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Stochastic volatility jump models

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Class of financial models with stochastic volatility and jumps
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Stochastic Volatility Jump Models (SVJ models) are a class of mathematical models inquantitative finance that combinestochastic volatility dynamics with discontinuousjumps in asset prices. These models aim to more accurately reflect the empirical characteristics of financial markets, particularly those that deviate from the assumptions of classical models such as theBlack–Scholes model.[1]

SVJ models are capable of capturingstylized facts commonly observed in asset returns, including heavy tails (leptokurtosis), skewness, abrupt price changes, and the persistence ofvolatility clustering.[2]These models also provide a more realistic explanation forimplied volatility surfaces—such as volatility smiles and skews—which are inadequately modeled by constant-volatility frameworks.[3]

By introducing both a stochastic variance process and a jump component—typically modeled via aPoisson process or more generalLévy processes—SVJ models allow for more flexible and accurate pricing offinancial derivatives, especiallyoptions and volatility-linked instruments.[4]

Overview

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Stochastic volatility jump models extend both purestochastic volatility models—such as theHeston model—andjump diffusion models—such as theMerton model—by integrating the two components into a unified framework. In these models, the asset price is driven by a continuous-time stochastic variance process and is also subject to discontinuous jumps, typically modeled using aPoisson process or more generalLévy processes.[5]

This dual structure enables SVJ models to account for both persistent volatility fluctuations and sudden, unexpected market movements. The stochastic component captures long-term variability andvolatility clustering, while the jump component reflects abrupt price changes due to market events, earnings surprises, or systemic shocks.[6]

Fundamental hypotheses

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Stochastic volatility jump models rely on several core assumptions that extend the classical framework ofItô diffusion models to accommodate more complex market behavior. These include:

  • Price jumps arrive according to aPoisson process (or compoundLévy process), with jump sizes modeled by a separate distribution such as log-normal or exponential, introducing discontinuities in asset paths.[9]
  • The market is assumed to be arbitrage-free and ofteninformationally efficient, although the presence of jumps introduces market incompleteness, making perfect hedging impossible with standard instruments.[10]

Mathematical formulation

[edit]
Comparison of GBM and SVJ paths, showing volatility clustering and price jumps.

A typical stochastic volatility jump (SVJ) model assumes that the asset priceSt{\displaystyle S_{t}} evolves under a risk-neutral measureQ{\displaystyle \mathbb {Q} } according to the following system of stochastic differential equations (SDEs):

dSt=μStdt+vtStdWtS+(Jt1)StdNt,dvt=κ(θvt)dt+σvvtdWtv{\displaystyle {\begin{aligned}dS_{t}&=\mu S_{t}\,dt+{\sqrt {v_{t}}}\,S_{t}\,dW_{t}^{S}+(J_{t}-1)\,S_{t-}\,dN_{t},\\dv_{t}&=\kappa (\theta -v_{t})\,dt+\sigma _{v}{\sqrt {v_{t}}}\,dW_{t}^{v}\end{aligned}}}

where:

Alternatively, in some credit risk and asymmetric modeling frameworks, the jump size is modeled as exponentially distributed:ΔlogStExp(η){\displaystyle \Delta \log S_{t}\sim {\text{Exp}}(\eta )}, whereη>0{\displaystyle \eta >0} is the rate parameter.

The stochastic variancevt{\displaystyle v_{t}} captures volatility clustering and long-term uncertainty, while the jump component introduces discontinuous movements in prices, enhancing the model's ability to replicate empirical asset return distributions.[12]

The inclusion of correlationρ{\displaystyle \rho } between the asset return and its variance introduces the so-called leverage effect, a common feature in equity markets.[13]

Notable models

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Several variants of stochastic volatility jump models have been developed to capture different market phenomena and to allow for greater flexibility in pricing derivatives.

