The LR does not exist

More than 40years ago, De Finetti warned that probability is a misleading misconception when regarded as objectively existing exterior to the mind. According to De Finetti, probabilities are necessarily subjective, and quantify our belief in the truth of events in the real world. Given evidence of a shared feature of a trace and an accused, we apply this framework to assign an evidential value to this correspondence. Dividing 1 by the objectively existing proportion of the population sharing that feature would give that evidential value − expressed as a likelihood ratio (LR) − only if that proportion were known.
Source: Science and Justice - Category: Forensic Medicine Authors: Tags: Position paper Source Type: research