returns and option prices over a relatively long time-series of data. Based on Bayesian filtering techniques, the estimation reconciles the vast information present in the data in order to quantify the idiosyncratic component of the asset returns’ dynamics, and better understand which risks are priced. The estimation procedure is based on the Auxiliary Particle Filter of Pitt and Shephard (1999) which, combined with a Maximum Likelihood estimation, yields time-consistent parameters as well as estimates of the distributions of unobservable processes and their jumps over time. I estimate the model over a time period of data that ranges from 2006 until the end of 2009, i.e., covering the financial crisis. This allows me to obtain accurate information on jumps, as these typically do not occur frequently and are hard to detect empirically. The model performance is examined over the subsequent time period spanning 2010 until the end of 2012. I show that the model is able to capture stylized facts that have been non-parametrically highlighted in the literature. In particular, estimation results confirm the relationships between the beta parameters and the risk-neutral variance and skewness of returns. Furthermore, I test the performance of the model in reproducing variance swap rates. I synthesize swaps from available options and regress 3 the resulting rates on model-implied rates for all stocks considered. Cross-sectional (Fama-MacBeth) and panel regressions indicate that the model accurately represents the synthesized data. I further challenge its reliability by evaluating how well it forecasts future variance swap rates. I compare the predictions it delivers to martingale predictions, whose best guess of the future rate is the current rate. Panel regressions reveal that the model significantly outperforms the martingale predictions for all future times considered. I perform a thorough analysis of the different risk sources in the variances of stock returns. Based on the estimated trajectories of the variance processes, I evaluate the contribution to total variance of, one the one hand, the variance of the market factor and, on the other hand, the idiosyncratic variance. I show that, for the stocks considered, the total variance is mainly governed by its idiosyncratic component in times of market calm, and that the market impact becomes substantial during turmoil periods. Idiosyncratic variances exhibit a strong factor structure that is similar to the one of the total variance, and justifies the decomposition of their dynamics into common idiosyncratic and true idiosyncratic movements. Furthermore, I perform a comparative study of the behaviour of the variances of single stocks in the Dow Jones with the sectors they belong to. This analysis uses returns and options’ data on SPDR Exchange Traded Funds. I find that most sectors have idiosyncratic variances that are smaller than those of the single stocks. Notable exceptions are, however, the Energy and Materials sectors, which have idiosyncratic variances that are close to 10% during times of low market volatility. This is also the case of the Financials sector after the beginning of the financial crisis. The level of idiosyncratic variance never returned to its pre-crisis level. In turn, the Consumer Staples, Industrials and Health Care sectors exhibit very low levels of idiosyncratic variances: close to zero outside the market volatility peaks, and around 10% during market stress. Knowledge of idiosyncratic variance is important because it can guide portfolio allocation. I point out that an investment over the period 2006-2012 in a dynamically rebalanced portfolio of stocks which have an idiosyncratic variance level in the highest quartile yields a higher Sharpe ratio of 6.37%, against 1.21% when one buys the stocks whose idiosyncratic variance is in the lowest quartile. This indicates that idiosyncratic variance contains information on future returns, suggesting that idiosyncratic variance risk may be priced in the cross-section of returns. My main empirical contribution is to provide an investigation of the equity and variance risk premia 4 of individual stocks. The use of filtering techniques allows me to reconcile the information present in the different data sources and quantify the priced idiosyncratic risk throughout the time period considered. I show that idiosyncratic equity risk is priced on a time horizon of one month, but not on terms that exceed six months. In contrast, idiosyncratic variance risk is substantially priced for all stocks and terms considered. A comparison to results obtained for sector Exchange Traded Funds reveals some interesting features. As a result to their small level of idiosyncratic variance, the Consumer Staples, Industrials and Health Care sectors carry very little idiosyncratic variance risk. Therefore they provide an interesting investment alternative for agents who are not willing to be exposed to non diversifiable risk. In constrast, the Energy and Financials sectors provide higher exposure to idiosyncratic risks than most of their components. Decomposing the price of idiosyncratic equity and variance risks for these sectors further reveals that a substantial part is due to tail risk. I base my analysis on a large body of literature that examines the equity and variance risk premia. Since the introduction of the Capital Asset Pricing Model (CAPM), many empirical studies have tried to explain expected returns of stocks and indices. Recent contributions include Ang, Hodrick, Xing, and Zhang (2006), Chang, Christoffersen, and Jacobs (2013), Bollerslev and Todorov (2011), Yan (2011) and Cremers, Halling, and Weinbaum (2013). The study of the variance risk premium (VRP) has also been the subject of a number of papers in the last decade, most of which focus on index returns. Among others, Bakshi and Kapadia (2003), Bakshi and Madan (2006), Amengual (2009), Adrian and Rosenberg (2008) and Bollerslev and Todorov (2011). Carr and Wu (2009), Driessen, Maenhout, and Vilkov (2009), Buraschi, Trojani, and Vedolin (2014), Han and Zhou (2013) extend the analysis of VRP to individual stocks using non-parametric analyses and emphasize its relation with the volatility level. The link between VRP and equity risk premium (ERP) has been further explored in the context of the search for return predictability. See, e.g., Bollerslev, Tauchen, and Zhou (2009), Drechsler and Yaron (2011) and Bollerslev, Morrone, Xu, and Zhou (2014). Many of the papers investigating the equity and variance risk premia rely on non-parametric approaches. The main advantage of these methods is that their results are model independent. However they must overcome the fact that risk premia are not observable using approximations and proxies. For example, the expectation of the future integrated variance under the empirical measure is typically approximated by the realized variance over the past days or weeks. The model I propose 5 aims to represent the stylized facts highlighted empirically, and enables computing risk premia and their components analytically. The remainder of this paper is structured as follows. Section 2 presents a preliminary data analysis. The model description and its properties are given in Section 3. Section 4 details the estimation procedure. Section 5 investigates the behaviour of idiosyncratic variance for individual stocks and sectors. Finally, Section 6 examines the estimated ERP and VRP and presents inferences made on the pricing of idiosyncratic risks. 2 Preliminary data analysis 2.1 Data The single stocks examined in this paper are the components of the Dow Jones Industrial Average index. Visa was excluded from the sample as it completed its initial public offering in March 2008. For every stock in the sample, the dataset includes daily dividend-adjusted prices obtained from CSRP, five-minute trading prices from the TAQ database as well option prices from OptionMetrics. The sampling period of high-frequency prices has been chosen to avoid adverse effects of microstructure noise while keeping a frequency which is high enough to make inference on the properties of jumps. All data span the time period from the 1st of March 2006 until the end of 2012. I eliminate options with missing bid/ask prices or zero bid prices, as well as options which have a negative bid-ask spread. I further remove options with zero open interest and those that violate the arbitrage conditions: C(t, τ, K) < S(t) and C(t, τ, K) > S(t) − Ke−r(T −t) . To account for the American feature of options, I follow Broadie, Chernov, and Johannes (2007) and calculate American volatilities implied from a binomial tree for all mid prices, and then treat the options as European, with an implied volatility equal to the one found. The error due to this adjustment is negligible for short-maturity options which have an early exercise premium close to zero, and increases with the maturity of options. To avoid beginning- and end-of-week effects, I follow standard practice and only keep Wednesday option prices. The S&P 500 combines the market capitalizations of the 500 largest US stocks, and therefore is a natural proxy for the market factor in the US market. It is complemented by the VIX index, 6 which represents the market expectation of the future volatility of S&P 500 returns over the next thirty days, and is often considered as a fear gauge of the markets. Options on both indices are liquidly traded. The dataset of underlying levels and options as well as its preliminary treatment is as described in Bardgett, Gourier, and Leippold (2014), extended to cover the period up to the end of 2012. 2.2 Factor structure of implied volatilities In addition to providing useful information on the individual stock returns’ distributions, I show in this section that options also contain information on the factor structure of stocks. I analyze the factor structure of implied volatility (IV) surfaces using Functional Principal Component Analysis (FPCA). While standard PCA decomposes the covariance matrix of a set of time-series to identify the main vectors of variation, FPCA performs a similar task with time-series of surfaces.1 The detailed procedure is described in Appendix A. I construct for every Wednesday in the sample a smooth estimator of the implied volatility surface IVt (m, τ ) over a grid of moneynesses m ∈ [mmin , mmax ] and times-to-maturity τ ∈ [τmin , τmax ] using available data, and a non-parametric Nadaraya-Watson estimator as detailed in H¨ardle (1992) and A¨ıt-Sahalia and Lo (1998). The outputs of the FPCA are a set of eigenmodes that represent the main directions of variation of the surface, and principal component processes that are the projection of the surface at every point in time onto the eigenmodes. The eigenmodes and principal component processes that result from the FPCA of the S&P 500 index are represented in Appendix A, in Figures 14 and 15. The first eigenmode represents the variation coming from the level of the IV surface, i.e. the upwards and downwards shifts of the entire surface. This mode is not completely flat, there is a slight upward tilt towards short maturities and smaller moneynesses and a slight downward tilt towards longer maturities and larger moneynesses. Furthermore, the mode is slightly decreasing as maturity and moneyness increase. This reflects the fact that deep out-of-the-money (OTM) put IVs tend to move more and deep OTM call IVs less 1 Similar analyses have been applied to indices by Skiadopoulos, Hodges, and Clewlow (2000), Cont and da Fonsecca (2002), Cont, da Fonsecca, and Durrleman (2002), Daglish, Hull, and Suo (2007). Furthermore, Christoffersen, Fournier, and Jakobs (2013) decompose the IV surface of single stocks into an affine function of moneyness and time-to-maturity. Standard PCA is then applied to the time-series of loadings. This procedure is a sub-case of the one I apply, in which the first direction of variation of the IV is affine in the moneyness and the second is proportional to the time-to-maturity. I allow eigenmodes to be polynomial functions of both moneyness and maturity. 7 than other IVs. The second mode is a skew mode. OTM put IVs move in opposite directions from OTM call IVs. The mode changes sign at the ATM level. Overall magnitudes tend to decrease as the time-to-maturity increases. The third mode is a term structure mode. Short-term IVs move in the opposite direction from long-term IVs. The magnitude tends to decrease as the moneyness increases. Finally, the fourth mode is a convexity mode. Deep OTM put and call IVs tend to fluctuate more than ATM option IVs. These findings are consistent with those of Cont and da Fonsecca (2002). They find that the third mode is the convexity mode, instead of the term structure mode. But this is likely due to the fact that they use a shorter time-series of data. The same analysis is conducted on IV surfaces of single stocks. The resulting modes as well as the percentages of variance they explain are described in Table 1. The first three eigenmodes are usually the same as those found for the S&P 500. In some cases the term structure mode explains more variation than the skewness mode. Overall, the first mode explains a large percentage of the variation of the surfaces, on average 97.5%. The corresponding principal component process is highly correlated with the one of the S&P 500 surface decomposition, with a correlation of 91.6% on average. The second and third eigenmodes are also significantly correlated with the corresponding eigenmodes of the S&P 500 decomposition, with respective average coefficients of 51.6% and 42.6%. Functional PCAs therefore indicate a strong factor structure of the main driver of IV surfaces, i.e., the level of the surface. The other drivers, which roughly represent the skewness and term structure of the surfaces, also exhibit a large positive correlation with the corresponding market principal components. However, I interpret the fact that this correlation is always substantially lower than 1 as an indication of firm specific variation in IV. These results are consistent with those of Christoffersen, Fournier, and Jakobs (2013). 