Bayes' theorem


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Related to Bayes' theorem: conditional probability

Bayes' theorem

[¦bāz ′thir·əm]
(mathematics)
A theorem stating that the probability of a hypothesis, given the original data and some new data, is proportional to the probability of the hypothesis, given the original data only, and the probability of the new data, given the original data and the hypothesis. Also known as inverse probability principle.
References in periodicals archive ?
As explained in the FDA's Guidance document, prior information about a topic that you wish to investigate in more detail can be combined with new data using Bayes' Theorem. Symbolically, p(A|B) = p(B|A) x p(A)/p(B)
(152) However, "objective Bayesians" (153) use Bayes' theorem without eliciting prior probabilities from subjective beliefs, avoiding the charge of subjectivism.
Bayesian inference essentially provides a probabilistic computational framework based on Bayes' theorem to quantify uncertainties associated with model parameters and model classes by specifying the probability density function (PDF) (or probabilistic distribution) of uncertain model parameters and relative model probabilities of competing candidate model classes [14, 17, 18].
Mathematical shorthand for a conditional probability is P(A|B), read as "probability of A given B." Concerning terrorism, we can express Bayes' Theorem for the probability of identifying a terrorist using the TSA's new behavioral testing screen as follows:
Bayes' theorem can be expressed in terms of the odds-ratios between two hypotheses (1):
From a subjective approach, the property of exchangeability allows to solve some controversies regarding the relationships between probability and frequency and the Bayes' theorem, which constitutes the theoretical foundation of the learning process based on experience that allows to coherently relate assignments of probabilities for different information sets, transforming statistical inference in a particular case of inductive reasoning (5).
The methodology proposed in this article utilizes an expert judgment model within a Bayesian framework for the more complex case of continuous probability distributions, The most general form of Bayes' Theorem applies to discrete probability distributions, and relates the conditional and prior probabilities of two events using the following equation,
This volume contains 10 chapters that review recently reported short interfering RNA (siRNA) design guidelines and clarifies the problems concerning the guidelines, as well as detailing an effective method for selecting siRNA target sequences from many possible candidate sequences using Bayes' theorem, the development of a durable RNAi therapy for cancer and viral infections, and the structure, application, and therapeutic challenges of siRNA.
* probability (you didn't think that you could avoid that, did you?; but they do introduce the really useful Bayes' theorem)
A naive Bayes classifier is a simple probabilistic classifier based on applying Bayes' theorem with strong (naive) independence assumptions.
Under the heading "Urinalysis Data and Hair Analysis Data," Bayes' theorem was expressed as follows: