Logical Methods in Computer Science (Dec 2014)

Algorithmic randomness for Doob's martingale convergence theorem in continuous time

  • Bjørn Kjos-Hanssen,
  • Paul Kim Long V. Nguyen,
  • Jason Rute

DOI
https://doi.org/10.2168/LMCS-10(4:12)2014
Journal volume & issue
Vol. Volume 10, Issue 4

Abstract

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We study Doob's martingale convergence theorem for computable continuous time martingales on Brownian motion, in the context of algorithmic randomness. A characterization of the class of sample points for which the theorem holds is given. Such points are given the name of Doob random points. It is shown that a point is Doob random if its tail is computably random in a certain sense. Moreover, Doob randomness is strictly weaker than computable randomness and is incomparable with Schnorr randomness.

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