2.3 Factor structure of high-frequency returns High-frequency data contain valuable information on the fine structure of data. In particular, diverse measures of variation of log-price increments have been introduced that enable disentangling the contribution of the diffusive and jump components of the dynamics of returns.2 In this section, I use 2 See for example Andersen, Bollerslev, Diebold, and Labys (2003), Barndorff-Nielsen and Shephard (2004) and Barndorff-Nielsen and Shephard (2006) 8 high-frequency data to analyze the potential factor structure of some of these measures.3 For each stock I calculate the daily Realized Variance (RV), which captures the total variation of high-frequency returns over a day, and can be decomposed into the Continuous Variation (CV), which represents the variation due to continuous movements of the returns, and the Jump Variation (JV) which captures discontinuous movements of returns. For definitions and convergence properties, see, e.g., Bollerslev, Todorov, and Li (2013). I apply a PCA to these measures.4 The same analysis is performed after taking their n-day moving averages, with n ∈ [3 180]. The percentage of variance explained by the first principal component as a function of n is displayed in Figure 1. Using a larger n leads to the first component explaining a larger percentage of the variance of all measures, with that percentage being very close to 100% when the 6-month moving average is considered, except for the jump variation measure. Along the same line, a smaller number of factors are needed to explain the total amount of variation when n increases. I interpret this result as an indication that the factor structure explains the overall tendencies of variation measures, whereas the daily fluctations are mainly caused by firm-specific events. The much smaller percentage of variation of the jump measure explained by the first components indicates that most jumps are idiosyncratic, and that the factor structure of the diffusive movements is much stronger than the one of jumps. These results are in line with Bollerslev, Todorov, and Li (2013), who find that the number of filtered idiosyncratic jumps in stocks that belong to the S&P 500 exceeds the number of systematic jumps for all the stocks contained in their sample. I propose to represent the factor structure of asset returns using a parametric modeling approach. Most studies using high-frequency data or option prices use non-parametric or semi-parametric approaches, which present more flexibility in analyzing the data and do not face the challenge of estimation. However, with such approaches it is only possible to draw inferences, e.g., they cannot be used for out-of-sample exercises, which are important parts of this paper. 3 Luciani and Veredas (2012) and Barigozzi, Brownlees, Gallo, and Veredas (2014) introduce a dynamic factor model for realized volatilities. 4 A log-transformation is applied to the RV. 9 3 Model 3.1 Model setup Let (Ω, F, {Ft }t≥0 , P) be a filtered probability space satisfying the usual assumptions, where P denotes the empirical measure. I denote by M = (Mt )t≥0 the value process of the market factor. Its dynamics under P are specified as follows. q dMt M M (P) M (P) P ZtM = (rt − λM (vtM − 1] + γtM (vtM vtM + (eZt − 1)dNt − , mt )E [e − , mt ))dt + − dWt Mt− ! q κM M (P) M (P) M (P) v M M (P) M m dvt = κv dt + σ m − v vtM + yt dNt − − dBt v t M (P) t κv (P) M (P) M√ ¯ M (P) dmt = κM (θ − mt )dt + σm mt dB m t (1) (2) (3) The risk-free rate rt is assumed to be a deterministic function of time. Price returns are driven by M (P) a Brownian motion Wt M (P) and a Poisson process Nt . The continuous part of the returns’ vari- ance is governed by the process (vtM )t≥0 , which mean-reverts towards a stochastic central tendency M (P) (mt )t≥0 , up to a scaling factor. Its mean-reversion speed is controlled by κv . The parameter κM v corresponds to the speed of mean-reversion of the variance under an equivalent martingale measure Q. The stochastic central tendency mean-reverts itself towards a fixed long-run mean θM (P) , with speed M (P) κm . Jumps in the returns process occur simulateneously with jumps in the first variance factor vtM , M M M M 5 with an intensity that is affine in the two variance processes: λM (vtM − , mt ) = λ0 + λ1 vt− + λ2 mt . The sizes of jumps in the returns are assumed to be independent and identically distributed following a normal distribution. Jumps in the variance are assumed to be exponentially distributed. This implies that the variance can only jump upwards and prevents it from becoming negative. The leverage effect that impacts the market factor is represented by the correlation coefficient ρM defined such that dhW M (P) , B M (P) it = ρM dt. The model for individual stocks is a continuous-time extension of the CAPM.6 I separate the impact of 5 Based on a non-parametric study, Bollerslev and Todorov (2011) argue in favor of time-varying jump intensities and a tendency for fatter tails in period of high overall volatility. 6 The model is related to the one of Collin-Dufresne, Goldstein, and Yang (2012), but additionally features idiosyncratic jumps and stochastic volatility. The framework which is closest to mine is the one of Christoffersen, Fournier, and Jakobs (2013), who calibrate a diffusive model to a cross-section of stock returns and option prices. There are 10 the market factor into two contributions. On one side the diffusive random variation of single stocks’ j returns is dependent on the Brownian motion that drives market returns through the coefficient βdif f. On the other side discontinuous movements in the market returns can also translate into jumps in j single stocks’ returns, though the coefficient βjump . A jump of size ZtM in the market log level triggers a jump of βjump ZtM in the individual log stock price.7 This allows disentangling the effects of both market drivers on single stocks’ returns. Under P, the dynamics of firm j’s dividend-adjusted stock prices Stj are given by: dStj Stj− = (r + γtj )dt j + j βdif f q q j j M (P) j(P) j(P) M vt− dWt + vtj− dWt + (eZt − 1)dNt − λj (vtj− )EP [eZt − 1]dt M M (P) + (eβjump Zt − 1)dNt dvtj = βvj dvtM + κj(P) v κjv j(P) κv j M P βjump Zt − λM (vtM − 1]dt − , mt )E [e ! q θj − vtj − dt + σvj − j(P) vtj dBt (4) j(P) + ytj dNt . (5) I account for the idiosyncratic leverage effect: dhW j(P) , B j(P) it = ρj dt. In line with the preliminary data analysis, I assume that idiosyncratic returns and variance can jump. As for the market factor, jumps occur in both processes simultaneously, with an intensity that is affine in the variance process: λj (vtj− ) = λj0 + λj1 vtj− . The sizes of jumps in the returns are assumed to be normally distributed with mean µj(P) and variance (σ j(P) )2 . Jumps in the variance follow an exponential distribution with mean ν j(P) . The model allows for two new features. On the one hand, it disentangles the respective impacts of the diffusive and jump components of the market factor on individual stocks. Such differentiation is justified by the notion of crash aversion introduced by Bates (2008), who argues that the investors some major differences however between their work and mine. First, they assume that the idiosyncratic variance is independent from the market variance. An examination of the idiosyncratic variances of stocks suggests that a richer factor structure would be needed, as further advocated by Serban, Lehoczky, and Seppi (2008), Sch¨ urhoff and Ziegler (2011) and Herskovic, Kelly, and Lustig (2014). My model accounts for this and decomposes idiosyncratic variance movements into a common and a true idiosyncratic component. Second, they assume that idiosyncratic variance risk is not priced. In other words, the variance risk premium of single stocks is assumed to be zero. Although it has been shown to be smaller in magnitude than the variance risk premium of the index, there is empirical evidence for a non-zero variance risk premium in individual stocks. Third, they estimate the trajectory of the unobservable spot variance of the index and of single stocks using a least-square algorithm, i.e., its dynamics are not ensured to be consistent with the specified model. The use of Bayesian methods allows me to have an estimation which guarantees that the filtered trajectory of the spot variance is consistent with the model specification. Last, their model does not include jumps, which have been shown to be important, especially during the financial crisis, to fit option prices, see, e.g., Bakshi, Cao, and Zhong (2012). 7 Based on a model selection exercise, Bakshi, Cao, and Zhong (2012) propose to use a model with jumps in the returns and in the volatility of individual stocks. 11 treat jump and volatility risks differently. For example, an investor may want to hedge tail risk, in j which case he will find stocks with a larger βjump more attractive. Both volatility and jump risks are priced in the cross-section of returns, as has been shown by Cremers, Halling, and Weinbaum (2013). On the other hand, my model allows the idiosyncratic variance of individual stocks to be correlated with the market variance. Sch¨ urhoff and Ziegler (2011) and Herskovic, Kelly, and Lustig (2014) show that the idiosyncratic variance of individual stocks can be decomposed into a true idiosyncratic component that is firm-specific and a common idiosyncratic component, which depends on the market variance. Therefore I divide the movements of the variance into two parts. The first one measures the impact of the market variance on the idiosyncratic variance. It is linear in βvj . Therefore, βvj represents the exposure of the idiosyncratic variance to the market variance. This first part is referred to as the common idiosyncratic variance. The second component of the idioyncratic variance is driven j(P) by a firm-specific Brownian motion Bt j(P) and a Poisson process Nt . It is referred to as the true idiosyncratic variance, as its drivers are assumed to be independent from the drivers of the market variance. Such representation preserves the affine structure of the model. The model can be easily extended to multiple factors driving underlying stocks’ returns. Several factors have been proposed in the asset pricing literature. The size and value factors of the popular Fama-French three-factor model account for the extra risk present in small companies’ stocks and value stocks. However, a regression of the returns on the three Fama-French factors over the time period considered reveals that the betas associated with the SMB (Small market capitalization Minus Big) and the HML (High book-to-market ratio Minus Low) are close to zero. Histograms of the point estimates of the two betas are provided in Figure 2. Furthermore, adding factors in the proposed setup requires additional parametric assumptions on their dynamics, and involves further model and estimation error. Finally, traded derivatives’ prices would be needed to estimate the risk premia of these factors. Such generalization would therefore be challenging to apply in practice. One limitation of my model is that the beta coefficients are assumed to be constant in order to preserve the affine structure of the setup. This assumption is, however, justified by the time-series of data considered. Adrian and Franzoni (2009) show that the beta in its traditional sense varies over time when looking at a long time-series of data, typically including several decades. The advantage of such exercise is to dispose of a sufficient amount of data points. However, various issues such 12 as the non-stationarity of the data may arise in this case. As I work with options, the amount of available data is already very large and is sufficient to draw inferences for the recent years covering the financial crisis, while keeping the betas constant over this time horizon. 3.2 Risk premia specification Due to incompleteness of the market, the risk-neutral measure is not unique. Following standard practice, I parameterize the pricing kernel Lt defined in equation (6), which is then calibrated to the market. The corresponding risk-neutral measure is denoted by Q. Lt can be decomposed into two components which respectively contain the market prices of risk of the diffusive and jump processes that play a role in the dynamics of assets returns: −rt Lt = e dQ f jump = e−rt Ldif Lt . t dP Ft (6) The diffusive component of the pricing kernel is equal to Z f Ldif t = exp t Λ0s dWs 0 1 − 2 Z t Λ0s Λs ds 0 where Wt is the vector of diffusive random processes that drive asset returns at time t and Λt is the vector of premia attached to every element of Wt , assumed to be proportional to the volatility levels: Wt0 = Λ0t = M (P) Wt ηM ¯ M (P) , W j(P) , B j(P) , B t t t q p p M (P) M (P) κM κM j M M v −κv m −κm vt , mt , η vtj , σM σM M (P) , Bt p vtM , v m j(P) κjv −κv σvj q vtj . (7) The parameters without superscript (P) in equation (7) either correspond to the Q-counterpart of the P-parameters, or are invariant under both measures. This specification allows for non-zero equity and variance risk premia in the market factor and in individual stock returns. The affine structure of the model is preserved under Q, so that options can be efficiently priced using Fourier methods. 