In this [post] discussed the European put and call price formulas under the Heston Stochastic Volatility model.
There exists an important extension of Heston model to include diffusion jumps, known as Bates Stochastic Volatility Jump (SVJ) model, as referred to in this paper.
What are the option price formulas in SVJ model?
Answer
The Bates model is represented by the bivariate system of stochastic differential equations dSt=(r−q)Stdt+√vtStdW1(t)+StdNtdvt=κ(θ−vt)dt+σ√vtdW2(t)
where EQ[dW1(t)dW2(t)]=ρdt
and Nt is a compound Poisson process with intensity λ and independent jumps J with ln(1+J)˜ N(ln(1+β)−12α2,α2)
The parameters β and α determine the distribution of the jumps and the Poisson process is assumed to be independent of the Wiener processes.By application of delta-hedging argument,we have ∂U∂t+12vtSt2∂2U∂S2+12σ2vt∂2U∂v2+ρσvtSt∂2U∂S∂v+(r−q−λˉk)St∂U∂S+κ(θ−vt)∂U∂v−rU+IU=0(1)
where IU=λ∫∞0[U(Sξ,v,t)−U(S,v,t)]g(ξ)dξ
g(ξ)=1√2παξe−12α2(lnξ−m)2
m=ln(1+β)−12α2
ˉk=e12α2+m−1
It should be noted that closed-form solutions for vanilla-option payoff do exist but PIDE (1) is easily approximated by Numerical Methods.
close form solution
I edited my Answer for emcor.
- Dynamic of St under historical measure dStSt=(μ−λˉJ)dt+√vtdW1(t)+JdN(t)dvt=κ(θ−vt)dt+σ√vtdW2(t),where EP[dW1(t)dW2(t)]=ρdt,Nt is a compound Poisson process with intensity λ and independent jumps J with ln(1+J)˜ N(ln(1+ˉJ)−12α2,α2).The parameters ˉJ and α determine the distribution of the jumps and the Poisson process is assumed to be independent of the Wiener processes.
- Change measure: P→Q dStSt=(r−q−λ∗¯J∗)dt+√vtdWQ1(t)+J∗dN∗(t)dvt=κ∗(θ∗−vt)dt+σ√vtdWQ2(t),where EQ[dWQ1(t)dWQ2(t)]=ρdtκ∗=κ+ξθ∗=κθκ+ξ,such that ξ is volatility market price and J∗=J+JEP[ΔJwJw]ˉJ∗=ˉJ+Cov(J,ΔJwJw)1+EP[ΔJwJw].Where ΔJwJw is random percentage jump conditional on a jump occurring and dJwJw is percentage shock in the absence of jump.
- Note that,when ξ=0 we have κ∗=κ and θ∗=θ. We set ξ=0, because when we estimate the risk-neutral parameters to price options we do not need to estimate ξ. Also, when ΔJw/Jw→0 thus we have J∗=J and ˉJ∗=ˉJ.
- let xt=lnSt then C(t,St,vt,J,K,T)=StP1−Ke−rτP2where,for j=1,2 Pj(xt,vt;xT,lnK)=12+1π∞∫0Re(e−iϕlnKfj(ϕ;t,x,v)iϕ)dϕfj(ϕ;vt,xt)=exp[Cj(τ,ϕ)+Dj(τ,ϕ)vt+iϕxt+Ξj]Ξj=λ∗τ(1+κ∗)uj+12[(1+κ∗)ϕeα2(ujϕ+0.5ϕ2)−1],such that Cj(τ,ϕ)=(r−q−λ∗ˉκ∗)ϕτ−κ∗θ∗τσ2(ρσϕ−βj−γj)−2κ∗θ∗τσ2ln(1+12(ρσϕ−βj−γj)1−eγjτγj)Dj(τ,ϕ)=−2(ujϕ+12ϕ2)ρσϕ−βj+γj1+e1−γjτ1−e1−γjτγj=√(ρσϕ−βj)2−2σ2(ujϕ+0.5ϕ2)and u1=12,u2=−12,β1=κ∗−ρσ,β2=κ∗
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