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arXiv · 1209.3180

Filtered Azéma martingales

Umut Çetin
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Abstract

We study the optional projection of a standard Brownian motion on the natural filtration of certain kinds of observation processes. The observation process, $Y$, is defined as a solution of a stochastic differential equation such that it reveals some (possibly noisy) information about the signs of the Brownian motion when $Y$ hits 0. As such, the associated optional projections are related to Azéma's martingales which are obtained by projecting the Brownian motion onto the filtration generated by observing its signs.

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Umut Çetin. 2012-09-14. Filtered Azéma martingales. https://arxiv.org/abs/1209.3180

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