Home Dissecting skewness under affine jump-diffusions
Article
Licensed
Unlicensed Requires Authentication

Dissecting skewness under affine jump-diffusions

  • Fang Zhen ORCID logo EMAIL logo and Jin E. Zhang
Published/Copyright: November 8, 2019

Abstract

This paper derives the theoretical skewness in a five-factor affine jump-diffusion model with stochastic variance and jump intensity, and jumps in prices and variances. Numerical analysis shows that all of the uncertainties in this model affect skewness. The information regarding jumps in prices is mainly reflected in the short-term skewness. The skewness for other maturities carries the information that is highly correlated with variance. Furthermore, the theoretical VIX and skewness under a simplified five-factor model are used to fit the market risk-neutral volatility and skewness sequentially. The fitting performances are better than traditional double-jump models.

JEL Classification: G12; G13

Award Identifier / Grant number: 023063022002/010

Award Identifier / Grant number: 71771199

Funding statement: Fang Zhen has been supported by the Research Fund from the Central University of Finance and Economics (Funder Id: http://dx.doi.org/10.13039/501100002942, Project No. 023063022002/010) and the Program for Innovation Research in Central University of Finance and Economics. Jin E. Zhang has been supported by an establishment grant from the University of Otago and the National Natural Science Foundation of China grant (Funder Id: http://dx.doi.org/10.13039/501100001809, Project No. 71771199).

A Appendix

A.1 Third central moment

The asset log-return is modelled by

(42)dlnSt=(α12vtλtμf(x))dt+vtdBtS+xdNtλtμxdt,
(43)dvt=κv(mtvt)dt+σvvtdBtv+ydNtλtμydt,
(44)dmt=κm(θmmt)dt+σmmtdBtm,
(45)dλt=κλ(ntλt)dt+σλλtdBtλ
(46)dnt=κn(θnnt)dt+σnntdBtn,

where f(x)=ex1x and μf(x) denotes its expectation. The continuously compounded return from the current time t to the future time T is defined as

(47)RtTlnSTSt=tT[(α12vuμf(x)λu)du+vtdBuS+xdNuλuμxdu].

Its conditional expectation at time t is then given by

(48)Et(RtT)=tT(α12Et(vu)μf(x)Et(λu))du.

Thus, adopting the notations in Zhang et al. (2017), we decompose the de-meaned return into four parts as follows:

(49)RtTEt(RtT)=XT12YT+ZTμf(x)ΛT,

where

(50)XTtTvudBuS,
(51)YTtT[vuEt(vu)]du,
(52)ZTtT(xdNuλuμxdu),
(53)ΛTtT[λuEt(λu)]du.

Converting the variance process described by Equation (43) into the integral form gives

(54)vs=κvκvκmmsκmθmκvκm+eκv(st)[vt(κvκvκmmtκmθmκvκm)]+tseκv(su)[σvvudBuv+ydNuλuμyduκvσmκvκmmudBum].

The conditional expectation of vs at time t (s > t) is given by

(55)Et(vs)=κvEt(ms)κvκmκmθmκvκm+eκv(st)[vt(κvmtκvκmκmθmκvκm)],

where Et(ms)=θm+eκm(st)(mtθm). Hence, the de-meaned instantaneous variance is

(56)vsEt(vs)=tseκv(su)[σvvudBuv+ydNuλuμyduκvκvκmσmmudBum]+κvκvκmtseκm(su)σmmudBum.

Conducting interchange of the order of integration, we decompose YT into three parts:

(57)YT=YTH+YTJ+YTM.

where

(58)YsHσvts1eκv(Tu)κvvudBuv,s=T,
(59)YsJts1eκv(Tu)κv(ydNuλuμydu),
(60)YsMκvσmκvκmts(1eκm(Tu)κm1eκv(Tu)κv)mudBum.