Bates model

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The Bates model combines theHeston model for stochastic volatility with Merton-style jumps in asset prices. It preserves the mean-reverting variance process of the Heston model while adding a Poisson-driven jump component:

dSt=μStdt+vtStdWtS+(Jt1)StdNt,dvt=κ(θvt)dt+σvvtdWtv{\displaystyle {\begin{aligned}dS_{t}&=\mu S_{t}\,dt+{\sqrt {v_{t}}}S_{t}\,dW_{t}^{S}+(J_{t}-1)S_{t-}\,dN_{t},\\dv_{t}&=\kappa (\theta -v_{t})\,dt+\sigma _{v}{\sqrt {v_{t}}}\,dW_{t}^{v}\end{aligned}}}

whereJt{\displaystyle J_{t}} is the jump multiplier andNt{\displaystyle N_{t}} is a Poisson process.[14]

SVJJ model

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The SVJJ model generalizes the Bates framework by allowing for jumps in both the asset price and the variance process:

dSt=μStdt+vtStdWtS+(JtS1)StdNtS,dvt=κ(θvt)dt+σvvtdWtv+JtvdNtv{\displaystyle {\begin{aligned}dS_{t}&=\mu S_{t}\,dt+{\sqrt {v_{t}}}S_{t}\,dW_{t}^{S}+(J_{t}^{S}-1)S_{t-}\,dN_{t}^{S},\\dv_{t}&=\kappa (\theta -v_{t})\,dt+\sigma _{v}{\sqrt {v_{t}}}\,dW_{t}^{v}+J_{t}^{v}\,dN_{t}^{v}\end{aligned}}}

Here,JtS{\displaystyle J_{t}^{S}} andJtv{\displaystyle J_{t}^{v}} are jump sizes in return and variance, with separate Poisson processesNtS{\displaystyle N_{t}^{S}} andNtv{\displaystyle N_{t}^{v}}.[15]

Duffie–Pan–Singleton (DPS) model

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The DPS model adopts anaffine process formulation, where the joint process of returns and volatility evolves under a state-space representation:

dXt=K(ΘXt)dt+ΣXtdWt+dJt{\displaystyle dX_{t}=K(\Theta -X_{t})\,dt+\Sigma {\sqrt {X_{t}}}\,dW_{t}+dJ_{t}}

Here,Xt{\displaystyle X_{t}} is a vector of state variables (e.g., log-price and variance), andJt{\displaystyle J_{t}} is a multivariate jump process. The model is designed to preserve analytical tractability.[16]

Barndorff-Nielsen–Shephard (BNS) model

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The BNS model introduces a non-GaussianOrnstein–Uhlenbeck process for stochastic variance driven by a Lévy subordinator:

dvt=λvtdt+dZt{\displaystyle dv_{t}=-\lambda v_{t}\,dt+dZ_{t}}

The return process is then modeled as:

dSt=μdt+vtdWt{\displaystyle dS_{t}=\mu \,dt+{\sqrt {v_{t}}}\,dW_{t}}

whereZt{\displaystyle Z_{t}} is a non-decreasing Lévy process (e.g., Gamma process) andvt{\displaystyle v_{t}} captures jumps in volatility without requiring jumps in price.[17]

Applications

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Stochastic volatility jump (SVJ) models are widely used in financial engineering and quantitative risk management due to their ability to replicate observed features in market data that cannot be captured by simpler models.

One of the primary applications is in the pricing and hedging offinancial derivatives, particularlyoptions. SVJ models are able to generate more realisticimplied volatility surfaces, capturing both thevolatility smile and skew commonly observed in equity and foreign exchange markets.[18]

SVJ models also play a key role involatility forecasting, as they provide a dynamic framework that accounts for both persistent volatility clustering and sudden shifts due to market events. These features are essential for accurate computation ofvalue at risk (VaR),expected shortfall, and other risk metrics used by financial institutions.

In addition, SVJ frameworks are applied in the modeling ofcredit risk, where asset values are subject to abrupt changes, and ininterest rate modeling where jumps may capture macroeconomic shocks or policy announcements.

