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Revision difference : adapted process
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Suppose $T$ is a well-ordered set with minimal value $0$. Let $\lbrace X_t \mid t\in T\rbrace$ be a stochastic process defined on a probability space $(\Omega,\mathcal{F},P)$ and $\lbrace \mathcal{F}_t\rbrace$ a filtration (an increasing sequence of sigma subalgebras of $\mathcal{F}$). Then the process $\lbrace X_t\rbrace$ is said to be \emph{adapted to} the filtration $\lbrace \mathcal{F}_t\rbrace$ if for each $t$, $X_t$ is \PMlinkname{$\mathcal{F}_t$-measurable}{MathcalFMeasurableFunction}: Suppose $T$ is a well-ordered set with minimal value $0$. Let $\lbrace f_t \mid t\in T\rbrace$ be a stochastic process defined on a probability space $(\Omega,\mathcal{F},P)$ and $\lbrace \mathcal{F}_t\rbrace$ a filtration (an increasing sequence of sigma subalgebras of $\mathcal{F}$). Then the process $\lbrace f_t\rbrace$ is said to be \emph{adapted to} the filtration $\lbrace \mathcal{F}_t\rbrace$ if for each $t$, $f_t$ is \PMlinkname{$\mathcal{F}_t$-measurable}{MathcalFMeasurableFunction}:
$$X_t^{-1}(B)\in \mathcal{F}_t\mbox{ for each Borel set }B\in\mathbb{R}.$$ $$f_t^{-1}(B)\in \mathcal{F}_t\mbox{ for each Borel set }B\in\mathbb{R}.$$
A stochastic process is an \emph{adapted process} if it is adapted to some filtration. A stochastic process is an \emph{adapted process} if it is adapted to some filtration.