Refining Conditional Probative Value

Conditional Probative Value: Neoclassicism without Myth

The misquantification of probative value.

D. Davis and W. C. Follette (2002) purport to show that when "the base rate" for a crime is low, the probative value of "characteristics known to be strongly associated with the crime ... will be virtually nil." Their analysis rests on the choice of an arbitrary and inopposite measure of the probative value of evidence. When a more suitable metric is used (e.g., a likelihood ratio), it becomes ...

Probative Blindness and False Assurance about Safety

Safety activities may provide assurance of safety even where such assurance is unwarranted. This phenomenon – which we will call “probative blindness” – is evident both in hindsight analysis of accidents and in the daily practice of safety work. The purpose of this paper is to describe the phenomenon of probative blindness. We achieve this by distinguishing probative blindness from other phenom...

Interviewing children versus tossing coins: accurately assessing the diagnosticity of children's disclosures of abuse.

We describe a Bayesian approach to evaluating children's abuse disclosures and review research demonstrating that children's disclosure of genital touch can be highly probative of sexual abuse, with the probative value depending on disclosure spontaneity and children's age. We discuss how some commentators understate the probative value of children's disclosures by: confusing the probability of...

If the Shoe Fits They Might Acquit: The Value of Forensic Science Testimony

The probative value of forensic science evidence (such as a shoeprint) varies widely depending on how the evidence and hypothesis of interest is characterized. This paper uses a likelihood ratio (LR) approach to identify the probative value of forensic science evidence. It argues that the “evidence” component should be characterized as a “reported match,” and that the hypothesis component shoul...