13 The jump component Ljump accounts for different mean and variance of jumps under P and Q. For t the sake of identification, the intensity of jumps is assumed to be equal under both measures: M (P) Z t Z Y φM (Q) (Z M ) n M M M (P) M (Q) = exp λ (vs , ms ) φ (z) − φ (z) dz ds φM (P) (ZnM ) 0 R n=1 Nt Ljump t j(P) Nt Y Y φj(Q) (Znj ) j∈{1,...,J} n=1 φj(P) (Znj ) Z t Z exp 0 λj (vsj ) φj(P) (z) − φj(Q) (z) dz ds R where J is the number of individual stocks considered. The functions φM (ZnM ) and φj (Znj ) refer to the normal density function, with parameters equal to the mean and variance of jump sizes in the market factor and single stock j, under the specified measure. I make the assumption that the leverage and the beta coefficients are the same under the riskneutral and objective measures. The latter assumption is consistent with Serban, Lehoczky, and Seppi (2008), who find estimates which are statistically close under both measures. Under this specification of the pricing kernel, the market equity risk premium (ERP) coefficient γtM present in equation (1) is equal to the sum of a diffusive contribution that is proportional to the market variance level, and a jump contribution that reflects the different jump size distributions under the measures P and Q: M M M M γtM = η M vtM (vt− , mt ) EP [eZt − 1] − EQ [eZt − 1] . − + λ Similarly, the single stock’s ERP coefficient γtj present in equation (4) can be decomposed into a diffusive and a jump contribution. Each of them is itself the sum of an idiosyncratic component and j j a market component, whose impacts are quantified by βdif f and βjump : j M M γtj =η j vtj + βdif f η vt j j M P βjump ZtM − 1] − EQ [eβjump Zt − 1] . + λj (vtj− ) EP [eZt − 1] − EQ [eZt − 1] + λM (vtM − , mt ) E [e Under this specification of the change of measure, the dynamics of the market factor and individual returns are given in Appendix C. 14 3.3 Properties of the model Due to the affine structure of the model, option prices are available in closed-form and involve the characteristic functions of returns, which are known up to the resolution of Ordinary Differential Equations (ODEs). Assuming the existence of derivatives on the market factor, the characteristic function of market returns is given in Bardgett, Gourier, and Leippold (2014). The one of single stocks’ returns can be derived similarly. Proposition 3.1. The Laplace transform of the single stocks’ log returns S˜tj = log Stj is exponential affine in the factor processes: h i ˜ ΨS˜T (t, s˜t , vtj , vtM , mt ; ω) := EQ eωST |Ft j ˜ M +χ(T −t)·m = eα(T −t)·St +β(T −t)·vt +γ(T −t)·vt t +η(T −t) where the coefficients α, β, γ, χ and η are functions defined on [0, T ] by ODEs presented in Appendix D and ω ∈ C is chosen so that the conditional expectations are well defined. The availability and tractability of the Laplace transforms are desirable features, as they allow using Fourier methods to calculate option prices in a fast and efficient manner. Another important property of the model is that risk premia are available in closed-form. The integrated equity risk premium (IERP) is defined as follows8 : 1 IERP (t, T ) = T −t j " EPt log STj Stj " # − EQ t log STj Stj #! . (8) It represents the difference between the expected return made by an investor who buys stock j at time t and keeps it until time T , under the empirical and risk-neutral measures. It is composed of two parts. On the one hand, the diffusive part depends on the market price of idiosyncratic risk η j and on the price of risk of the market factor, η M . On the other hand, the jump component depends j j j j S −S ST −St This definition is equivalent to the usual definition IERP j (t, T ) = T 1−t EPt T j t − EQ up to the j t St St " # " #! 2 j j 2 j j ST −St ST −St convexity adjustment O EPt − EQ . In the following, the notation Et [.] is used in place of j j t 8 St St E[.|Ft ]. 15 on premia attached to the mean and variance of the jump sizes. The integrated variance risk premium (IVRP) reflects the amount that an investor would be willing to pay to be hedged against the fluctuations in an asset’s variance. It is defined as follows: IV RP j (t, T ) = i h i 1 Ph j j Q Et QV[t,T − E QV t ] [t,T ] T −t (9) where QV[t,T ] denotes the quadratic variation of the log price process, i.e., the sum of the integrated variance of returns and the squared jumps in the time interval considered. As a result of the affine property of the model, the IERP and IVRP are available in closed-form and can be expressed as linear functions of the latent variance processes. Details on the calculation of the IERP and IVRP are available in Appendix E. Finally, the model is consistent with empirical facts highlighted in the literature on the relationship between the beta and risk-neutral moments of the conditional distribution of log-returns. Duan and Wei (2009) find that firms with higher betas tend to have a high level of risk-neutral variance. In my j 2 M model, the risk-neutral variance rate can be decomposed into a diffusion part vtj− + (βdif f ) vt− that j 2 j j M 2 M M j j j 2 2 M 2 increases with βdif f , and a jump part (σ ) + (µ ) λ (vt− )+(βjump ) (σ ) + (µ ) λ (vt− , mt ) j that increases with βjump . Appendix F shows that the total risk-neutral variance of stock j over [t, T ] also increases in both betas. Furthermore, Dennis and Mayhew (2002) and Duan and Wei (2009) find that higher beta firms have more negatively skewed risk-neutral distributions. In my model and as detailed in Appendix F, the skewness rate can be decomposed into a market effect and an idiosyncratic component. The market component increases in absolute value proportionally to (βdif f )3 , and is negative. The idiosyncratic component is closer to zero. Therefore my model reflects the findings of Dennis and Mayhew (2002) and Duan and Wei (2009). 4 Estimation I estimate the model using data from 2006 until to 2009, covering the financial crisis. This period is subsequently referred to as the in-sample period. The model performance is examined on the 16 subsequent time period (out-of-sample period) spanning 2010 up to the end of 2012. Table 2 reports the amount of options included in the in- and out-of-sample periods for every stock. As the number of traded options tends to increase over time, for many stocks it is higher in the out-of-sample period than in the in-sample period, which is a challenge for the model. 4.1 Estimation method ?? I estimate the model in two steps. The first step consists in estimating the parameters of the market equations (1) - (3). I reconcile the dynamics of the S&P 500 and VIX indices following the estimation procedure outlined in Bardgett, Gourier, and Leippold (2014). The affine characteristics of the model allows me to use the Fourier Cosine method introduced by Fang and Oosterlee (2008) to calculate the prices of VIX options. My procedure is based on the Auxiliary Particle Filter of Pitt and Shephard (1999) which, combined with a Maximum Likelihood estimation, yields time-consistent parameters as well as estimates of the distributions of unobservable processes over time and their jumps.9 Given the parameters and latent processes driving the market factor 10 , the second step uses a similar algorithm to estimate the parameters and filter the processes that drive every individual stock. In this second step, all estimations can be run in parallel, making the procedure particularly efficient. I cast the problem in a state-space form, which consists of a transition equation and three measurement equations. The transition equation is an Euler discretization of the SDEs satisfied by the variance process of the individual stock prices under P, on a uniform time grid of M + 1 points t ∈ {t0 = 0, t1 = ∆t, ..., tM = M ∆t}, M ∈ N? so that M ∆t corresponds to the end of the period considered. For t ∈ {0, ..., M − 1}: ∆vtj = βvj ∆vtM + κj(P) v κjv j(P) κv ! j θ − vtj ∆t + σvj q j(P) vtj ∆Bt j(P) + yt j(P) ∆Nt . The measurements consist of log-returns, option prices and daily values of the RV. The first measurement equation is obtained using the Euler discretization of the dynamics of log-returns. The second 9 This procedure allows obtaining at each point in time an estimate for the density of the latent factors, consistent with the specified stochastic differential equation (SDE). In that sense it provides a significant improvement over the typically used least-square estimation, see e.g, Christoffersen, Fournier, and Jakobs (2013), where the estimation treats the unobservable factors as parameters. 10 At every time t, I use the empirical mean of the filtered density of these factors as point estimate. 17 matches the logarithm of model-implied option prices to market data. It is a vector equation. Its dimension is equal to the number of options that are traded at time t. The error term is assumed to follow a normal distribution centered at 0, with a heteroskedastic variance that is exponential affine in the bid-ask spread, the log-moneyness of the option and its time-to-maturity. The last measurement equation expresses the variance rate as an affine function of the realized variance, following Wu (2011). The innovations are assumed to be normally distributed centered at zero, with variance proportional to vtj to account for the fact that the error made when estimating the variance tends to increase with the variance level. The parameters driving the jump distribution under the empirical measure were found hard to estimate precisely. Therefore, they were estimated in a preliminary investigation of high-frequency returns and fixed throughout the particle filtering exercise. The algorithm used to estimate them is outlined in Appendix B. Estimated intra-day jumps were aggregated on a daily basis, so that the empirical mean and standard deviation of daily jumps could be calculated. 4.2 Estimation results The estimation performance is evaluated by examining root mean-square errors (RMSEs) and relative errors, as well as the evolution of sequential likelihoods in- and out-of-sample. RMSEs are reported in Table 3. For the sake of conciseness, the other performance measures are not reported but are available upon request. There is a slight loss of quality in the estimation of deep OTM options. This is not surprising as the tails of the risk-neutral distribution are typically hard to estimate. In addition, short-term options tend to be better fitted than longer-term options. This could be improved by making the mean reversion level of the idiosyncratic variance stochastic. Parameter estimates as well as their standard errors are displayed in Table 4. The mean size of return jumps under P is very close to zero, which is in line with Yan (2011). Under the risk-neutral measure, it tends to be more negative, consistent with a positive jump equity risk premium. Furthermore, the risk-neutral speed of mean reversion of the variance process is always significantly lower than its empirical counterpart, which pulls the variance risk premium towards negative values. j The beta coefficients are reported in Table 5. Stocks are grouped by industry. The diffusive beta βdif f varies between 0.450 for Procter & Gamble and 1.221 for Goldman Sachs. Companies specialized in 18 j financial services have the highest values of βdif f . As those firms were at the core of the financial crisis, this result was expected. Note that they are not the companies with the largest market capitalizations, as could be expected because the S&P 500 is capitalization-weighted. For example, j Johnson & Johnson (JNJ) has a low βdif f = 0.497 but one of the largest market capitalizations. Companies specialized in consumer staples, such as The Coca-Cola Company (KO), tend to have a relatively low exposure to diffusive market movements. The exposure of a stock to the market is directly linked to its risk-neutral variance, as Figure 3 illustrates. As a model-free measure of the risk-neutral variance, I use the two-month at-the-money (ATM) IV. Its evolution is displayed for three stocks on the left panel of the figure, over the time period March 2006 - December 2012. The estimated diffusive betas of these stocks are respectively: 0.497 for JNJ, 0.670 for IBM and 1.221 for GS. The graph clearly indicates that the overall level of j IV increases with βdif f . In the absence of jumps, my model specification implies that the risk-neutral j variance is proportional to the square of βdif f . The right graph of Figure 3 represents the median j of the two-month ATM IV versus the estimated value of βdif f squared across stocks. As expected, the graph indicates a monotonic relationship between the two quantities. I do not find any evidence j that the risk-neutral variance is increasing in the jump exposure coefficient βjump , which is justified by the fact that the variance is mainly driven by its continuous part. Similarly, I examine the relationship between the returns’ implied skewness and the betas. The left graph of Figure 3 suggests that the magnitude of the IV peaks in times of crisis also increases with the coefficient βdif f . As a model-free proxy of the risk-neutral skewness, I use the average difference between the 95% and the 5% quantiles of the two-month ATM IV. Figure 4 represents this value for 3 every stock versus the point estimate of βdif f . This graph indicates a monotonic relation between the two quantities, in agreement with theory. 4.3 Out-of-sample performance: test on variance swaps As a consequence of the affine structure of the model, variance swap (VS) rates are available in closed form. The rate with term τ for company j is given by: VSj,model t,τ = EQ t t+τ Z VarRate (u)du j t 19 (10) where the variance rate is given by: j 2 M VarRatej (t) =vtj− + (βdif f ) vt− j )2 (σ M )2 + (µM )2 λM (vtM + (σ j )2 + (µj )2 λj (vtj− ) + (βjump − , mt ). 