Malliavin calculus with time dependent coefficients and application to nonlinear filtering

Springer Science and Business Media LLC - Tập 86 - Trang 203-223 - 1990
Patrick Florchinger1
1U.R.A. C.N.R.S. No 399, Département de Mathématiques, U.F.R. M.I.M., Université de Metz, Metz Cedex, France

Tóm tắt

In this paper, we prove, using Malliavin calculus, that under a local Hörmander condition the solution of a stochastic differential equation with time depending coefficients admits aC ∞ density with respect to Lebesgue measure. An application of this result to nonlinear filtering is developed in this paper to prove the existence of aC ∞ density for the filter associated with a correlated system whose observation is one dimensional with unbounded coefficients.

Tài liệu tham khảo

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