Bayesian statistics

Bayesian statistics is a subset of the field of statistics in which the evidence about the true state of the world is expressed in terms of degrees of belief or, more specifically, Bayesian probabilities. Such an interpretation is only one of a number of interpretations of probability and there are other statistical techniques that are not based on "degrees of belief". One formulation of the "key ideas of Bayesian statistics" is "that probability is orderly opinion, and that inference from data is nothing other than the revision of such opinion in the light of relevant new information."