Infinitesimal generator of stochastic integral of a diffusion process with deterministic jumps

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I have little knowledge on jump processes, so I am trying to make an analogous case of a normal stochastic process here but I my intuition says that I am doing something wrong

Suppose you have a stochastic process $(S_t)_t$ such that

$$dS_t = S_{t^-} r_t dt + (S_{t^-} - A_t) \sigma_t dW_t - \sum_k (S_t^{-} \beta_k + \alpha_k) \delta_{\tau_k}(t) dt$$

where $A_t, r_t$ are deterministic processes, $\tau_k$ are deterministic times, and $\alpha_k, \beta_k$ are real sequences.

I want to define the process

$$M_t = \frac{1}{t} \int_0^t S_u du$$

and calculate the generator of the process $(t, S_t, M_t)$. I suppose I know the generator of the process $(t, S_t)$. How the jumps of $S_t$ affect $M_t$?

Can I just add $\frac{S - M}{t} \frac{\partial}{\partial M}$ in generator of $(t, S_t)$ to find the generator of $(t, S_t, M_t)$ or do I need to account the jumps in some way?