Note that YsH, YsJ and YsM are martingales. YT could be decomposed in the way shown in Equation (57) only at time T. The martingale property of YsH, YsJ and YsM is crucial when computing the moments of the continuously compounded return. See Zhang et al. (2017) for more details. Since the structure of λt is similar to that of vt and there is no jumps in jump intensity, we decompose ΛT into two parts:

(61)ΛT=ΛTH+ΛTN.

where

(62)ΛsHσλts1eκλ(Tu)κλλudBuλ,s=T,
(63)ΛsNκλσnκλκnts(1eκn(Tu)κn1eκλ(Tu)κλ)nudBun.

Note that, in our setup, there are seven risk resources, which are the diffusive risk XT in the asset return process, the Heston-type diffusive risks YTH and ΛTH in the instantaneous variance and jump intensity processes, the variance jump risk YTJ, the diffusive risks YTM and ΛTN in the long-term mean processes of variance and jump intensity, and the price jump risk ZT. Making use of the independence between the Brownian motions {dBtS,dBtv}, dBtm, dBtλ, dBtn, and the Poisson counter dNt, we split the third moment of RtT into four parts in the following manner:

(64)TCM=Et[(RtTEt(RtT))3]=TCMH+TCMJ+TCMM+TCMN,

where

(65)TCMHEt[(XT12YTH)3],
(66)TCMJEt[(ZT12YTJμf(x)ΛTH)3]+3Et[(ZT12YTJ)(XT12YTH)2],
(67)TCMM18Et[(YTM)3]32Et[YTM(XT12YTH)2],
(68)TCMNμf(x)3Et[(ΛTN)3]3μf(x)Et[ΛTN(ZT12YTJμf(x)ΛTH)2].

Zhang et al. (2017) explicitly derives the Heston-type third moment as follows:

(69)TCMH=Et[XT3]32Et[XT2YTH]+34Et[XT(YTH)2]18Et[(YTH)3],

where the third and co-third moments of XT and YTH are given by

(70)Et[XT3]=3ρσvtTA1(κv,u)Et(vu)du,
(71)Et[XT2YTH]=σv2tT[A12(κv,u)+2ρ2A2(κv,u)]Et(vu)du,
(72)Et[XT(YTH)2]=ρσv3tT[2A1(κv,u)A2(κv,u)+A3(κv,u)]Et(vu)du,
(73)Et[(YTH)3]=3σv4tTA1(κv,u)A3(κv,u)Et(vu)du,

and the weights are given by

(74)A1(κv,u)=1eκvτκv,τ=Tu,
(75)A2(κv,u)=1eκvτκvτeκvτκv2,
(76)A3(κv,u)=1e2κvτ2κvτeκvτκv3.

Next, we derive the third moment stemming from the risk in the stochastic long-term variance as follows:

(77)TCMM=18Et[(YTM)3]32Et[YTM(XT12YTH)2].

Before deriving TCMM, we need the following results.

Lemma 1

The correlations between YsM and {ms,vs} are given by

(78)Et(YsMms)=κvσm2tseκm(su)B1(κv,κm,u)Et(mu)du,
(79)Et(YsMvs)=κv2σm2κvκmts[eκm(su)eκv(su)]B1(κv,κm,u)Et(mu)du,

where

(80)B1(κv,κm,u)=A1(κm,u)A1(κv,u)κvκm.
Proof.

See Appendix A.1.1.    □

Using Ito’s Lemma and the martingale property of Xu, YuH and YuM (u > t), we have

(81)Et[YTM(XT12YTH)2]=Et[tTd(YuM(Xu12YuH)2)]=Et[tTYuM(d(Xu12YuH))2]=tTEt(YuMvu)(1ρσvA1(κv,u)+14σv2A12(κv,u))du.

Plugging Equation (79) into the above equation, we obtain

(82)Et[YTM(XT12YTH)2]=κv2σm2tTB1(κv,κm,u)2Et(mu)duρσvκv2σm2κvκmtT[B1(κv,κm,u)A2(κv,u)]B1(κv,κm,u)Et(mu)du+σv2κv2σm24(κvκm)tT[B2(κv,κm,u)A3(κv,u)]B1(κv,κm,u)Et(mu)du,

where

(83)B2(κv,κm,u)=B1(κv,κm,u)B1(κv,2κv,u)κvκm/2.

