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3.10 Stochastic Volatility Model with Normal Inverse Gaussian Jumps

4.1.1 Stochastic Volatility Model

4.1.1 Stochastic Volatility Model

Under the risk-neutral measure Q, the equation (3.1) can be rewritten as following dyt =

where µ is the drift term which is a constant. The stochastic volatility vtfollows a mean-reverting square root process with long term level ˜θ = κ+hκθ

2, the speed of adjustment is

˜

κ = κ + h2, the variation coefficient of the diffusion volatility is σv, h1 is the price risk premium and h2 is the volatility risk premium. Moreover, dWy,tQ and dWv,tQ, are a pair of correlated Wiener processes with correlation coefficient ρdt, i.e., dWy,tQ ∼ N (0, dt), dWv,tQ ∼ N (0, dt) and Corr

dWy,tQ, dWv,tQ



= ρdt. The detail proof are shown in the Appendix A.

4.1.2 Stochastic Volatility Model with Merton Jumps

Under risk-neutral measure Q, the equation (3.5) can be rewritten as following dyt=

where µ is the drift term which is a constant. The stochastic volatility vtfollows a mean-reverting square root process with long term level ˜θ = κ+hκθ

2, the speed of adjustment is

˜

κ = κ + h2, the variation coefficient of the diffusion volatility is σv, h1 is the price risk premium and h2 is the volatility risk premium. Moreover, dWy,tQ and dWv,tQ, are a pair of correlated Wiener processes with correlation coefficient ρdt, i.e., dWy,tQ ∼ N (0, dt), dWv,tQ ∼ N (0, dt) and Corr

dWy,tQ, dWv,tQ

= ρdt. The return jump dJy,tQ = ξy,tdNy,tQ, the jump size ξy,t is a random variable, dNy,tQ is used to depict the number of the return jump which follows a Poisson process with the intensity λQy which is a constant, i.e., dNy,tQ ∼ P oisson λQydt, and MJQ

y is the compensator of the return jump and the average jump amplitude, i.e., MJQy = EQ The risk-neutral parameters of Merton jumps are

λQ = λyeγh3+12h23δ2, γQ = γ + h3δ2, δQ= δ

The detail proof are shown in the Appendix B.

4.1.3 Stochastic Volatility Model with Independent Merton Jumps

Under the risk-neutral measure Q, the equation (3.9) can be rewritten as following dyt=

where µ is the drift term which is a constant. The stochastic volatility vtfollows a mean-reverting square root process with long term level ˜θ = κ+hκθ

2, the speed of adjustment is

˜

κ = κ + h2, the variation coefficient of the diffusion volatility is σv, h1 is the price risk premium and h2 is the volatility risk premium. Moreover, dWy,tQ and dWv,tQ, are a pair of correlated Wiener processes with correlation coefficient ρdt, i.e., dWy,tQ ∼ N (0, dt), dWv,tQ ∼ N (0, dt) and Corr

dNy,tQ is used to depict the number of the return jump which follows a Poisson process with the intensity λQy which is a constant, i.e., dNy,tQ ∼ P oisson λQydt, and MJQ

y is the compensator of the return jump and the average jump amplitude, i.e., MJQ

y = EP

The compound Poisson process of volatility jump, dJv,t = ξv,tdNv,t = d PNv,t

j=1 ξv,tj  , where the volatility jump size ξv,t is a random variable which follows the exponential distribution with mean µv, i.e. ξv,t∼ exp (µv), dNv,t is used to depict the number of the volatility jump which follows a Poisson process with the intensity λv which is a constant, i.e., dNv,t ∼ P oisson (λvdt). The risk-neutral parameters of Merton jumps are

λQ = λyeγh3+12h23δ2, γQ = γ + h3δ2, δQ= δ The detail proof are shown in the Appendix C.