4.3.1 (11) Out-of-sample pricing To evaluate the out-of-sample performance of the model, I compare synthesized VS rates with maturity one month to model-implied rates. Every week I synthesize VS using a portfolio of OTM options as described in Carr and Wu (2009). The resulting VS rates are denoted by VSj,data . The replication procedure assumes that the underlying stock does not jump. If this assumption is not satisfied, the error is dependent on the compensator of the jump component. Therefore, to make the two quantities comparable, I only consider the continuous part of the model-implied VS rate. I perform a linear regression with the synthesized one-month VS rate on the left hand-side and its model-implied counterpart on the right hand-side. The error term includes different potential sources of discrepancies between the two quantities. First, the replication involves interpolation and extrapolation procedures that take as input a finite number of options with different maturities and moneynesses. The amount of available options varies from week to week, and yields as output the implied volatilities of options defined on a grid of moneynesses, with maturity one month. The quality of the replication depends on the number of options with maturity close to one month that are available on a specific date, and on the range of their moneynesses. Second, there is inherent noise in the data due, for example, to the bid-ask spread, that is further reflected in the error term. Finally, the model is calibrated to a large amount of datapoints, and the estimation is clearly subject to model specification error as well as estimation error. The intercept should be zero if there is no systematic bias in the estimation. The slope parameter reflects the ability of the model to capture the amplitude of the movements of VS rates, it should be one if the model perfectly replicates the magnitude of the data on average. Non-systematic errors will be reflected in the error term. I consider two types of regressions in Table 6: repeated cross-sectional regressions (Fama-MacBeth) and a pooled panel regression. For the cross-sectional regressions, I report the time-series mean of the coefficient estimates and the R2 . The standard errors are calculated using the Newey-West procedure to account for autocorrelation, with eight lags. Cluster-robust standard errors are used in 20 the panel regression following the method of Cameron, Gelbach, and Miller (2011), to account for cross-sectional correlation and time-series auto- and cross-correlations. Both cross-sectional and panel regressions yield estimates of the intercept that are close to zero, which indicates that the model does not present a bias in its representation of one-month VS rates. Estimates of the slope parameter are both slightly smaller than 1. Therefore the model tends to underestimate the magnitude of VS rates. The hypothesis that the model correctly prices VS, i.e., that the intercept is zero and the slope coefficient one, has a p-value of 96% when the regression is run every week, and 87% when it is run for the whole panel at once. The average R2 from the cross-sectional regressions is 82%, it goes down to 70% in the panel regression. In summary, the model fits suynthesized VS rates remarkably well. 4.3.2 Forecasting I further evaluate the out-of-sample performance of the model in forecasting VS rates. The modelimplied conditional expectation of a time-u VS rate is EPt [VSu ]. I regress the ex ante VS rate at time u on this expectation, using cross-sectional and panel regressions. I further challenge the model by comparing the predictions it delivers to a prediction based on the current VS rate at time t. The latter method is referred to a as martingale prediction, it assumes that the VS rates follow a random walk, in which case the best guess of future rate that it gives is the rate of today. Given the high persistence in VS rates dynamics, the martingale prediction is a rather challenging benchmark. If the forecast is accurate, the intercept of the regressions should be zero and the slope parameter one. I test this hypothesis and compare the p-values delivered by both prediction methods, for different future times u. Table 7 reports the results of the regressions for three values of u − t: one week, one month and one month and a half. The R2 of the regression using the model prediction is comparable to the one using the martingale prediction, for all values of u − t. As expected, the R2 decreases with u − t and is higher for the cross-sectional regressions than for the panel regressions. The p-value of the null hypothesis is close to 1 for u − t equal to one week with the model prediction. The martingale prediction, in turn, yields a p-value of only 0.10 in the panel regression. For u−t equal to a month and six weeks. the p-values of the cross-sectional regressions remain high, around 0.8, for both the model and the martingale prediction. The panel regressions, in turn, highlight the better performance of 21 the model predictions, with a p-value of 0.19 against 0.05 for u − t equal to one month and of 0.24 against 0.03 for u − t equal to six weeks. To summarize, the model accurately predicts VS rates and outperforms a martingale model. 5 5.1 Idiosyncratic variance Descriptive analysis The total variance swap rate at time t, given by equation (11), decomposes into a diffusive part vtj− + j j 2 M j 2 j 2 j j 2 M 2 (βdif f ) vt , which is measure-independent, and a jump part [(σ ) +(µ ) ]λ (vt− )+(βjump ) [(σ ) + (µM )2 ]λM (vtM − , mt ), which is different under P and Q because of the jump risk premia. Under P, the diffusive variance represents on average 86% of the total variance rate, and 85% under Q. Figure 5 displays the decomposition of the diffusive and jump parts of the variance rate into an idiosyncratic component and a component that comes from the effect of the market factor, for a typical stock. The impact of the market factor is very low in times of low market volatility, i.e. at the beginning of the sample period. The variance rate is then almost solely driven by the idiosyncratic variance of the firm, which is typically much higher than the market variance due to the averaging effect in the market portfolio. In turn, during volatility peaks, the market factor has a stronger j influence on the assets’ total variance, which is scaled by the βdif f parameter. For a typical stock, the influence of the market factor is of the same order of magnitude as the idiosyncratic variance during these peaks, causing the variance to be multiplied by a factor of approximately 2. The decomposition of the jump part of variance rates follows a similar pattern. The main difference however is that the market component usually dominates the idiosyncratic component after the first volatility peak. The preliminary data analysis highlighted a strong common component in single stocks’ variances. This phenomenon is also striking for their idiosyncratic components. Applying PCA to the total instantaneous variance rate and its idiosyncratic component, I find that the first principal component explains more than 92% of the variation of the total variance rate, and the first three components more than 97%. The numbers are only slightly lower for the idiosyncratic variance, as the first component explains 81% of its variation and the three first components more than 92%. These 22 results are generally in line with Herskovic, Kelly, and Lustig (2014)11 . The analysis of Herskovic, Kelly, and Lustig (2014) further suggests that idiosyncratic variance varies with the size of the company and the industry it belongs to. As the methodology I use to estimate the idiosyncratic variance is completely different from theirs, it is worth revisiting their results. To analyze the influence of the company’s size on its idiosyncratic variance, I sort the considered firms by their market capitalization as of end of 2012 and divide them into five buckets. Into each of these buckets, I calculate the average total diffusive and jump variance rates across time. Taking the variance rate of the bucket of firms with the smallest market capitalizations as a reference process, I regress the time-series of the average variance rates in the other size buckets on the reference time-series. Table 8 summarizes the results of the regressions. They indicate that firms with the largest market capitalization have a smaller variance rate on average. Exceptions are companies that suffered more from the financial crisis, such as GE, which presents higher variance rates than the other companies in the bucket. I conduct the same analysis on the diffusive idiosyncratic variance rates and find the same pattern, as shown in Table 9. As parameter estimates do not seem to indicate that companies of smaller size tend to have a larger exposure to the market factor, I conclude that the idiosyncratic variance is responsible for the fact that the total variance rate decreases when the size of the company increases. This ordering does not hold anymore for the true idiosyncratic variance, which pinpoints the common idiosyncratic variance as the determinant of this phenomenon. Herskovic, Kelly, and Lustig (2014) suggest that the industry also has an impact on the idiosyncratic variance. To examine this assertion, I repeat the estimation exercise using data which are industry related. SPDR Exchange traded funds (ETF) were introduced in 1998 and track the performance of the Global Industry Classification Standard sectors of the S&P 500. Every fund is a portfolio of the components of the index in the corresponding sector. American options started trading on the funds and knew a fast-growing success. A summary of the data available on sector ETFs is provided in Table 10. All options are of American type; the dataset is treated similarly to the options on single stocks. Figure 6 represents the evolution of the total idiosyncratic variance v j , as estimated by the particle 11 Herskovic, Kelly, and Lustig (2014) use a completely different methodology to obtain these results. They calibrate a factor model to returns and compute the idiosyncratic variance as the variance of the residuals. 23 filter, for each sector considered and the stocks of the Dow Jones that belong to this sector. The variance levels are compared to the trajectory of the market factor. Until the end of 2007, most sectors have idiosyncratic variances which are comparable to the one of the market factor, between 0 and 3%, and lower than the one of the considered stocks. The variance of a portfolio is composed of a weighted average of the individual variances, where the weights are equal to the square of the weights that form the portfolio, and a term that corresponds to the covariances. If the correlation between the stocks in the portfolio is not too large, the covariance term is close to zero, and it is common that the portfolio’s variance be smaller than the individual variances. The Energy and Materials sectors distinguish themselves from others because they have higher idiosyncratic variances, around 8%. As the variance tends to increase when the market capitalization of the stock decreases, it is reasonable to assume that most stocks of the S&P 500 that have not been represented because they do not belong to the Dow Jones, have larger levels of idiosyncratic variance that the stocks considered which are in the same sector. In the Energy sector, the two stocks considered, Exxon Mobil Corp (XOM) and Chevron Corp (CVX), represent around 30% of the holdings of the ETF. DuPont (DD) represents around 10% of the holdings of the Materials sector’s ETF. Therefore, the large idiosyncratic variance of the Enery and Materials sectors in 2006 and 2007 may be explained by a larger variance of the smaller stocks in the portfolios. At the end of 2007, the variance of the Financials sector starts increasing swiftly, and reaches 15% mid 2008. Such early increase is specific to that sector and does not occur in any other sector. During the market variance peak, all sectors are exhibit increases in idiosyncratic variance. However, the Consumer Staples, Industrials and Health Care sectors are only marginally affected. The maximum level they reach is around 10%. The idiosyncratic variance of the Materials sector peaks around 20%. For the Energy, Technology and Consumer Discretionary sectors, the maximum is around 30%. The Financial sector stands out with a maximum idiosyncratic variance that is close to the highest variance of the market factor, above 50%. This level is also close to the maximum level of idiosyncratic variance reached by the single stocks considered. Another striking pecularity of the Financials sector is that its idiosyncratic variance reaches a first peak end of 2008, simultaneously with the market variance, then goes down to 25% in early 2009, when the market variance goes down below 15%, but then it goes up again and reaches a peak that is similar to the first one around March 2009. This second peak is specific to the Financials sector. It occurs at a much smaller scale in the market variance, which goes up to 20%, and is insignificant in the variance trajectories of the other sectors. The only individual stocks 24 that witness this second peak are the stocks in the Financials sector as well as General Electric (GE) and UnitedHealth Group Inc. (UNH), which belong to the Industrials and Health Care sectors respectively. An explanation for the peculiar behaviour of GE is that it used to have a consumer lending division, and was therefore exposed to the risks specific to the financial industry. After the main market variance peak, the Energy and Materials sectors revert to an idiosyncratic variance level that is higher than the one of the market, as at the beginning of the times series. It is also the case for the Financials sector. Figure 7 illustrates the decomposition of the evolution of idiosyncratic variance into true idiosyncratic increments and market-induced increments. Two possible cases are observed. In both cases, the idiosyncratic movements control the evolution