Using Ito’s Lemma and the martingale property of YuM, we have

(84)Et[(YTM)3]=Et[tTd(YuM)3]=3Et[tTYuM(dYuM)2]=3κv2σm2tTEt(YuMmu)B1(κv,κm,u)2du.

Plugging Equation (78) into the above equation, we obtain

(85)Et[(YTM)3]=3κv3σm4(κvκm)2tTB3(κv,κm,u)B1(κv,κm,u)Et(mu)du,

where

(86)B3(κv,κm,u)=A3(κm,u)A2(κm,u)+B1(2κv,κm,u)A1(κv,u)A1(κm,u)κv/2.

Next, we obtain the third moment resulting from the jumps in prices and variance as well as the uncertainty in the instantaneous jump intensity. Making using of the properties of compound Poisson processes and the previous results on the Heston-type third moment, we have

(87)TCMJ=Et[(ZT12YTJ)3]+3Et[(ZT12YTJ)(XT12YTH)2]3μf(x)Et[ΛTH(ZT12YTJ)2)]μf(x)3Et(ΛTH)3,

where the third moment of ZT12YTJ is

(88)Et[(ZT12YTJ)3]=tT(μx332μx2yA1(κv,u)+34μxy2A12(κv,u)μy38A13(κv,u))Et(λu)du,

the co-third moment of ZT12YTJ and XT12YTH is

(89)Et[(ZT12YTJ)(XT12YTH)2]=tT[μxyμy22A1(κv,u)](A1(κv,u)ρσvA2(κv,u)+14σv2A3(κv,u))Et(λu)du,

the co-third moment of ΛTH and ZT12YTJ is

(90)Et[ΛTH(ZT12YTJ)2]=σλ2tTA1(κλ,u)(μx2A1(κλ,u)μxyB1(κv,κλ,u)+μy24B2(κv,κλ,u))Et(λu)du,

the third moment of ΛTH is

(91)Et[(ΛTH)3]=3σλ4tTA1(κλ,u)A3(κλ,u)Et(λu)du,

and the expectations of functions of jump sizes are μx3=3μxσx2+μx3, μx2y=(μx2+σx2)μy, μxy2=2μxμy2, μy3=6μy3, μx2=μx2+σx2, μxy=μxμy, μy2=2μy2, μf(x)=eμx+12σx21μx.

Finally, we obtain the third moment coming from the uncertainty in the stochastic long-term jump intensity as follows:

(92)TCMN=μf(x)3Et[(ΛTN)3]3μf(x)Et[ΛTN(ZT12YTJμf(x)ΛTH)2],

where the co-third moment of ZT12YTJμf(x)ΛTH and ΛTN is

(93)Et[ΛTN(ZT12YTJμf(x)ΛTH)2]=μx2κλ2σn2tTB1(κλ,κn,u)2Et(nu)duμxyκλ2σn2κλκntT[B1(κv,κn,u)B1(κv,κλ,u)]B1(κλ,κn,u)Et(nu)du+μy2κλ2σn24(κλκn)tT[B2(κv,κn,u)B2(κv,κλ,u)]B1(κλ,κn,u)Et(nu)du+μf(x)2κλ2σλ2σn2κλκntT[B2(κλ,κn,u)A3(κλ,u)]B1(κλ,κn,u)Et(nu)du,

and the third moment of ΛTN is

(94)Et[(ΛTN)3]=3κλ3σn4(κλκn)2tTB3(κλ,κn,u)B1(κλ,κn,u)Et(nu)du.

A.1.1 Proof of lemma 1

Using Ito’s Lemma and the martingale property of YuM, we have

(95)Et(YsMms)=Et[tsd(YuMmu)]=Et[ts(mudYuM+YuMdmu+dYuMdmu)]=κmtsEt(YuMmu)du+κvσm2κvκmts[A1(κm,u)A1(κv,u)]Et(mu)du,

Solving the above ordinary differential equation (ODE) gives

(96)tsEt(YuMmu)du=κvσm2κvκmtseκm(sr)tr[A1(κm,u)A1(κv,u)]Et(mu)dudr=κvσm2ts1eκm(su)κmB1(κv,κm,u)Et(mu)du.