4.1.4 Stochastic Volatility Model with Correlated Merton Jumps

Under risk-neutral measure Q, the equation (3.13) can be rewritten as following dyt=

where µ is the drift term which is a constant. The stochastic volatility vtfollows a mean-reverting square root process with long term level ˜θ = κ+hκθ

2, the speed of adjustment is

˜

κ = κ + h2, the variation coefficient of the diffusion volatility is σv, h1 is the price risk premium and h2 is the volatility risk premium. Moreover, dWy,tQ and dWv,tQ, are a pair of correlated Wiener processes with correlation coefficient ρdt, i.e., dWy,tQ ∼ N (0, dt), dWv,tQ ∼ N (0, dt) and Corr

y is the compensator of the return jump and the average jump amplitude, i.e., MJQy = EQ the volatility jump size ξv,tis a random variable which follows the exponential distribution with mean µQv, i.e. ξv,t ∼ exp µQv, dNtQ is used to depict the number of the volatility jump which follows a Poisson process with the intensity λQ which is a constant, i.e., dNtQ ∼ P oisson λQdt. The risk-neutral parameters of Merton jumps and volatility jumps are

λQ = λy· eh3γ+12h23δ2

1 − h3ρJµv, γQ = γ + ρJξv,t+ h3δ2, δQ = δ, µQv = µv 1 − h3ρJµv The detail proof are shown in the Appendix D.

4.1.5 Stochastic Volatility Model with Double-Exponential Jumps

Under risk-neutral measure Q, the equation (3.17) can be rewritten as following dyt=

where µ is the drift term which is a constant. The stochastic volatility vtfollows a mean-reverting square root process with long term level ˜θ = κ+hκθ

2, the speed of adjustment is

˜

κ = κ + h2, the variation coefficient of the diffusion volatility is σv, h1 is the price risk

premium and h2 is the volatility risk premium. Moreover, dWy,tQ and dWv,tQ, are a pair of correlated Wiener processes with correlation coefficient ρdt, i.e., dWy,tQ ∼ N (0, dt), dWv,tQ ∼ N (0, dt) and Corr

dWy,tQ, dWv,tQ

= ρdt. The return jump dJy,tQ = ξy,tdNy,tQ, the jump size ξy,t is a random variable, dNy,tQ is used to depict the number of the return jump which follows a Poisson process with the intensity λQy which is a constant, i.e., dNy,tQ ∼ P oisson λQydt, and MJQ

y is the compensator of the return jump and the average jump amplitude, i.e., MJQy = EP

The risk-neutral parameters of Double-Exponential jumps are λQ = λy

The detail proof are shown in the Appendix E.

4.1.6 Stochastic Volatility Model with Independent Double-Exponential Jumps

Under risk-neutral measure Q, the equation (3.21) can be rewritten as following dyt=

where µ is the drift term which is a constant. The stochastic volatility vtfollows a mean-reverting square root process with long term level ˜θ = κ+hκθ

2, the speed of adjustment is

˜

κ = κ + h2, the variation coefficient of the diffusion volatility is σv, h1 is the price risk premium and h2 is the volatility risk premium. Moreover, dWy,tQ and dWv,tQ, are a pair of correlated Wiener processes with correlation coefficient ρdt, i.e., dWy,tQ ∼ N (0, dt), dWv,tQ ∼ N (0, dt) and Corr

dWy,tQ, dWv,tQ

= ρdt. The return jump dJy,tQ = ξy,tdNy,tQ, the jump size ξy,t is a random variable, dNy,tQ is used to depict the number of the return

jump which follows a Poisson process with the intensity λQy which is a constant, i.e., dNy,tQ ∼ P oisson λQydt, and MJQ

y is the compensator of the return jump and the average jump amplitude, i.e., MJQ

y = EP 

The compound Poisson process of volatility jump, dJv,t = ξv,tdNv,t = d PNv,t

j=1 ξv,tj  , where the volatility jump size ξv,t is a random variable which follows the exponential distribution with mean µv, i.e. ξv,t∼ exp (µv), dNv,t is used to depict the number of the volatility jump which follows a Poisson process with the intensity λv which is a constant, i.e., dNv,t ∼ P oisson (λvdt). The risk-neutral parameters of double-exponential jumps and volatility jumps are

λQ = λy

The detail proof are shown in the Appendix F.

4.1.7 Stochastic Volatility Model with Correlated Double-Exponential