The flexibility of SVJ models also makes them useful inmodel calibration, particularly when fitting option prices across multiple strikes and maturities. Techniques such as theFourier transform, characteristic function methods (e.g., Carr–Madan), andMarkov Chain Monte Carlo (MCMC) are often used to estimate model parameters efficiently.[19]

Option pricing

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SVJ models are particularly useful for pricingEuropean andAmerican options in markets where volatility is not constant and sudden price changes occur. The presence of jumps and stochastic variance allows the model to produce implied volatility surfaces that better match observed market data—especially the volatility smile and skew patterns.

Option prices under SVJ models are often computed using Fourier transform techniques, leveraging the characteristic function of the log-price process. Methods such as theCarr–Madan formula and the COS method are commonly employed for computational efficiency.[20][21]

For American-style or path-dependent options, numerical methods such as finite difference schemes, Monte Carlo simulation with jump adjustments, or regression-based Longstaff–Schwartz methods are often used.[22]

Overall, SVJ models improve pricing accuracy, especially for short-dated and out-of-the-money options, where the impact of jumps is more pronounced.

Advantages and limitations

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Stochastic volatility jump (SVJ) models offer several advantages over traditional models such as theBlack–Scholes model and theHeston model without jumps.

One major advantage is their ability to jointly captureleptokurtosis (fat tails),skewness, and sudden large movements in asset prices, all of which are empirically observed in financial markets.[23] SVJ models also allow for improved calibration to market option prices, enabling more accurate pricing and hedging of exotic derivatives.

However, these models come with certain limitations. The inclusion of both stochastic volatility and jump components increases model complexity and can lead tooverfitting if not properly constrained. Parameter estimation can be computationally intensive and may require advanced numerical techniques such asmaximum likelihood estimation,Kalman filtering, orBayesian inference.

Another challenge lies in the identification of jump components in high-frequency data, as distinguishing between sudden changes due to jumps and those from high volatility alone can be statistically ambiguous.[24]

Despite these drawbacks, SVJ models remain an important part of the quantitative finance toolkit, especially in applications where market realism and tail-risk modeling are critical.

Variants and extensions

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Several extensions of the basic stochastic volatility jump (SVJ) framework have been proposed to better capture empirical phenomena or improve tractability in pricing and calibration.

Bates model

[edit]

The Bates model extends theHeston model by incorporating jumps in the asset price. It is widely used in option pricing due to its semi-closed-form solution via Fourier inversion.[25]

The model dynamics under the risk-neutral measureQ{\displaystyle \mathbb {Q} } are given by:dSt=μStdt+vtStdWtS+(Jt1)StdNt,dvt=κ(θvt)dt+σvvtdWtv{\displaystyle {\begin{aligned}dS_{t}&=\mu S_{t}\,dt+{\sqrt {v_{t}}}S_{t}\,dW_{t}^{S}+(J_{t}-1)S_{t-}\,dN_{t},\\dv_{t}&=\kappa (\theta -v_{t})\,dt+\sigma _{v}{\sqrt {v_{t}}}\,dW_{t}^{v}\end{aligned}}}

SVJJ model (stochastic volatility with jumps in volatility and price)

[edit]

The SVJJ model introduces jumps not only in the asset price but also in the volatility process:dvt=κ(θvt)dt+σvvtdWtv+ηvdNtv,{\displaystyle dv_{t}=\kappa (\theta -v_{t})\,dt+\sigma _{v}{\sqrt {v_{t}}}\,dW_{t}^{v}+\eta _{v}\,dN_{t}^{v},}wheredNtv{\displaystyle dN_{t}^{v}} is a Poisson process driving jumps in volatility. This provides more flexibility in capturing volatility bursts and market turmoil events.[26]

BNS model (Barndorff-Nielsen–Shephard)

[edit]

TheBarndorff-Nielsen–Shephard model is a non-Gaussian SVJ model where the volatility follows an Ornstein–Uhlenbeck-type process driven by a Lévy subordinator. It enables a purely jump-driven volatility process and is used in high-frequency volatility estimation.[27]

Calibration techniques

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Calibrating stochastic volatility jump (SVJ) models involves estimating both continuous diffusion parameters and jump-related components from market data. This process is crucial for ensuring the model fits observed option prices or high-frequency asset paths.