Differentiating the above result with respect to s yields Equation (78).

Similarly, using Ito’s Lemma and the martingale property of YuM, we have

(97)Et(YsMvs)=Et[tsd(YuMvu)]=Et[ts(vudYuM+YuMdvu+dYuMdvu)]=κvtsEt(YuMvu)du+κvtsEt(YuMmu)du.

Solving the above ODE gives

(98)tsEt(YuMvu)du=κv2σm2κvκmtseκv(sr)tr1eκm(ru)κm[A1(κm,u)A1(κv,u)]Et(mu)dudr=κv2σm2κvκmts[1eκm(su)κm1eκv(su)κv]B1(κv,κm,u)Et(mu)du.

Differentiating the above result with respect to s yields Equation (79).

A.2 Second central moment

Adopting the same notations as those used for computing the third moment in the Appendix A.1, the second central moment of the continuously compounded return is given by

(99)Et[(RtTEt(RtT))2]=VARH+VARJ+VARM+VARN,

where

(100)VARH=Et[(XT12YTH)2]=tT[1ρσvA1(κv,u)+14σv2A12(κv,u)]Et(vu)du,
(101)VARJ=Et[(ZT12YTJμf(x)ΛTH)2]=tT[μx2μxyA1(κv,u)+μy24A12(κv,u)+μf(x)2σλ2A12(κλ,u)]Et(λu)du,
(102)VARM=14Et[(YTM)2]=κv2σm24tTB1(κv,κm,u)2Et(mu)du,
(103)VARN=μf(x)2Et[(ΛTN)2]=μf(x)2κλ2σn2tTB1(κλ,κn,u)2Et(nu)du.

References

Amaya, D., P. Christoffersen, K. Jacobs, and A. Vasquez. 2015. “Does Realized Skewness Predict the Cross-Section of Equity Returns?” Journal of Financial Economics 118: 135–167.10.1016/j.jfineco.2015.02.009Search in Google Scholar

Bakshi, G., C. Cao, and Z. Chen. 1997. “Empirical Performance of Alternative Option Pricing Models.” Journal of Finance 52: 2003–2049.10.1111/j.1540-6261.1997.tb02749.xSearch in Google Scholar

Bakshi, G., N. Kapadia, and D. Madan. 2003. “Stock Return Characteristics, Skew Laws, and the Differential Pricing of Individual Equity Options.” Review of Financial Studies 16: 101–143.10.1093/rfs/16.1.0101Search in Google Scholar

Barndorff-Nielsen, O. E., and N. Shephard. 2004. “Power and Bipower Variation with Stochastic Volatility and Jumps.” Journal of Financial Econometrics 2: 1–37.10.1093/jjfinec/nbh001Search in Google Scholar

Black, F., and M. Scholes. 1973. “The Pricing of Options and Corporate Liabilities.” Journal of Political Economy 81: 637–654.10.1142/9789814759588_0001Search in Google Scholar

Boyer, B., T. Mitton, and K. Vorkink. 2009. “Expected Idiosyncratic Skewness.” Review of Financial Studies 23: 169–202.10.1093/rfs/hhp041Search in Google Scholar

Chang, B. Y., P. Christoffersen, and K. Jacobs. 2013. “Market Skewness Risk and the Cross Section of Stock Returns.” Journal of Financial Economics 107: 46–68.10.1016/j.jfineco.2012.07.002Search in Google Scholar

Chen, J., H. Hong, and J. C. Stein. 2001. “Forecasting Crashes: Trading Volume, Past Returns, and Conditional Skewness in Stock Prices.” Journal of Financial Economics 61: 345–381.10.3386/w7687Search in Google Scholar

Christoffersen, P., S. Heston, and K. Jacobs. 2009. “The Shape and Term Structure of the Index Option Smirk: Why Multifactor Stochastic Volatility Models Work so Well.” Management Science 55: 1914–1932.10.1287/mnsc.1090.1065Search in Google Scholar