of the variance in low volatility periods. The difference occurs in high volatility times. In the first case, the idiosyncratic movements have the same magnitude as in calm times, then the variance peak comes from the impact of the market. This is the case of CAT (Caterpillar Inc.) for example, and for most stocks examined. In the second case, when the volatility peak does not replicate the one of the market, the true idiosyncratic variance remains in control of the total idiosyncratic variance. This is the case for GE (General Electric), and for companies in the financial industry such as JPMorgan Chase and Goldman Sachs. For these stocks, the volatility peak lasts longer than the one of the market, and therefore the idiosyncratic variance takes over the entire peak. 5.2 Relation to returns According to standard asset pricing theory, idiosyncratic volatility should not be priced in the crosssection of returns, as investors should be able to diversify this risk away. However, in the last decade many papers have found a relation between idiosyncratic volatility and expected returns.12 12 This phenomenon is sometimes referred to as the ”volatility anomaly”. There has been a debate on the sign of this relation. Ang, Hodrick, Xing, and Zhang (2006), Brockman and Yan (2008), Ang, Hodrick, Xing, and Zhang (2009), Jiang, Xu, and Yao (2009) and Guo and Savickas (2010) find an anomalous negative relation. In contrast, Malkiel and Xu (2001), Goyal and Santa-Clara (2003), Spiegel and Wang (2005), Fu (2009) and Garcia, Mantilla-Garcia, and Martellini (2011) find a positive relation. A number of studies also find that idiosyncratic volatility is not a priced risk factor, e.g., Fama and MacBeth (1973), Bali, Cakici, Yan, and Zhang (2005), Bali and Cakici (2008), Fink, Fink, and He (2012), Huang, Liu, Rhee, and Zhang (2010) and Han and Lesmond (2011). A few explanations have been proposed in the literature to explain the potential pricing of idiosyncratic risk in the cross-section of returns. During market turmoil, the assumption of perfectly liquid markets that underlies classical asset pricing theories no longer holds. Furthermore, agents may exhibit specific preferences with respect to the skewness and kurtosis of the returns’ distribution. Langlois (2013) argues that such preferences may incentivise investors to remain underdiversified, leading to a non zero price of idiosyncratic risk. Berrada and Hugonnier (2013) suggest that idiosyncratic volatility is generated by aggregated forecast error, in an incomplete information setting. 25 My model permits to analyze the relationship between idiosyncratic volatility and returns. To illustrate how the knowledge of the idiosyncratic volatility can help a portfolio manager selecting the assets that are relevant to a specific investor, I examine the performance of four weekly-rebalanced portfolios. Every week, I sort the values of idiosyncratic variances. Each portfolio contains a quarter of the stocks. Portfolio 1 contains the seven stocks which have the smallest idiosyncratic variance level, portfolio 4 contains those that have the largest variance levels. Stocks are given equal weights. Figure 8 illustrates the evolution of the wealth for the four portfolios. I assume an initial level of wealth of 100. Table 11 reports the main statistics of the portfolios. An investor who buys a portfolio of stocks with a higher idiosyncratic variance tends to receive higher returns, and a larger Sharpe ratio. The results remain unchanged if one sorts portfolios according to the idiosyncratic variance rate (which also includes the idiosyncratic jumps in returns), the ratio of idiosyncratic variance over total variance or the level of true idiosyncratic variance. They are also robust to a different weighting mechanism, where the position in each stock is proportional to the level of its variance. 6 Pricing of idiosyncratic risks The results of the last section suggest that idiosyncratic variance may contain useful information on future returns. This section examines whether idiosyncratic risk is priced in the cross-section of assets, by evaluating the contribution of idiosyncratic equity and variance risks to the equity and variance risk premia. The risk premia are calculated following equations (8) and (9). They are available in closed-form at every time t conditionally on the values of the latent variance factors. These values are estimated following the procedure outlined in section ??. 6.1 Equity Risk Premium The typical behaviour of the Integrated Equity Risk Premium (IERP) is illustrated in Figure 9, which represents the case of DD (DuPont). It is positive for all stocks and of smaller magnitude than the risk premium of the market. Its term structure is similar to the one of the index, i.e., its magnitude increases when the term increases during market calm, indicating that investors require a larger compensation when they invest on a longer-term horizon. In contrast, during market turmoil, the IERP becomes larger for smaller terms, as investors are unsure how markets will behave in the 26 near future and require compensation for that. The decomposition into an idiosyncratic and market component for a short-term horizon investment varies from stock to stock. For some stocks such as Boeing, idiosyncratic risk is not priced in the IERP, which suggests that investors think this risk can be diversified away. For other stocks like DuPont, the idiosyncratic component of the IERP constitutes an important part of the total IERP. However, for investments with longer time horizons, results are consistent across stocks and indicate that idiosyncratic risk is no longer priced. Figure 11 represents the one-month IERPs of sectors and compares them to the IERP of the Dow Jones components which belong to them. The sector IERP is smaller than the single stocks’ IERPs for all sectors but Energy and Financials. Furthermore, these two sectors are characterized by a large IERP even in times of market calm (around 5% in 2006). The computation of the ratio of idiosyncratic IERP over total IERP shows that the idiosyncratic IERP is responsible for a large part of the total premium for the Energy and Financials sectors: 86% and 83% respectively. It is also responsible for a substantial part of the Consumer Discretionary (XLY), Industrials (XLI) amd Health Care (XLV) sectors: 62%, 38% and 23% respectively. Looking one level below and separating the jump and diffusion contributions to the idiosyncratic IERP reveals that jumps only play a non negligible role for the Energy and Financials sectors, where they represent 31% and 51% of the total idiosyncratic component for the IERP. Investing in ETFs for all sectors except Energy and Financials is therefore a way for investors to be exposed to less diversifiable risk than what they would otherwise have to bear if investing in single stocks. Speculators who, in turn, would like to be exposed to idiosyncratic risk, and particularly to tail risk, can invest in the Energy or Financials ETFs, whose idiosyncratic IERP is larger than most of their components. These results should be put in perspective with those of Kelly and Lustig (2011) who show that government guarantees removed part of the tail risk of the financial sector. They show that there is still substantial tail risk that remains priced. 6.2 Variance Risk Premium A typical example of the Integrated Variance Risk Premium (IVRP) is represented in Figure 10. It tends to be negative, which means that investors are willing to pay to get protection against the variance fluctuations in most stocks. The amplitude of the IVRP varies very much from stock to stock. The pattern is similar across stocks, i.e., the IVRP is small in absolute value in times of 27 market calm, and peaks downward during market turmoil. The term structure is similar to the one of the market factor, i.e., the VRP becomes more negative when the term increases. This indicates that investors are willing to pay larger amounts to be covered against fluctuations in stock volatility, when they invest for longer terms. Such term structure can be benefited from in a trading strategy, as detailed in Filipovi´c, Gourier, and Mancini (2013). Note that my results do not contradict those of Driessen, Maenhout, and Vilkov (2009) who find no evidence of a negative risk premium on individual variance risk. Indeed, they are considering relatively short terms, from 14 to 60 days, and have option data from 1996 until 2003, i.e., prior to the volatility peak. In contrast to the IERP, a substantial part of the IVRP consists of its idiosyncratic component, for both short and long terms, as shown on the lower panels of Figure 10. Figure 12 represents the six-month IVRPs of sectors and compares them to the IERP of the Dow Jones components which belong to them. The six-month term is chosen as the magnitude of the IVRP increases with the term. Results are qualitatively similar for the one-month term. This analysis confirms that the Energy and Financials sectors are particularly risky sectors, because their variance risk premia are strongly negative. The part that corresponds to idiosyncratic risk is very high: 90 and 91% respectively. The jump component does not play a significant role in the variance risk premia. It accounts for 7% and 5% of the total variance risk premia of the Energy and Financials sectors. Two other sectors exhibit significant priced variance risk, namely the Materials and the Consumer Discretionary Sectors. 84% and 89% of their variance risk premia is idiosyncratic. If I go one level further and decompose the continuous part of the idiosyncratic variance risk premia into a component that is due to the common idiosyncratic variance, controlled by βvj , and another due to the true idiosyncratic variance, I obtain the results displayed on Figure 13. Interestingly, the common idiosyncratic variance carries a risk premium that tends to be close to zero in times of market calm, and significantly positive during market turmoil. This result is in line with the results of Sch¨ urhoff and Ziegler (2011). However, I find that a large part of the continuous idiosyncratic IVRP is driven by the true idiosyncratic variance: between 60% and 97% for the four sectors mentioned above. This justifies the resulting negative risk premia that I obtain. 28 7 Conclusion This paper revisit the question: does idiosyncratic risk matter? It introduces a flexible parametric framework for the study of the risks embedded in individual stocks. Using a particle filtering algorithm, I estimate the trajectory of idiosyncratic variance, based on the information contents of option prices and returns at different frequencies. I investigate the decomposition of the idiosyncratic variance movements into common idiosyncratic and true idiosyncratic changes. I show that idiosyncratic variance is dependent on the size and industry of the stock, and that it is a priced factor of risk. A thorough analysis of the equity and variance risk premia of individual stocks uncovers a substantial idiosyncratic component, in contrast to what standard asset pricing models predict. Therefore idiosyncratic risk matters, and must be taken into consideration by investors when forming their portfolios. Finally, I compare the risk present in individual stocks to the risk that is in the sectors they belong to. This analysis is based on the information contained in sector ETFs and derivatives on them. I show that most sector ETFs provide an interesting investment alternative for agents who are not willing to be exposed to non diversifiable equity risk, as their idiosyncratic risk premia are close to zero. Two notable exceptions are the Energy and Financials sectors, which provide significant exposure to idiosyncratic equity risks, and include substantial tail risk. 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The measures considered are the Realized Variance (RV), the Bipower Variation (BV) and the Continuous Variation (CV) on the left panel, and the Jump Variation on the right panel. They are computed based on 5-minute tick data. 1 1 0.95 0.8 0.9 0.85 0.6 0.8 0.4 0.75 RV BV CV 0.7 0.65 0 50 100 Lag (days) 0.2 0 0 150 50 100 Lag (days) 150 7 14 6 12 5 10 beta HML beta SMB Figure 2: Histograms of the betas associated with the SMB and HML factors in the Fama-French three-factor model. 4 3 8 6 2 4 1 2 0 −8 −6 −4 −2 0 2 0 −0.01 4 −3 x 10 34 0 0.01 0.02 0.03 Figure 3: Left panel: Evolution of the two-month at-the-money (ATM) level of the implied volatility (IV) of single stock options from January 4, 2006 until December 26, 2012. The ATM IV has been interpolated on the basis of available market data, using the biharmonic spline interpolation method of T.Sandwell (1987). Right panel: Median level of interpolated two-month ATM IV from March 3, j 2 2006 until December 26, 2012, versus the point estimate of the parameter (βdif f ) , which measures the impact of diffusive market movements on the returns of stock j. 1.4 JNJ IBM GS 1.5 GS AXP 1 j 2 (βdif f) 2−month ATM IV 1.2 0.8 0.6 1 CAT GE DIS DD BA JPM MSFT NKE HD 0.5 0.4 0.2 JNJ Jan−08 Jan−10 0 0.1 Jan−12 TRV CVX UTX XOM MRK MMM PFE WMT MCD IBM VZ T KO 0 INTC PG 0.15 0.2 0.25 0.3 median of 2-month ATM IV 0.35 Figure 4: Difference between the 95% and the 5% quantile of interpolated two-month ATM IV from j March 3, 2006 until December 26, 2012, versus the point estimate of the parameter βdif f (left panel) j j 3 resp. (βdif f ) (right panel). βdif f measures the impact of diffusive market movements on the returns of stock j. 1.4 2 GS 1.2 GS 1.5 AXP CAT GE DIS BADD 0.8 0.6 JPM MSFT NKE HD INTC AXP j 3 (βdif f) j βdif f 1 1 CAT GE DIS BADD TRV 0.5 T CVX UTX KOXOM PFE MMM MRK WMT MCD IBM VZ PG JNJ JPM MSFT NKE HD INTC T CVX UTX KOXOM PFE MMM MRK WMT MCD IBM VZ PG JNJ 0.4 0.1 0.2 0.3 0.4 0.5 0.6 0.7 95% minus 5% quantile of 2-month ATM IV TRV 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 95% minus 5% quantile of 2-month ATM IV 35 Figure 5: Decomposition of the evolution of the diffusive and jump components of the variance rate (Total var. rate) of INTC (βdif f = 0.75, βjump = 1.35) into an idiosyncratic component (Idio. part) and a component that results from the impact of the market factor (Market part). 