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Posterior Probability

Posterior probability is the updated probability after incorporating evidence.

Definition

Posterior probability is the updated probability you get after applying evidence to a prior probability. It is computed through Bayes theorem using odds and a likelihood ratio.

Why it matters

Posterior probability provides a disciplined way to update beliefs when new information arrives, instead of reacting emotionally to headlines.

Common pitfalls

Treating evidence as certainty: Likelihood ratios shift odds, they do not guarantee outcomes.