Conrad, J., R. F. Dittmar, and E. Ghysels. 2013. “Ex Ante Skewness and Expected Stock Returns.” Journal of Finance 68: 85–124.10.1111/j.1540-6261.2012.01795.xSearch in Google Scholar

Dennis, P., and S. Mayhew. 2002. “Risk-Neutral Skewness: Evidence from Stock Options.” Journal of Financial and Quantitative Analysis 37: 471–493.10.2307/3594989Search in Google Scholar

Duffie, D., J. Pan, and K. Singleton. 2000. “Transform Analysis and Asset Pricing for Affine Jump-Diffusions.” Econometrica 68: 1343–1376.10.3386/w7105Search in Google Scholar

Egloff, D., M. Leippold, and L. Wu. 2010. “The Term Structure of Variance Swap Rates and Optimal Variance Swap Investments.” Journal of Financial and Quantitative Analysis 45: 1279–1310.10.1017/S0022109010000463Search in Google Scholar

Eraker, B., M. Johannes, and N. Polson. 2003. “The Impact of Jumps in Volatility and Returns.” Journal of Finance 58: 1269–1300.10.1111/1540-6261.00566Search in Google Scholar

Friesen, G. C., Y. Zhang, and T. S. Zorn. 2012. “Heterogeneous Beliefs and Risk-Neutral Skewness.” Journal of Financial and Quantitative Analysis 47: 851–872.10.1017/S0022109012000269Search in Google Scholar

Harvey, C. R., and A. Siddique. 2000. “Conditional Skewness in Asset Pricing Tests.” Journal of Finance 55: 1263–1295.10.1111/0022-1082.00247Search in Google Scholar

Heston, S. L. 1993. “A Closed-Form Solution for Options with Stochastic Volatility with Applications to Bond and Currency Options.” Review of Financial Studies 6: 327–343.10.1093/rfs/6.2.327Search in Google Scholar

Kozhan, R., A. Neuberger, and P. Schneider. 2013. “The Skew Risk Premium in the Equity Index Market.” Review of Financial Studies 26: 2174–2203.10.1093/rfs/hht039Search in Google Scholar

Kraus, A., and R. H. Litzenberger. 1976. “Skewness Preference and the Valuation of Risk Assets.” Journal of Finance 31: 1085–1100.10.1111/j.1540-6261.1976.tb01961.xSearch in Google Scholar

Lee, K. 2016. “Probabilistic and Statistical Properties of Moment Variations and Their Use in Inference and Estimation Based on High Frequency Return Data.” Studies in Nonlinear Dynamics and Econometrics 20: 19–36.10.1515/snde-2014-0037Search in Google Scholar

Luo, X., and J. E. Zhang. 2012. “The Term Structure of Vix.” Journal of Futures Markets 32: 1092–1123.10.1002/fut.21572Search in Google Scholar

Merton, R. C. 1976. “Option Pricing when Underlying Stock Returns are Discontinuous.” Journal of Financial Economics 3: 125–144.10.1016/0304-405X(76)90022-2Search in Google Scholar

Nakajima, J. 2013. “Stochastic Volatility Model with Regime-Switching Skewness in Heavy-Tailed Errors for Exchange Rate Returns.” Studies in Nonlinear Dynamics and Econometrics 17: 499–520.10.1515/snde-2012-0021Search in Google Scholar

Neuberger, A. 2012. “Realized Skewness.” Review of Financial Studies 25: 3423–3455.10.1093/rfs/hhs101Search in Google Scholar

Zhang, J. E., and Y. Xiang. 2008. “The Implied Volatility Smirk.” Quantitative Finance 8: 263–284.10.1080/14697680601173444Search in Google Scholar

Zhang, J. E., F. Zhen, X. Sun, and H. Zhao. 2017. “The Skewness Implied in the Heston Model and its Application.” Journal of Futures Markets 37: 211–237.10.1002/fut.21801Search in Google Scholar


Supplementary Material

The online version of this article offers supplementary material (DOI: https://doi.org/10.1515/snde-2018-0086).


Published Online: 2019-11-08

© 2020 Walter de Gruyter GmbH, Berlin/Boston

Downloaded on 10.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/snde-2018-0086/html
Scroll to top button