0.12 Total var. rate Idio. part Market part 0.6 0.4 0.2 Total var. rate Idio. part Market part 0.1 Jump variance rate Diffusive variance rate 0.8 0.08 0.06 0.04 0.02 0 0 Jan−08 Jan−10 Jan−12 Jan−08 36 Jan−10 Jan−12 Figure 6: Total idiosyncratic variance of every sector versus the variance of its components that are part of the Dow Jones. The sector ”Utilities” has not been represented as no constituent of the Dow Jones is part of it. Energy Technology 0.7 0.7 Market XLE XOM CVX 0.6 0.5 0.5 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 0 2007 2008 2009 2010 2011 Market XLK MSFT VZ IBM T INTC CSCO 0.6 0 2012 2007 2008 Materials 2012 0.5 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 2007 2008 2009 2010 2011 Market XLP PG KO WMT 0.6 0.5 0 2012 2007 2008 ConsumerDiscretionary 2009 2010 2011 2012 Industrials 0.7 0.7 Market XLY DIS HD MCD NKE 0.6 0.5 0.5 0.4 0.3 0.3 0.2 0.2 0.1 0.1 2007 2008 2009 2010 2011 Market XLI GE UTX MMM BA CAT 0.6 0.4 0 2012 2007 2008 HealthCare 2009 2010 2011 2012 Financials 0.7 0.7 Market XLV JNJ PFE MRK UNH 0.6 0.5 0.5 0.4 0.3 0.3 0.2 0.2 0.1 0.1 2007 2008 2009 2010 2011 2012 Market XLF JPM AXP GS TRV 0.6 0.4 0 2011 0.7 Market XLB DD 0.6 0 2010 ConsumerStaples 0.7 0 2009 37 0 2007 2008 2009 2010 2011 2012 Figure 7: Decomposition of the evolution of the idiosyncratic variance of two stocks (CAT on the left and GE on the right) into true idiosyncratic movements and common movements. Total id. var True id. var Market var 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 0 Jan−08 Jan−10 Total id. var True id. var Market var 0.5 vˆt vˆt 0.5 0 Jan−12 Jan−08 Jan−10 Jan−12 Figure 8: Evolution of the wealth process of four portfolios that are weekly rebalanced depending on the level of idiosyncratic variance (Panel A) and of true idiosyncratic variance (Panel B) of each stock. Portfolio 1 contains every week a combination of the 7 stocks with the smallest idiosyncratic variance. Portfolio 4 contains the 7 stocks with the largest idiosyncratic variance. Stocks are equally weighted. The initial wealth level is 100. Panel A Panel B 200 1(smallest) 2 3 4 (largest) 1(smallest) 2 3 4 (largest) Wealth 150 Wealth 150 200 100 50 100 Jan−08 Jan−10 50 Jan−12 38 Jan−08 Jan−10 Jan−12 Figure 9: Left panel: Term structure of the IERP for DD (DuPont), from March 3, 2006 until December 26, 2012. Right panel: Evolution of the instantaneous IERP and decomposition into idiosyncratic and systematic movements from March 3, 2006 until December 26, 2012, for DD (DuPont). 0.2 ∆t 1m 3m 6m IERP(t,T) IERP(t,T) 0.15 Total Idiosyncratic 0.4 0.1 0.05 0.3 0.2 0.1 0 0 Jan−08 Jan−10 Jan−12 Jan−08 Jan−10 Jan−12 Figure 10: Upper panel: Term structure of the IVRP for DD (DuPont), from March 3, 2006 until December 26, 2012. lower panels: Dcomposition of the instantaneous and 6-month IVRP into idiosyncratic and systematic movements. ∆t 1m 3m 6m 0.04 IVRP(t,T) 0.02 0 −0.02 −0.04 −0.06 Jan−08 −3 5 x 10 Jan−10 Instantaneous IVRP Jan−12 6−month IVRP 0.01 0 0 −0.01 −5 −0.02 −10 −0.03 −0.04 −15 Total Idiosyncratic −20 Jan−08 Jan−10 Total Idiosyncratic −0.05 −0.06 Jan−12 39 Jan−08 Jan−10 Jan−12 Figure 11: One-month total IERP of every sector versus the IERP of its components that are part of the Dow Jones. The sector ”Utilities” has not been represented as no constituent of the Dow Jones is part of it. Energy Technology 0.45 0.45 XLE XOM CVX 0.4 XLK MSFT VZ IBM T INTC CSCO 0.4 0.35 0.35 0.3 0.3 0.25 0.25 0.2 0.2 0.15 0.15 0.1 0.1 0.05 0.05 0 0 2007 2008 2009 2010 2011 2012 2007 2008 Materials 2009 2010 2011 2012 ConsumerStaples 0.45 0.45 XLB DD 0.4 XLP PG KO WMT 0.4 0.35 0.35 0.3 0.3 0.25 0.25 0.2 0.2 0.15 0.15 0.1 0.1 0.05 0.05 0 0 2007 2008 2009 2010 2011 2012 2007 2008 ConsumerDiscretionary 2009 2010 2011 2012 Industrials 0.45 0.45 XLY DIS HD MCD NKE 0.4 0.35 XLI GE UTX MMM BA CAT 0.4 0.35 0.3 0.3 0.25 0.25 0.2 0.2 0.15 0.15 0.1 0.1 0.05 0.05 0 0 2007 2008 2009 2010 2011 2012 2007 2008 HealthCare 2009 2010 2011 2012 Financials 0.45 0.45 XLV JNJ PFE MRK UNH 0.4 0.35 0.35 0.3 0.3 0.25 0.25 0.2 0.2 0.15 0.15 0.1 0.1 0.05 0.05 0 2007 2008 2009 2010 2011 2012 XLF JPM AXP GS TRV 0.4 40 0 2007 2008 2009 2010 2011 2012 Figure 12: Six-month total IVRP of every sector versus the IVRP of its components that are part of the Dow Jones. The sector ”Utilities” has not been represented as no constituent of the Dow Jones is part of it. Energy Technology −0.02 −0.02 −0.04 −0.04 −0.06 −0.06 −0.08 −0.08 −0.1 −0.1 −0.12 −0.12 −0.14 −0.14 −0.16 −0.16 XLE XOM CVX −0.18 −0.2 XLK MSFT VZ IBM T INTC CSCO −0.18 −0.2 −0.22 −0.22 2007 2008 2009 2010 2011 2012 2007 2008 Materials 2009 2010 2011 ConsumerStaples −0.02 −0.02 −0.04 −0.04 −0.06 −0.06 −0.08 −0.08 −0.1 −0.1 −0.12 −0.12 −0.14 −0.14 −0.16 −0.16 −0.18 XLP PG KO WMT −0.18 −0.2 −0.2 XLB DD −0.22 2007 2008 2009 2010 2011 −0.22 2012 2007 2008 ConsumerDiscretionary 2009 2010 2011 −0.02 −0.04 −0.04 −0.06 −0.06 −0.08 −0.08 −0.1 −0.1 −0.12 −0.12 −0.14 −0.14 −0.16 XLI GE UTX MMM BA CAT −0.16 XLY DIS HD MCD NKE −0.18 −0.2 −0.22 2008 2009 2010 2011 2012 Industrials −0.02 2007 2012 −0.18 −0.2 −0.22 2012 2007 2008 HealthCare 2009 2010 2011 2012 Financials −0.02 −0.02 −0.04 −0.04 −0.06 −0.06 −0.08 −0.08 −0.1 −0.1 −0.12 −0.12 −0.14 −0.14 −0.16 −0.16 XLV JNJ PFE MRK UNH −0.18 −0.2 −0.22 2007 2008 2009 2010 2011 2012 XLF JPM AXP GS TRV −0.18 −0.2 41 −0.22 2007 2008 2009 2010 2011 2012 Figure 13: Six-month idiosyncratic common IVRP of every sector versus the IVRP of its components that are part of the Dow Jones. The sector ”Utilities” has not been represented as no constituent of the Dow Jones is part of it. Energy Technology 0.05 0.05 XLE XOM CVX 0.04 0.03 0.03 0.02 0.02 0.01 0.01 0 0 −0.01 −0.01 −0.02 2007 2008 2009 2010 2011 XLK MSFT VZ IBM T INTC CSCO 0.04 −0.02 2012 2007 2008 Materials 2009 2010 2011 2012 ConsumerStaples 0.05 0.05 XLP PG KO WMT XLB DD 0.04 0.04 0.03 0.03 0.02 0.02 0.01 0.01 0 0 −0.01 −0.01 −0.02 2007 2008 2009 2010 2011 −0.02 2012 2007 2008 ConsumerDiscretionary 2011 2012 0.05 XLY DIS HD MCD NKE 0.04 0.03 0.02 0.02 0.01 0.01 0 0 −0.01 −0.01 2007 2008 2009 2010 2011 XLI GE UTX MMM BA CAT 0.04 0.03 −0.02 2012 2007 2008 HealthCare 2009 2010 2011 2012 Financials 0.05 0.05 XLV JNJ PFE MRK UNH 0.04 0.03 0.02 0.02 0.01 0.01 0 0 −0.01 −0.01 2007 2008 2009 2010 2011 2012 XLF JPM AXP GS TRV 0.04 0.03 −0.02 2010 Industrials 0.05 −0.02 2009 42 −0.02 2007 2008 2009 2010 2011 2012 Table 1: This table reports the results of the Functional Principal Analysis (FPCA) of the IV surfaces of single stocks. The stocks considered are the constituents of the Dow Jones. The second column describes what the top three eigenmodes (EM) of the decomposition represent. The next three columns provide the percentage of variance explained by each of them. The last three columns give the correlation between each principal component (PC) process the stocks’ FPCA and the corresponding principal component process of the S&P 500 FPCA. All numbers are in percentages. Top 3 eigenmodes AXP BA CAT CVX DD DIS GE GS JPM KO T XOM HD INTC IBM JNJ MCD MRK MSFT MMM NKE PFE PG TRV UTX VZ WMT level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, level, skewness, TS TS, skewness skewness, convexity skewness, TS skewness, TS skewness, TS TS, skewness skewness, TS TS, skewness skewness, TS skewness, TS skewness, TS skewness, TS skewness, TS skewness, TS skewness, TS skewness, TS skewness, TS TS, skewness skewness, TS TS, skewness skewness, TS skewness, TS TS, skewness skewness, TS TS, skewness skewness, TS Var. explained by EM 1st EM 2nd EM 3rd EM 99.6 98.8 91.8 96.8 98.8 98.7 99.7 99.1 99.6 98.8 94.8 86.8 98.6 97.6 98 97.7 96 98.1 98.9 97.7 98.5 98.7 97.7 99.6 98.4 97.2 97.5 0.2 0.6 6.3 2.5 0.7 0.6 0.2 0.5 0.2 0.7 3.54 9.4 0.9 1.5 1.1 1.6 2.7 1 0.7 1.4 0.7 0.6 1.4 0.2 0.9 1.9 1.7 43 0.2 0.5 1.0 0.4 0.5 0.5 0.1 0.3 0.1 0.4 1.1 2.3 0.4 0.6 0.7 0.5 0.8 0.6 0.3 0.6 0.6 0.5 0.7 0.1 0.5 0.6 0.5 Correl. with PC of S&P 500 IV FPCA 1st PC 2nd PC 3rd PC 91.6 95.4 92.0 94.5 97.3 96.7 89.6 88.2 91.4 95.3 87.0 85.1 88.6 88.0 94.0 95.4 81.2 87.7 94.1 97.1 95.4 93.8 94.7 90.2 97.8 85.7 85.3 49.8 65.6 24.7 72.0 60.9 44.9 46.1 34.2 37.1 53.7 57.8 45.2 55.6 56.0 59.7 52.2 55.1 60.8 48.3 63.3 55.0 44.8 51.0 47.8 63.2 29.6 58.5 40.3 43.6 5.1 56.5 43.7 32.9 32.3 33.8 40.5 57.8 52.9 24.2 47.8 33.6 39.7 42.5 26.4 44.7 59.1 46.2 57.0 54.3 51.5 41.2 53.0 47.7 48.4 44 13770 2827 4913 2124 2342 1564 4078 5233 4459 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m IBM 11583 1885 3942 1993 2114 1649 3095 4965 3523 9335 1107 3337 1624 1854 1413 2649 3731 2955 10564 1405 4160 2158 1959 882 3731 4213 2620 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m BA 9702 760 3873 1668 1840 1561 2639 4259 2804 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m 7969 531 2810 1480 1563 1585 2493 3197 2279 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m AXP 7054 1448 3061 1441 817 287 2056 2848 2150 3742 260 1566 966 642 308 1018 1406 1318 JNJ 10178 2004 4075 2018 1443 638 2767 4350 3061 7858 695 3187 1663 1625 688 2025 3417 2416 10302 1647 4007 2214 1942 492 3383 4312 2607 7089 609 2685 1429 1360 1006 2055 2890 2144 DD DIS 5357 360 1931 1078 1187 801 1500 2222 1635 7899 456 2412 1368 1614 2049 2204 3452 2243 GE 6129 621 2159 1123 1242 984 1660 2404 2065 13156 1710 4593 2225 2892 1736 3230 6050 3876 8554 1556 3036 1697 1533 732 2511 3335 2708 9765 1619 3728 1719 1482 1217 2765 3926 3074 Out-of-sample period 5889 361 2153 1168 1284 923 1596 2242 2051 In-sample period 7870 705 2501 1359 1682 1623 2522 3086 2262 9790 1426 3848 1739 1886 891 2135 4558 3097 5605 451 1824 986 1134 1210 1333 2422 1850 PFE 10518 1542 3644 1602 2034 1703 2281 4866 3371 NKE 11213 1712 4420 2166 2079 836 3696 4683 2834 MMM 11033 1721 4709 2105 1692 806 3592 4612 2829 Out-of-sample period 6411 347 2345 1447 1495 777 1980 2634 1797 In-sample period MSFT 8739 1182 3314 1343 1563 1337 2247 3902 2590 6337 657 2249 1035 1151 1245 1970 2410 1957 CSCO MRK 10745 2141 4233 1540 1593 1238 2726 4545 3474 8070 730 2801 1409 1731 1399 1963 3389 2718 CVX MCD 13499 2147 4494 1892 2286 2680 3606 5712 4181 12038 1044 4311 2008 2160 2519 3556 5360 3122 CAT 7501 1746 3187 1508 860 200 2211 3063 2227 5772 450 2411 1405 1049 457 1707 2244 1821 PG 14722 2099 4327 1808 2560 3928 4288 5633 4801 16351 1958 5491 2228 2705 3969 4903 6182 5266 GS 3726 553 1562 823 588 200 944 1482 1300 3991 369 1386 713 811 712 1011 1593 1387 TRV 19939 2575 6596 3437 4262 3069 4881 9053 6005 10606 956 3783 1865 1954 2048 2949 4615 3042 JPM 11307 1478 4509 2127 2109 1084 3517 4956 2834 8184 648 2663 1336 1605 1932 2072 3601 2511 UNH 8625 2028 3552 1767 1041 237 2239 3758 2628 6129 322 2443 1667 1156 541 1571 2636 1922 KO 10129 1963 3575 1784 1850 957 2570 4511 3048 6274 584 2215 1138 1304 1033 1474 2693 2107 UTX 9262 1381 3995 1787 1737 362 2406 4272 2584 7009 622 2437 1331 1601 1018 2287 2760 1962 T VZ 13925 2422 5776 2691 2493 543 3652 6541 3732 6500 600 2293 1280 1466 861 1922 2552 2026 10121 2237 3824 1691 1515 854 2895 3943 3283 8655 829 3059 1432 1633 1702 2469 3378 2808 XOM 8194 1903 3425 1543 980 343 2171 3590 2433 8544 638 3194 1762 1925 1028 2291 3596 2657 WMT 11834 1940 4687 2163 2164 880 3423 5374 3037 7843 639 2531 1282 1646 1745 1997 3429 2417 HD 11458 1370 4061 1816 2501 1710 2814 5307 3337 6550 570 2003 973 1305 1699 2002 2585 1963 INTC Table 2: This table reports the number of options included in the in-sample (e.g., estimation period) and out-of-sample exercises for each stock in the Dow Jones. The in-sample period starts in March 2006, until the end of 2009. The out-of-sample period ranges from the beginning of 2010 until the end of 2012. 