One common approach is to calibrate SVJ models toimplied volatility surfaces by minimizing the pricing error across a range of strikes and maturities. Techniques such as least-squares minimization or maximum likelihood estimation are often used. The model's characteristic function enables efficient option pricing via Fourier inversion methods such as theCarr–Madan formula.[28]

Alternatively, when working with time-series data (e.g., asset returns), likelihood-based estimation or theKalman filter and its nonlinear extensions (e.g., particle filters) may be employed to estimate hidden volatility states and jump intensities.[29]

In Bayesian frameworks,Markov chain Monte Carlo (MCMC) methods are used to infer the posterior distributions of model parameters, especially useful when models are highly nonlinear or contain latent processes.

The choice of calibration method depends on the application: derivative pricing typically uses cross-sectional calibration to option prices, while risk management and volatility forecasting often rely on historical time series and filtering techniques.

References

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  1. ^Merton, Robert C. (1976). "Option pricing when underlying stock returns are discontinuous".Journal of Financial Economics.3 (1–2):125–144.doi:10.1016/0304-405X(76)90022-2.hdl:1721.1/1899.
  2. ^Eraker, Bjørn; Johannes, Michael; Polson, Nicholas (2003). "The impact of jumps in volatility and returns".The Journal of Finance.58 (3):1269–1300.doi:10.1111/1540-6261.00566.
  3. ^Gatheral, Jim (2006).The Volatility Surface: A Practitioner's Guide. Wiley Finance.ISBN 978-0471792512.
  4. ^Duffie, Darrell; Pan, Jun; Singleton, Kenneth J. (2000). "Transform analysis and asset pricing for affine jump-diffusions".Econometrica.68 (6):1343–1376.doi:10.1111/1468-0262.00164.
  5. ^Duffie, Darrell; Pan, Jun; Singleton, Kenneth J. (2000). "Transform analysis and asset pricing for affine jump-diffusions".Econometrica.68 (6):1343–1376.doi:10.1111/1468-0262.00164.
  6. ^Pan, Jun (2002). "The jump-risk premia implicit in options: Evidence from an integrated time-series study".Journal of Financial Economics.63 (1):3–50.doi:10.1016/S0304-405X(01)00092-2 (inactive 14 August 2025).{{cite journal}}: CS1 maint: DOI inactive as of August 2025 (link)
  7. ^Duffie, Darrell; Pan, Jun; Singleton, Kenneth J. (2000). "Transform analysis and asset pricing for affine jump-diffusions".Econometrica.68 (6):1343–1376.doi:10.1111/1468-0262.00164.
  8. ^Heston, Steven L. (1993). "A closed-form solution for options with stochastic volatility with applications to bond and currency options".The Review of Financial Studies.6 (2):327–343.doi:10.1093/rfs/6.2.327.
  9. ^Merton, Robert C. (1976). "Option pricing when underlying stock returns are discontinuous".Journal of Financial Economics.3 (1–2):125–144.doi:10.1016/0304-405X(76)90022-2.hdl:1721.1/1899.
  10. ^Eraker, Bjørn (2004)."Do stock prices and volatility jump? Reconciling evidence from spot and option markets".The Journal of Finance.59 (3):1367–1403.doi:10.1111/j.1540-6261.2004.00665.x.
  11. ^Merton, Robert C. (1976). "Option pricing when underlying stock returns are discontinuous".Journal of Financial Economics.3 (1–2):125–144.doi:10.1016/0304-405X(76)90022-2.hdl:1721.1/1899.
  12. ^Duffie, Darrell; Pan, Jun; Singleton, Kenneth J. (2000). "Transform analysis and asset pricing for affine jump-diffusions".Econometrica.68 (6):1343–1376.doi:10.1111/1468-0262.00164.
