Interpretations =============== Bayesian interpretation ----------------------- * Probability measures a *degree of belief*. * For proposition A and evidence B, * P(A), the *prior*, is the initial degree of belief in A. * P(A|B), the *posterior*, is the degree of belief having accounted for B. * the quotient P(B|A)/P(B) represents the support B provides for A. Frequentist interpretation -------------------------- * Probability measures a *proportion of outcomes*. * For example, suppose an experiment is performed many times. * P(A), the proportion of outcomes with property A. * P(B), that with property B. * P(B|A), the proportion of outcomes with property B *out of* outcomes with property A. * P(A|B), the proportion of those with A *out of* those with B.