45 0.264 0.245 0.267 0.301 0.255 0.193 0.097 0.232 0.426 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m BA 0.500 0.516 0.593 0.529 0.416 0.258 0.251 0.427 0.710 0.520 0.379 0.542 0.690 0.526 0.377 0.214 0.439 0.753 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m CAT 0.199 0.136 0.202 0.251 0.210 0.072 0.085 0.172 0.290 0.215 0.245 0.240 0.219 0.174 0.078 0.125 0.193 0.283 CVX 0.230 0.131 0.232 0.295 0.251 0.169 0.092 0.186 0.345 0.375 0.369 0.403 0.410 0.341 0.183 0.138 0.299 0.560 0.168 0.129 0.196 0.187 0.124 0.071 0.061 0.147 0.266 0.204 0.187 0.232 0.220 0.179 0.125 0.104 0.200 0.270 DD DIS 0.179 0.239 0.216 0.188 0.170 0.100 0.113 0.162 0.246 GE 0.092 0.078 0.096 0.115 0.091 0.056 0.042 0.064 0.145 0.385 0.310 0.486 0.417 0.255 0.100 0.131 0.310 0.578 0.302 0.278 0.324 0.375 0.267 0.148 0.172 0.269 0.412 0.077 0.061 0.085 0.089 0.073 0.035 0.034 0.049 0.120 0.074 0.078 0.087 0.093 0.060 0.031 0.044 0.056 0.104 In-sample period 0.350 0.265 0.398 0.318 0.340 0.236 0.397 0.279 0.400 0.315 0.173 0.190 0.161 0.127 0.308 0.220 0.478 0.372 Out-of-sample period 0.168 0.129 0.188 0.201 0.172 0.105 0.083 0.161 0.236 PG 0.196 0.089 0.184 0.279 0.229 0.117 0.080 0.162 0.294 KO TRV 0.301 0.224 0.311 0.352 0.294 0.169 0.095 0.244 0.431 T UNH 0.215 0.197 0.192 0.246 0.256 0.173 0.099 0.182 0.338 UTX 0.330 0.304 0.375 0.391 0.261 0.144 0.121 0.313 0.451 HD VZ 0.149 0.108 0.181 0.155 0.103 0.065 0.053 0.105 0.248 0.080 0.069 0.073 0.100 0.088 0.065 0.040 0.051 0.128 0.089 0.080 0.085 0.112 0.110 0.059 0.047 0.088 0.118 INTC 0.150 0.090 0.140 0.226 0.142 0.083 0.085 0.135 0.205 0.332 0.344 0.305 0.392 0.365 0.197 0.132 0.257 0.499 WMT 0.150 0.163 0.160 0.163 0.124 0.077 0.062 0.133 0.229 0.189 0.251 0.217 0.201 0.171 0.106 0.078 0.162 0.271 0.211 0.212 0.190 0.240 0.248 0.135 0.105 0.174 0.306 0.791 0.520 1.167 0.478 0.287 0.134 0.432 1.014 0.730 0.485 0.482 0.555 0.530 0.482 0.269 0.221 0.410 0.693 XOM 0.288 0.278 0.230 0.374 0.365 0.160 0.141 0.239 0.401 0.137 0.097 0.162 0.147 0.096 0.059 0.041 0.085 0.232 0.213 0.169 0.219 0.255 0.226 0.124 0.084 0.180 0.330 0.281 0.257 0.289 0.289 0.240 0.304 0.128 0.271 0.373 0.233 0.113 0.197 0.344 0.290 0.162 0.089 0.189 0.346 0.209 0.214 0.224 0.201 0.207 0.150 0.096 0.194 0.282 1.042 0.834 0.989 1.047 1.211 1.026 0.442 0.857 1.462 0.224 0.229 0.221 0.283 0.234 0.109 0.090 0.179 0.335 0.430 0.453 0.349 0.488 0.542 0.375 0.223 0.352 0.639 JPM 0.331 0.264 0.277 0.389 0.419 0.216 0.151 0.306 0.460 0.710 0.611 0.809 1.006 0.732 0.388 0.336 0.577 1.026 PFE 0.095 0.107 0.119 0.099 0.063 0.035 0.042 0.065 0.144 GS 1.418 1.463 1.639 1.616 1.361 0.888 0.816 1.308 1.902 NKE 0.125 0.096 0.120 0.169 0.100 0.124 0.064 0.120 0.180 MMM 0.251 0.213 0.265 0.289 0.239 0.138 0.082 0.213 0.404 Out-of-sample period 0.128 0.062 0.077 0.169 0.180 0.088 0.077 0.116 0.175 In-sample period 0.213 0.267 0.221 0.227 0.198 0.157 0.075 0.186 0.325 MSFT 0.100 0.049 0.097 0.147 0.114 0.059 0.058 0.078 0.148 0.110 0.083 0.099 0.129 0.134 0.102 0.063 0.096 0.155 CSCO MRK 0.483 0.411 0.602 0.523 0.315 0.170 0.184 0.455 0.653 0.599 0.543 0.615 0.660 0.650 0.442 0.322 0.530 0.799 MCD 0.476 0.403 0.540 0.577 0.476 0.310 0.148 0.440 0.671 0.305 0.338 0.327 0.359 0.309 0.175 0.148 0.295 0.429 JNJ 0.274 0.274 0.282 0.319 0.281 0.167 0.122 0.230 0.400 0.243 0.255 0.201 0.293 0.311 0.173 0.146 0.228 0.325 IBM 0.386 0.418 0.353 0.387 0.429 0.384 0.198 0.352 0.550 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m AXP Table 3: This table reports the root mean-square errors (RMSEs) which result from the estimation for each stock’s options, in the inand out-of-sample periods. The in-sample period starts in March 2006, until the end of 2009. The out-of-sample period ranges from the beginning of 2010 until the end of 2012. Table 4: This table reports the point estimates of the parameters which govern single stock returns’ dynamics. Below each estimate, the corresponding standard error is given in parentheses. The estimation period starts in March 2006, until the end of 2009. AXP BA CAT CVX DD DIS GE GS JPM KO T XOM HD INTC IBM JNJ MCD MRK MSFT MMM NKE PFE PG TRV UTX VZ WMT CSCO UNH κjP v θ jP y jP µjP σ jP κjv θj yj µj σj λ0 j λ1 j j σv ρj ηj 5.900 1.491 7.000 1.666 3.700 2.280 7.700 1.840 5.700 1.214 6.100 1.460 8.500 2.837 8.166 1.922 4.600 1.572 7.389 1.696 6.300 1.194 6.360 1.243 5.474 1.129 6.500 1.825 4.700 0.000 8.200 2.341 6.700 0.964 6.686 1.163 6.100 1.351 8.200 1.679 7.029 5.285 6.680 4.934 9.000 2.757 5.700 0.900 5.200 1.481 5.700 1.267 5.700 1.540 7.600 1.858 4.700 1.912 0.001 0.040 0.067 0.030 0.078 0.070 0.042 0.050 0.060 0.150 0.060 0.040 0.066 0.030 0.065 0.061 0.024 0.110 0.063 0.027 0.013 0.090 0.047 0.074 0.027 0.067 0.028 0.100 0.033 0.150 0.000 0.110 0.048 0.070 0.032 0.037 0.054 0.070 0.043 0.050 0.021 0.052 2.979 0.030 2.978 0.100 0.030 0.100 0.015 0.100 0.045 0.100 0.049 0.100 0.040 0.130 0.035 0.140 0.039 -0.030 0.028 0.010 0.040 -0.030 0.026 -0.050 0.048 -0.030 0.011 0.000 0.076 -0.010 0.038 -0.040 0.013 -0.010 0.021 -0.030 0.040 0.001 0.049 0.000 0.037 0.000 0.016 -0.060 0.058 -0.010 0.000 -0.010 0.028 -0.010 0.024 -0.030 0.028 0.010 0.042 0.030 0.052 -0.060 0.049 0.000 0.028 -0.100 0.102 -0.040 0.036 -0.020 0.043 -0.020 0.037 -0.020 0.034 -0.010 0.037 0.010 0.051 0.050 0.103 0.050 0.028 0.050 0.028 0.050 0.030 0.050 0.014 0.014 0.039 0.100 0.030 0.100 0.012 0.020 0.054 0.150 0.054 0.011 0.065 0.111 0.042 0.013 0.083 0.150 0.073 0.020 0.000 0.050 0.026 0.080 0.027 0.122 0.064 0.050 0.026 0.160 0.031 0.111 2.214 0.120 2.208 0.160 0.011 0.130 0.027 0.150 0.040 0.190 0.037 0.190 0.128 0.050 0.025 0.110 0.046 2.900 1.183 2.900 1.390 4.500 1.328 2.500 1.543 5.500 1.630 1.200 1.561 3.500 1.186 2.460 1.504 2.400 1.314 1.649 1.124 2.600 1.626 2.460 1.939 2.460 1.410 2.400 0.840 2.300 0.000 2.300 1.211 4.500 1.622 1.649 2.097 3.500 1.147 1.900 0.456 2.117 1.446 1.640 0.995 3.300 0.595 3.700 0.128 3.200 0.997 3.200 0.792 3.600 1.170 4.900 1.999 2.400 1.428 0.002 0.016 0.020 0.027 0.023 0.024 0.011 0.023 0.002 0.014 0.008 0.030 0.003 0.016 0.007 0.022 0.002 0.016 0.005 0.011 0.006 0.014 0.007 0.017 0.004 0.022 0.029 0.028 0.003 0.000 0.000 0.013 0.017 0.016 0.006 0.027 0.014 0.016 0.002 0.022 0.006 5.059 0.005 5.072 0.011 0.010 0.027 0.017 0.017 0.017 0.017 0.012 0.010 0.022 0.020 0.032 0.030 0.021 0.080 0.042 0.120 0.064 0.040 0.052 0.040 0.033 0.060 0.018 0.060 0.028 0.020 0.029 0.067 0.010 0.040 0.026 0.030 0.015 0.040 0.028 0.033 0.034 0.055 0.019 0.060 0.029 0.100 0.000 0.020 0.038 0.040 0.055 0.033 0.045 0.020 0.047 0.080 0.037 0.041 3.132 0.070 3.172 0.040 0.040 0.060 0.030 0.040 0.053 0.040 0.036 0.040 0.038 0.060 0.024 0.020 0.053 -0.010 0.049 -0.020 0.048 -0.040 0.036 -0.020 0.039 -0.060 0.017 -0.040 0.058 -0.060 0.021 -0.080 0.013 -0.020 0.037 -0.070 0.042 -0.020 0.037 -0.090 0.033 -0.050 0.017 -0.030 0.051 -0.020 0.000 -0.080 0.043 -0.020 0.037 -0.070 0.031 -0.060 0.030 -0.050 0.027 -0.050 0.034 -0.090 0.036 -0.010 0.045 -0.060 0.040 0.010 0.044 0.010 0.028 0.020 0.081 -0.060 0.027 -0.100 0.054 0.110 0.063 0.090 0.060 0.050 0.102 0.170 0.037 0.130 0.048 0.090 0.058 0.160 0.051 0.111 0.017 0.090 0.058 0.091 0.053 0.110 0.063 0.122 0.040 0.060 0.023 0.190 0.060 0.170 0.000 0.090 0.036 0.070 0.100 0.122 0.055 0.070 0.087 0.130 0.026 0.165 2.138 0.135 2.119 0.150 0.049 0.130 0.030 0.070 0.106 0.070 0.122 0.070 0.081 0.150 0.056 0.130 0.036 0.080 0.042 0.120 0.064 0.040 0.052 0.040 0.033 0.060 0.018 0.060 0.028 0.020 0.029 0.067 0.010 0.040 0.026 0.030 0.015 0.040 0.028 0.033 0.034 0.055 0.019 0.060 0.029 0.100 0.000 0.020 0.038 0.040 0.055 0.033 0.045 0.020 0.047 0.080 0.037 0.041 3.132 0.070 3.172 0.040 0.040 0.060 0.030 0.040 0.053 0.040 0.036 0.040 0.038 0.060 0.024 0.020 0.053 4.700 2.194 6.300 1.804 5.500 1.767 5.100 2.427 6.700 1.721 5.900 1.677 7.600 1.806 4.482 1.876 9.500 2.840 7.389 1.877 9.300 3.443 6.050 1.749 9.400 2.650 4.900 2.407 7.500 0.000 5.500 2.473 6.500 1.682 9.974 4.369 8.100 2.204 4.400 2.371 5.474 3.499 9.770 7.787 7.900 2.112 6.600 0.782 6.500 2.131 6.500 1.631 6.500 1.955 3.700 2.530 4.600 3.698 0.300 0.113 0.300 0.103 0.200 0.091 0.200 0.115 0.250 0.055 0.450 0.186 0.500 0.194 0.333 0.057 0.300 0.075 0.202 0.105 0.330 0.061 0.273 0.070 0.273 0.070 0.300 0.118 0.300 0.000 0.350 0.127 0.400 0.131 0.223 0.106 0.200 0.108 0.300 0.061 0.273 1.812 0.310 1.824 0.400 0.118 0.300 0.105 0.350 0.106 0.350 0.100 0.350 0.121 0.250 0.100 0.250 0.078 -0.550 0.105 -0.600 0.062 -0.550 0.092 -0.600 0.050 -0.600 0.029 -0.450 0.126 -0.500 0.137 -0.589 0.020 -0.600 0.047 -0.589 0.116 -0.600 0.059 -0.666 0.062 -0.589 0.022 -0.550 0.096 -0.500 0.000 -0.650 0.097 -0.600 0.059 -0.589 0.041 -0.500 0.101 -0.550 0.039 -0.547 2.682 -0.590 2.732 -0.550 0.051 -0.550 0.049 -0.500 0.100 -0.500 0.124 -0.500 0.130 -0.550 0.052 -0.550 0.077 0.395 0.208 0.400 0.341 0.663 0.162 0.901 0.189 -0.050 0.159 0.750 0.348 0.750 0.255 0.095 0.152 0.200 0.213 0.658 0.164 0.390 0.176 0.650 0.168 0.850 0.133 0.350 0.243 -0.100 0.000 -0.050 0.117 0.850 0.154 -0.100 0.249 0.715 0.136 0.453 0.123 0.893 0.163 0.425 0.225 0.298 0.101 0.280 0.108 0.400 0.184 0.650 0.255 0.400 0.219 0.900 0.318 0.200 0.122 0.008 0.028 0.004 0.002 0.000 0.001 0.002 0.001 0.001 0.000 0.003 0.002 0.011 0.001 0.000 0.011 0.002 0.008 0.000 0.002 0.001 0.004 0.018 0.010 0.001 0.000 0.000 0.000 46 Table 5: This table reports the point estimates and standard errors (in italic) of the beta coefficients. The estimation period starts in March 2006, until the end of 2009. j Est. βdif f Std. err. j Est. βjump Std. err. j βv Est. Std. err. Consumer staples KO PG WMT 0.607 0.450 0.560 0.130 0.189 0.144 0.607 9.000 0.650 0.129 0.408 0.283 0.301 0.300 0.300 0.375 0.209 0.412 Pharmaceutical JNJ MRK UNH PFE 0.410 0.607 0.810 0.600 0.094 0.110 0.258 0.878 8.200 6.686 1.250 6.680 0.229 0.164 0.228 2.264 0.200 0.301 0.000 0.490 0.486 0.446 0.618 0.000 Energy CVX XOM 0.660 0.607 0.086 0.119 1.100 1.105 0.221 0.192 0.200 0.259 0.520 0.438 Technology IBM MSFT VZ T CSCO INTC 0.530 0.800 0.500 0.560 1.140 0.750 0.000 0.149 0.215 0.000 0.268 0.103 4.700 6.100 5.700 0.819 1.000 6.500 0.000 0.545 0.411 0.000 0.001 0.215 0.150 0.250 0.150 0.368 0.000 0.250 0.000 0.246 0.216 0.000 0.463 0.628 Industrials MMM UTX GE BA CAT 0.600 0.650 0.920 0.890 0.990 0.162 0.209 0.163 0.163 0.150 8.200 0.002 0.400 1.450 0.650 0.480 0.382 0.593 0.738 0.407 0.200 0.150 0.000 0.150 0.450 0.222 0.250 0.310 0.283 0.278 Materials DD 0.770 0.080 0.300 0.225 0.550 0.690 Consumer discretionary MCD HD NKE DIS 0.540 0.779 0.790 0.900 0.210 0.073 1.053 0.216 0.600 5.474 7.029 1.100 0.232 0.109 1.942 0.244 0.150 0.273 0.157 0.100 0.409 0.349 1.314 0.234 Financials AXP JPM TRV GS 1.120 0.840 0.720 1.221 0.384 0.219 0.160 0.199 0.550 0.950 0.900 0.497 0.301 0.228 0.000 0.107 0.050 0.250 0.600 0.273 0.171 0.439 0.113 0.404 Table 6: This table reports the results of a regression comparing synthesized VS rates following the procedure described in Carr and Wu (2009) with model-implied VS rates, following equation (10). The sampling frequency is weekly. The first column is based on repeated cross-sectional regressions (Fama-MacBeth). The reported coefficients are averages of the weekly coefficient estimates. Standard errors are calculated using the method of Newey-West with 8 lags. The standard errors of the intercept coefficients are multiplied by 100. The second column reports the results of a pooled panel regression. The last line reports the p-value when testing a hypothesis test with null H0 : the model perfectly represents VS rates, i.e., the intercept is zero and the slope is one. Cross-sectional Panel 0.98 (0.20) 0.88 (0.02) -0.27 (0.27) 0.96 (0.03) 0.82 357 0.82 0.70 9639 0.79 Intercept ×100 Slope R2 N H0 p-value [%] 47 Table 7: This table reports the results of a regression comparing ex ante synthesized VS rates at time t + τ , where VS rates are computed following the procedure described in Carr and Wu (2009), with model-implied predictions at time t, given by EP [VSt+τ ]. The model predictions are compared to predictions given by the martingale method, whose prediction of future VS rate is the current VS rate. Cross-sectional regressions (Fama-MacBeth) as well as pooled panel regressions are conducted, for three values of τ : one week (1w), one month (1m) and 6 weeks (5w). For cross-sectional regressions, the reported coefficients are averages of the weekly coefficient estimates. Standard errors are calculated using the method of Newey-West with 8 lags. The standard errors of the intercept coefficients are multiplied by 100. The last line reports the p-value when testing a hypothesis test with null H0 : the prediction perfectly matches future VS rates, i.e., the intercept is zero and the slope is one. τ = 1w Model Martingale Cr. sec. Panel Cr. sec. Panel Intercept ×100 Slope R2 N H0 p-value [%] τ = 1m Model Martingale Cr. sec. Panel Cr. sec. Panel τ = 6w Model Martingale Cr. sec. Panel Cr. sec. Panel 1.03 (0.21) 0.86 (0.02) 0.34 (0.32) 0.99 (0.05) 0.58 (0.16) 0.95 (0.01) 2.38 (1.27) 0.71 (0.15) 1.59 (0.30) 0.94 (0.06) -1.21 (0.57) 1.44 (0.10) 1.27 (0.28) 0.87 (0.03) 3.06 (1.19) 0.63 (0.14) 2.04 (0.39) 0.99 (0.08) -0.23 (0.74) 1.42 (0.15) 1.51 (0.35) 0.85 (0.05) 3.50 (1.13) 0.58 (0.13) 0.78 356 0.93 0.63 10324 0.96 0.85 356 0.97 0.51 10324 0.10 0.68 353 0.84 0.42 10237 0.19 0.67 353 0.84 0.40 10237 0.05 0.63 351 0.80 0.26 10179 0.24 0.62 351 0.79 0.34 10179 0.03 Table 8: This table reports the results of a regression comparing the average total diffusive variance rate of the bucket of firms with the smallest market capitalizations at the end of 2012 with the average variance rates in other size buckets. The notation ’k/1’ is used to refer to the regression of the average diffusive variance rate in bucket k on the rate in bucket 1. Bucket 1 contains the firms with the smallest market capitalizations, bucket 5 those with the largest. In the last column, the variance of GE was removed from the calculation of the average. Standard errors are given in parentheses and are in percentages. Intercept×100 Slope R2 2/1 3/1 4/1 5/1 5/1 (w/o GE) 0.30 (0.09) 0.87 (0.56) 0.34 (0.09) 0.78 (0.60) -0.94 (0.11) 0.59 (0.65) 0.05 (0.08) 0.66 (0.50) 0.25 (0.09) 0.55 (0.56) 0.98 0.98 0.97 0.98 0.97 48 Table 9: This table reports the results of a regression comparing the average idiosyncratic diffusive variance rate of the bucket of firms with the smallest market capitalizations at the end of 2012 with the average variance rates in other size buckets. The notation ’k/1’ is used to refer to the regression of the average diffusive variance rate in bucket k on the rate in bucket 1. Bucket 1 contains the firms with the smallest market capitalizations, bucket 5 those with the largest. In the last column, the variance of GE was removed from the calculation of the average. Standard errors are given in parentheses and are in percentages. Intercept×100 Slope R2 2/1 3/1 4/1 5/1 5/1 (w/o GE) 0.34 (0.11) 0.93 (1.35) 0.18 (0.11) 0.86 (1.32) -0.66 (0.14) 0.57 (1.49) 0.09 (0.09) 0.74 (1.14) 0.24 (0.10) 0.59 (1.25) 0.93 0.92 0.85 0.98 0.86 49 50 All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m All options m ≤ 0.7 0.7 < m ≤ 0.95 0.95 < m ≤ 1.05 1.05 < m ≤ 1.2 m > 1.2 τ ≤ 2m 2m < τ ≤ 6m τ > 6m 45988 5038 18475 8508 9344 4630 10311 19570 16107 48568 3519 16933 9162 9669 9285 10511 20987 17070 XLE 7698 875 3928 2000 860 35 2003 3675 2020 7341 149 2928 2546 1488 234 1887 3588 1866 XLU 7869 1130 3306 1801 1357 275 1807 3585 2477 11617 1401 4678 2352 2371 815 3261 5525 2831 11033 1721 4709 2105 1692 806 3592 4612 2829 11017 1428 4804 2540 1913 332 2835 5195 2987 8251 365 3158 2399 1758 574 1932 3864 2455 Out-of-sample period XLY XLB XLP XLK In-sample period 5609 10959 6411 98 631 347 