  13. ^Heston, Steven L. (1993). "A closed-form solution for options with stochastic volatility with applications to bond and currency options".The Review of Financial Studies.6 (2):327–343.doi:10.1093/rfs/6.2.327.
  14. ^Bates, David S. (1996). "Jumps and stochastic volatility: Exchange rate processes implicit in Deutsche mark options".The Review of Financial Studies.9 (1):69–107.doi:10.1093/rfs/9.1.69.
  15. ^Eraker, Bjørn (2001). "MCMC analysis of diffusion models with application to finance".Journal of Business and Economic Statistics.19 (2):177–191.doi:10.1198/073500101316970403.hdl:11250/164095.
  16. ^Duffie, Darrell; Pan, Jun; Singleton, Kenneth J. (2000). "Transform analysis and asset pricing for affine jump-diffusions".Econometrica.68 (6):1343–1376.doi:10.1111/1468-0262.00164.
  17. ^Barndorff-Nielsen, Ole E.; Shephard, Neil (2001). "Non-Gaussian Ornstein–Uhlenbeck-based models and some of their uses in financial economics".Journal of the Royal Statistical Society Series B: Statistical Methodology.63 (2):167–241.doi:10.1111/1467-9868.00282.
  18. ^Eraker, Bjørn (2004). "Do Stock Prices and Volatility Jump? Reconciling Evidence from Spot and Option Prices".Journal of Finance.59 (3):1367–1403.doi:10.1111/j.1540-6261.2004.00665.x.
  19. ^Duffie, Darrell; Pan, Jun; Singleton, Kenneth J. (2000). "Transform analysis and asset pricing for affine jump-diffusions".Econometrica.68 (6):1343–1376.doi:10.1111/1468-0262.00164.
  20. ^Carr, Peter; Madan, Dilip (1999). "Option valuation using the fast Fourier transform".Journal of Computational Finance.2 (4):61–73.doi:10.21314/JCF.1999.043.
  21. ^Fang, Feng; Oosterlee, Cornelis W. (2008). "A novel pricing method for European options based on Fourier–cosine series expansions".SIAM Journal on Scientific Computing.31 (2):826–848.doi:10.1137/080718061.
  22. ^Glasserman, Paul (2004).Monte Carlo Methods in Financial Engineering. Springer.ISBN 978-0387004518.
  23. ^Bates, David S. (1996). "Jumps and stochastic volatility: Exchange rate processes implicit in Deutsche Mark options".The Review of Financial Studies.9 (1):69–107.doi:10.1093/rfs/9.1.69.
  24. ^Jacod, Jean; Todorov, Viktor (2009). "Testing for jumps in a discretely observed process".Annals of Statistics.37 (1):435–477.doi:10.1214/07-AOS568.
  25. ^Bates, David S. (1996). "Jumps and stochastic volatility: Exchange rate processes implicit in Deutsche Mark options".The Review of Financial Studies.9 (1):69–107.doi:10.1093/rfs/9.1.69.
  26. ^Duffie, Darrell; Pan, Jun (2001). "Analytical Value-at-Risk with Jumps and Stochastic Volatility".Finance and Stochastics.5 (2):155–180.doi:10.1007/PL00013592.
  27. ^Barndorff-Nielsen, Ole E.; Shephard, Neil (2001). "Non-Gaussian Ornstein–Uhlenbeck-based models and some of their uses in financial economics".Journal of the Royal Statistical Society Series B: Statistical Methodology.63 (2):167–241.doi:10.1111/1467-9868.00282.
  28. ^Carr, Peter; Madan, Dilip (1999). "Option valuation using the fast Fourier transform".Journal of Computational Finance.2 (4):61–73.doi:10.21314/JCF.1999.043.
  29. ^Johannes, Michael (2004). "The statistical and economic role of jumps in continuous-time interest rate models".Journal of Finance.59 (1):227–260.doi:10.1111/j.1540-6261.2004.00632.x (inactive 14 August 2025).{{cite journal}}: CS1 maint: DOI inactive as of August 2025 (link)
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