Progressive enlargement of filtration with initial times
نویسندگان
چکیده
The preservation of the semi-martingale property in a progressive enlargement of filtration has been studied by many authors. Most of them focus on progressive enlargement with a honest time, allowing for semi-martingale invariance and simple decomposition formulas. However, times allowing for semi-martingale invariance in initial enlargements preserve as well this property in progressive enlargements. This paper is devoted to the related canonical decomposition of the semi-martingales. Examples are given in credit risk modelling.
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