2176 4252 2345 1725 2690 1447 1284 2202 1495 326 1184 777 1186 2833 1980 2665 5171 2634 1758 2955 1797 11666 1842 4664 2347 2131 682 2846 5368 3452 8323 328 3092 2535 1746 622 1822 3918 2583 XLI 8100 905 3947 2237 980 31 2013 3844 2243 5611 66 2005 2319 1082 139 1314 2744 1553 XLV 19939 2575 6596 3437 4262 3069 4881 9053 6005 10606 956 3783 1865 1954 2048 2949 4615 3042 XLF Table 10: Number of options included in the in-sample (e.g., estimation period) and out-of-sample exercises for each stock. Table 11: This table reports the statistics of the returns of four portfolios that are weekly rebalanced depending on the level of idiosyncratic variance (Panel A) and true idiosyncratic variance (Panel B) of each stock, from the beginning of March 2006 until the end of December 2012. Portfolio 1 contains every week a combination of the 7 stocks with the smallest idiosyncratic variance. Portfolio 4 contains the 7 stocks with the largest idiosyncratic variance. The initial wealth level is 100. The average return, its standard deviation (Std. dev.) and its Sharpe ratio are multiplied by 100. Average return Std. dev. Sharpe ratio 1 2 3 4 0.02 0.07 0.22 0.23 2.02 2.38 2.69 3.76 Panel A 1.21 3.20 8.28 6.37 1 2 3 4 0.03 0.11 0.16 0.25 1.95 2.36 2.72 3.85 Panel B 1.54 4.87 6.05 5.53 51 Skewness Kurtosis -1.16 -0.44 -0.67 -0.16 10.60 6.92 7.46 7.86 -0.81 -0.31 -0.79 -0.25 9.48 5.30 9.03 7.51 Technical Appendix A A.1 Functional Principal Component Analysis Procedure I first construct for every Wednesday in my sample a smooth estimator of the implied volatility surface IVt (m, τ ) over a grid of moneynesses m ∈ [mmin , mmax ] and times-to-maturity τ ∈ [τmin , τmax ], using a non-parametric Nadaraya-Watson estimator as detailed in H¨ardle (1992) and A¨ıt-Sahalia and Lo (1998). The boundaries of the grid are chosen such that enough data points are available over time to accurately intrapolate the IV surface. Following Cont and da Fonsecca (2002), I calculate the weekly variations ∆Xt (m, τ ) = ln IVt (m, τ ) − ln IVt−1 (m, τ ) of the logarithm of the implied volatility at every grid point and consider the random field Ut (m, τ ) = ∆Xt (m, τ ). I assume stationarity and apply a Karhunen-Lo`eve (K-L) decomposition to Ut (m, τ ), which is a generalization of the classic PCA to higher dimensional random fields. Intuitively, the K-L expansion provides a second-moment characterization of random surface in terms of orthogonal functions fk and uncorrelated random variables Uk as follows: U (m, τ ) = N KL X Uk fk (m, τ ). k=1 The fk are the eigenfunctions of the covariance function K(m, τ, m0 , τ 0 ) for (m, τ ) and (m0 , τ 0 ) ∈ A = [mmin , mmax ] × [τmin , τmax ], defined as follows: K(m, τ, m0 , τ 0 ) = cov(U (m, τ ), U (m0 , τ 0 )). The covariance function is numerically computed from the time-series of smooth implied volatility surfaces. Its eigenfunctions result from a spectral decomposition of the function, done by solving the homogeneous Fredholm integral equation of the second kind: Z K(x1 , x2 )fk (x1 )dx1 = λk fk (x2 ), A 52 where the λk are the eigenvalues of the covariance function, x1 and x2 ∈ A. A difficulty of solving the Fredholm equation lies in the availability of eigenfunctions. To reduce the dimensionality of the problem I use as in Cont and da Fonsecca (2002) a Garlekin procedure13 , which expresses the eigenfunctions as a linear combination of basis functions hj : fk (m, τ ) = X aij hj (m, τ ) + . (12) j The coefficients aij define a matrix A. Let scalar product of two surfaces u and v : A → R is defined as: Z hu, vi = u(x)v(x)dx. A The error term is set to be orthogonal to each basis function hj so that one ultimately has to solve for a finite number of equations. The symmetric matrices B and C are defined as: Bij = hhi , hj i, Z Cij = Z dm0 dτ 0 hi (m, τ )K(m, τ, m0 , τ 0 )hj (m0 , τ 0 ) dmdτ A A In practice, each coefficient is calculated numerically using Simpson’s rule of integration. The final problem is summarized in the following matrix eigenvalue problem, where one has to solve for D and A, D being a diagonal matrix with the eigenvalues of the covariance function λk on its main diagonal: CA = DBA. The eigenfunctions are recovered from equation (12) and the principal components processes xk (t) obtained by projecting the random surface Ut on the eigenfunctions fk : xk (t) = hXt − X0 , fk i. 13 Alternative methods involving, e.g., wavelets have been proposed to deal with potentially non-smooth surfaces and processes that exhibit non-stationarity or autocorrelation. See for example Phoon, Huang, and Quek (2002) 53 A.2 Results for the S&P 500 Figure 14: Eigenmodes resulting from the FPCA of weekly S&P 500 options’ implied volatilities from March 1st, 2006 until December 31, 2012. The first eigenmode explains 98%, and the sum of the first four eigenmode explain 99.88% of the variation of the IV surface over time. First eigenmode Second eigenmode 0.04 0.06 0.02 0 0.04 −0.02 0.02 0.5 −0.04 0.5 T 0 0.7 m0.8 0.9 1.1 1 0 T Third eigenmode 0.7 −3 x 10 m0.8 0.9 1 1.1 1 1.1 Fourth eigenmode 15 10 0.01 5 0.005 0 0 −5 0.5 −0.005 −0.01 0.5 1.5 0.4 1 0.3 T 0.2 0.1 0.5 T m 54 0 0.7 m0.8 0.9 Figure 15: Principal component processes resulting from the FPCA of weekly S&P 500 options’ implied volatilities from March 1st, 2006 until December 31, 2012. 14 −2 12 −3 x2 (t) x1 (t) 10 8 −4 −5 6 −6 4 Jan−08 Jan−10 −7 Jan−12 10 2 5 1 0 0 x4 (t) x3 (t) 2 −5 −2 −15 −3 Jan−08 Jan−10 −4 Jan−12 55 Jan−10 Jan−12 Jan−08 Jan−10 Jan−12 −1 −10 −20 Jan−08 B High-frequency data analysis For each stock I denote by ∆ni p = p i − p i−1 the variation of log-price increments over time grid n n i−1 i every day t = 1, ..., T . The following measures of variation of log price returns are calculated , n n based on 5-minute tick data. These measures have been introduced for generic semimartingale processes, see Andersen, Bollerslev, Diebold, and Labys (2003), Bollerslev, Todorov, and Li (2013), Mancini (2009), and used extensively since. The realized variance RVt is defined as the sum of intra-day squared returns, it converges in probability towards the quadratic variation of the underlying return process: RVt = tn+n X |∆ni p|2 →P QV[t,t+1] , i=tn+1 The realized variance can be decomposed into the continuous variation CVt that captures the ”small” movements of the returns, which are likely to be generated by a continuous process, and the jump variation JVt , which captures the larger movements, better represented by a jump process: CVt = tn+n X |∆ni p|2 1{|∆ni p|≤αi n−ω¯ } . i=tn+1 Z t+1 Z P JVt = RVt − CVt → t x2 µ(ds, dx). R µ(., .) refers to the jump measure of the underlying returns. The threshold αi is set following Bollerslev and Todorov (2011) and Bollerslev, Todorov, and Li (2013). The estimated mean and standard deviation of jump sizes under the empirical measure are set to the empirical moments of aggregated intra-day returns that exceed the level αi . 56 C Change of measure The market dynamics are as follows under a risk-neutral measure Q, where the parameters without superscript are either Q-parameters or parameters that are invariant under both measures: q dMt M M Q ZtM + (eZt − 1)dNtM = (r − λM (vtM , m )E [e − 1])dt + vtM − t − dWt Mt− q M M M dvtM = κM (m − v )dt + σ vtM + ytM dNtM t − dBt v v t− M M√ ¯M dmt = κM − mt )dt + σm mt dB m (θ t M with EQ [eZt − 1] = eµ M + 1 (σ M )2 2 − 1 and M (P) dWt M (P) dBt q vtM = −η − dt M (P) M (Q) q κv − κv M (Q) dt = dBt + vtM − σvM M (Q) dWt M M (P) ¯ M (Q) + √mt κm = dB t M (P) ¯ dB t θM (P) = M (Q) − κm M σm dt M (Q) M (Q) θ κm M (P) κm Individual stocks have the following dynamics: dStj Stj− =rdt + j βdif f q q j j M M vt− dWt + vtj− dWtj + (eZt − 1)dNtj − λj (vtj− )EQ [eZt − 1]dt j M j M Q βjump Zt + (eβjump Zt − 1)dNtM − λM (vtM − 1]dt − , mt )E [e q dvtj =βvj dvtM + κjv (θj − vtj− )dt + σvj vtj− dBtj + ytj dNtj . j j + 1 (σ j )2 2 with EQ [eZt − 1] = eµ − 1 and j(P) dWt j(P) dBt q − η vtj− dt q j(P) κv − κjv = dBtj + vtj− dt. σvj = dWtj j 57 D Option pricing Assume that the characteristic functions of the process S˜ takes the following exponential form: h i ˜ ΨS˜T (t, s˜t , vtj , vtM , mt ; ω) := EQ eωST |Ft j ˜ M +χ(T −t)·m +η(T −t) t = eα(T −t)·St +β(T −t)·vt +γ(T −t)·vt , . with ω ∈ C. Let us define the joint Laplace transforms of jumps in returns and variances: j Z j +φM Z M j j 1 j j 2 M M 1 M ] = eφ µ + 2 (φ σ ) eφ µ + 2 (φ σ 1 1 j j M M θy (ψ j , ψ M ) = EQ [eψ y +ψ y ] = . 1 − ψj yj 1 − ψM yM θZ (φj , φM ) = EQ [eφ M )2 Coefficients are functions of the time-to-maturity and satisfy a system of ODEs, ∀t ∈ (0, T ]. The first equation reduces to α(T − t) = α(0) = ω. The remaining ODEs are as follows: 0 β (T − t) = ω −λj1 (θZ (1, 0) 2 1 1 1 − 1) − − β(T − t)κjv + ω 2 + β(T − t)σvj + ωβ(T − t)σvj ρj + 2 2 2 λj1 [θZ (ω, 0)θy (β(T − t), 0) − 1] 1 j 1 j 2 j 2 j M M γ 0 (T − t) = ω −λM (θ (0, β ) − 1) − (β ) − β(T − t)β κ − γ(T − t)κ + ωβdif f + Z 1 v v v jump 2 dif f 2 2 1 2 1 j j M M βvj σvM ρM + ωγ(T − t)βdif β(T − t)βvj σvM + γ(T − t)σvM + ωβ(T − t)βdif f σv ρ + f 2 2 h i j j β(T − t)γ(T − t)βvj (σvM )2 + λM θ (0, ωβ )θ (0, β(T − t)β + γ(T − t)) − 1 y Z 1 v jump h i 1 j j χ0 (T − t) = − ωλM θZ (0, βjump ) − 1 + κM (χ(T − t)σm )2 + 2 v β(T − t)βv + γ(T − t) − χ(T − t)κm + 2 h i j j λM θ (0, ωβ )θ (0, β(T − t)β + γ(T − t)) − 1 y Z 2 v jump h i j η 0 (T − t) = ω r − λj0 (θZ (1, 0) − 1) − λM (θ (0, β ) − 1) + β(T − t)κjv θj + χ(T − t)κm θM + Z 0 jump h i j j M j λ0 [θZ (ω, 0)θy (β(T − t), 0) − 1] + λ0 θZ (0, ωβjump )θy (0, β(T − t)βv + γ(T − t)) − 1 . Boundary conditions are given by α(0) = ω, β(0) = γ(0) = χ(0) = η(0) = 0. 58 E Integrated Risk Premia Under the definition given in equation (8), the IERP can be decomposed into an idiosyncratic component IERP Idio (t, T ) and a market component IERP M arket (t, T ), with: IERP Idio (t, T ) =η j Z EPt T t 1 − 2 IERP M arket (t, T ) Z T Z T j j j j Q P λ (vs )ds λ (vs )ds − E − E [e − 1] E t t Z Z T Z T j j j Q j j(P) P j Q λ (vs )ds − µ E vs ds + µ E vs ds − E vsj ds T Z EP Q Zj j M P =βdif f η Et Z T λ j (vsj )ds t t t t T vsM ds t Z T Z T P M M Q M M − E [e − 1] E λ (vs , ms )ds − E λ (vs , ms )ds t t Z T Z T 1 j M Q M 2 P vs ds − E vs ds − (βdif f ) E 2 t t Z T Z T j M (P) P M M M Q M j + βjump µ E λ (vs , ms )ds − µ E λ (vs , ms )ds . Q j βjump ZM t t The calculation of the IERP therefore amounts to computing the expectation of the integrated variances under the empirical and risk-neutral measures. Due to the affine property of the model, these expectations can be written as linear functions of vtj , vtM and mt . Coefficients are derived by solving the ODE satisfied by f (t, T ) = E[vT ], under P and Q, for vT = vTj and vT = vTM . The ODE is obtained directly from the stochastic differential equation satisfied by the variance processes. For conciseness, coefficients are not provided but available upon request. Similarly, the IVRP can be decomposed into an idiosyncratic component IV RP Idio (t, T ) and a market component IV RP M arket (t, T ), such that 59 . IV RP Idio Z T Z T Q j P j vs ds Et vs ds − Et t t NTj NTj 1 P X X + (Znj )2 (Znj )2 − EQ Et t T −t j j 1 (t, T ) = T −t n=Nt +1 n=Nt +1 and IV RP M arket j 2 (βdif f) Z T Z T Q M P M vs ds (t, T ) = Et vs ds − Et T −t t t NTj NTj j 2 (βjump ) P X X + (ZnM )2 − EQ (ZnM )2 . Et t T −t j j n=Nt +1 n=Nt +1 The expectation of the squared jumps is obtained using the independence between the jump sizes and the Poisson process driving their occurrence time. For example in the case of the individual stock: NTj Z X j 2 j 2 j 2 Et (Zn ) = [(µ ) + (σ ) ] E[λj (vsj )]ds. t n=Ntj +1 F T Model properties In this section I examine the relationship between the betas and the risk-neutral moments of the returns. Let t = t0 < t1 < ... < tn = T be a uniform time grid over a given time period [0, T ], with ∆t = ti − ti−1 , i > 0. The total risk-neutral variance of stock j over [t, T ] is given by14 : "Z j TotalVar (t, T ) = Et T d log Suj − Et [d log Suj ] 2 # t Z = T j Z VarRate (u)du + o t T VarRate (u)du j t where VarRate is the instantaneous variance rate defined in equation (11) and the rest is a function of the characteristics of the jump distributions. As the variance swap rate, the total variance is 14 All expectations are taken under Q. 60 therefore increasing in the betas. I define the risk-neutral skewness rate of stock j as follows: Et 1 SkewRate (t) = lim ∆t→0 ∆t1/2 ∆ log Stj − 3 Et [∆ log Stj ] j Et M = SkewRate ∆ log Stj j (t)(βjump )3 − 2 3/2 Et [∆ log Stj ] VarRateM (t) VarRatej (t) 3/2 + SkewRate Idio(t) VarRateIdio (t) VarRatej (t) 3/2 where VarRateM (t) and SkewRateM (t) are the spot variance and skewness of the market factor, j j and VarRateIdio (t) and SkewRateIdio (t) are those of stock j obtained by setting βjump = βdif f = 0. As µM is typically negative, the market skewness is negative, and pulls the total skewness towards negative values. The idiosyncratic skewness is for typical parameter values close to zero. Note that the instantaneous skewness rate is only non zero because of the jump term. In a diffusion setup, as the third moment of Brownian motion increments is zero, there is no instantaneous skewness. Following Christoffersen, Fournier, and Jakobs (2013), the total skewness of stock j over the time interval [t, T ] is defined as: Et TotalSkewj (t) = Et R R T t T t d log Suj d log Suj − − 3 Et [d log Suj ] 2 3/2 Et [d log Suj ] The total skew can be decomposed similarly to the instantaneous skew rate into an idiosyncratic skew and a market skew, whose diffusive and jump parts are respectively proportional to (βdif f )3 and (βjump )3 . A larger (βdif f )3 pushes the skew to be more negative. The impact of (βjump )3 is, however, not as clear as for the spot skew, because of an additional cross-term that is close to zero for small idiosyncratic jumps. 61 Online Appendix 62
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