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A Very Brief Primer On Bayesian Methods In Evidence, Richard D. Friedman

Articles

I have been asked to write an extremely short explanation of the Bayesian approach to evidentiary issues, for the benefit of those who regard themselves as probabilistically challenged. Although the application of Bayesian probability to evidence has generated a good deal of debate, its use as a heuristic device should not be particularly controversial. Evidence concerns propositions that are uncertain. Accordingly, some concept of probability must play a role. Standards of persuasion, such as "more likely than not" and "beyond a reasonable doubt" are clearly probabilistic, and the definition of relevant evidence, as expressed in Fed. R. Evid. 40 I, …