- Bayes theorem
- A probability principle set forth by the English mathematician Thomas Bayes (1702-1761). Bayes' theorem is of value in medical decision-making and some of the biomedical sciences. Bayes' theorem is employed in clinical epidemiology to determine the probability of a particular disease in a group of people with a specific characteristic on the basis of the overall rate of that disease and of the likelihood of that specific characteristic in healthy and diseased individuals, respectively. A common application of Bayes' theorem is in clinical decision making where it is used to estimate the probability of a particular diagnosis given the appearance of specific signs, symptoms, or test outcomes. For example, the accuracy of the exercise cardiac stress test in predicting significant coronary artery disease (CAD) depends in part on the "pre-test likelihood" of CAD: the "prior probability" in Bayes' theorem. In technical terms, in Bayes' theorem the impact of new data on the merit of competing scientific hypotheses is compared by computing for each hypothesis the product of the antecedent plausibility and the likelihood of the current data given that particular hypothesis and rescaling them so that their total is unity. In Bayes' theorem: {{}}The antecedent plausibility is termed the "prior probability." The likelihood of the current data given that particular hypothesis is called the "conditional probability." The rescaled values are called the "posterior probabilities."
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(bāz) [Thomas*Bayes,*English mathematician, 1702â€“1761] see under*theorem.*

*Medical dictionary.
2011.*

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**Bayes' theorem**— In probability theory, Bayes theorem (often called Bayes law after Thomas Bayes) relates the conditional and marginal probabilities of two random events. It is often used to compute posterior probabilities given observations. For example, a… … Wikipedia**Bayes-Theorem**— Das Bayestheorem (auch Satz von Bayes) ist ein Ergebnis der Wahrscheinlichkeitstheorie, benannt nach dem Mathematiker Thomas Bayes. Es gibt an, wie man mit bedingten Wahrscheinlichkeiten rechnet. Inhaltsverzeichnis 1 Formel 2 Interpretation 3… … Deutsch Wikipedia**Bayes Theorem**— Das Bayestheorem (auch Satz von Bayes) ist ein Ergebnis der Wahrscheinlichkeitstheorie, benannt nach dem Mathematiker Thomas Bayes. Es gibt an, wie man mit bedingten Wahrscheinlichkeiten rechnet. Inhaltsverzeichnis 1 Formel 2 Interpretation 3… … Deutsch Wikipedia**Bayes' Theorem**— A formula for determining conditional probability named after 18th century British mathematician Thomas Bayes. The theorem provides a way to revise existing predictions or theories given new or additional evidence. In finance, Bayes’… … Investment dictionary**Bayes' theorem**— /beɪz ˈθɪərəm/ (say bayz thearruhm) noun Statistics a method of measuring the degree of belief that can be attached to a proposition, based on the relevance of ascertainable facts. Also, Bayes law. {named posthumously after Thomas Bayes, 1701–61 … Australian English dictionary**Bayes' theorem**— noun Etymology: Thomas Bayes died 1761 English mathematician Date: 1865 a theorem about conditional probabilities: the probability that an event A occurs given that another event B has already occurred is equal to the probability that the event B … New Collegiate Dictionary**Bayes' theorem**— noun Statistics a theorem expressing the conditional probability of each of a set of possible causes for a given observed outcome in terms of the known probability of each cause and the conditional probability of the outcome of each cause.… … English new terms dictionary**Bayes' theorem**— noun (statistics) a theorem describing how the conditional probability of a set of possible causes for a given observed event can be computed from knowledge of the probability of each cause and the conditional probability of the outcome of each… … Useful english dictionary**Bayes' theorem**— /bayz, bay ziz/, Statistics. a theorem describing how the conditional probability of each of a set of possible causes, given an observed outcome, can be computed from knowledge of the probability of each cause and of the conditional probability… … Universalium**Bayes’ theorem**— Stats a probability theorem that allows statisticians continually to revise the probability of an event according to new evidence … The ultimate business dictionary