Point process

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A point process is a type of stochastic process that is widely used in many fields of applied mathematics, such as queueing theory and computational neuroscience.

[edit] Definition

A point process is a map \xi:\Omega\to K from a probability space Ω to a set K consisting of finite subsets of a metric space X.




In applied mathematics the space X is usually the real line, which is often interpreted as time. Thus a collection of points in X may be interpreted as a sequence of event times, and for each outcome \omega \in \Omega,\quad \quad\xi(\omega) is a sequence of event times \quad (t_1, t_2, .., t_N), where the number N of event times may be different for different \, \omega.

[edit] conditional intensity function

A conditional intensity function of a point process is a function \, \lambda (t | H_{t}) defined as


\lambda(t| H_{t})=\lim_{\Delta t\to 0}\frac{1}{\Delta t}{P}(\mbox{One spike occurs in the time-interval}\,[t,t+\Delta t]\,|\, H_t) ,


where \, H_tdenotes the history of event times preceding time \,t.

[edit] See also

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