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About: Conditional Probability

Module by: Paul E Pfeiffer. E-mail the author

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Name: Conditional Probability
ID: m23252
Language: English (en)
Summary: The probability P(A) of an event A is a measure of the likelihood that the event will occur on any trial. New, but partial, information determines a conditioning event C , which may call for reassessing the likelihood of event A. For a fixed conditioning event C, this new assignment to all events constitutes a new probability measure. In addition, because of the way it is derived from the original, or prior, probability, the conditional probability measure has a number of special properties which are important in applications. Determination of the conditioning event is key.
Subject: Mathematics and Statistics
Keywords: Bayes' rule, Compound trials, Conditional probability measure, Conditioning event, Law of total probability, Product rule, Repeated conditioning, Reversal of conditioning
License: Creative Commons Attribution License CC-BY 3.0

Authors: Paul E Pfeiffer (
Copyright Holders: Paul E Pfeiffer (
Maintainers: Paul E Pfeiffer (, Daniel Williamson (, C. Sidney Burrus (

Latest version: 1.7 (history)
First publication date: Apr 14, 2009 4:10 pm -0500
Last revision to module: Sep 18, 2009 12:18 pm -0500


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Version History

Version: 1.7 Sep 18, 2009 12:18 pm -0500 by Daniel Williamson
added google analytics tracking code

Version: 1.6 Jul 27, 2009 11:44 am -0500 by Daniel Williamson
disjoint union fix

Version: 1.5 Jun 19, 2009 11:03 am -0500 by Daniel Williamson
m-file fixes, supplemental links, metadata updated

Version: 1.4 Jun 9, 2009 5:03 pm -0500 by Daniel Williamson
updated links, images, and accessibility

Version: 1.3 May 26, 2009 4:17 pm -0500 by Daniel Williamson
fixed module names, and updated content structure

Version: 1.2 May 14, 2009 11:20 am -0500 by Paul E Pfeiffer

Version: 1.1 May 13, 2009 11:51 am -0500 by Paul E Pfeiffer

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