Diagnostic Utility: Experimental Demonstrations and Replications of Powerful Question Effects in High‐Stakes Deception Detection

The concept of diagnostic utility was used to create questions that would differentially affect deception detection accuracy. Six deception detection studies show that subtle differences in questioning produced accuracy rates that were predictably, substantially, and reliably above and below chance. The first 3 detection studies demonstrate that diagnostically useful questioning can reliably achieve accuracy rates over 70% with student and experienced judges. The fourth and fifth experiments demonstrated negative diagnostic utility among federal investigators but not students. The final experiment crossed 3 sets of interview questions with experience. Strong question effects produced a swing in accuracy from 32 to 73%. A questioning by experience interaction was also obtained.     

Are absolute frequencies,relative frequencies,or both effective in reducing cognitive biases?

Biases in probabilistic reasoning are affected by alterations in the presentation of judgment tasks. In our experiments, students made likelihood judgments that an event was produced by various causes. These judgments were made in terms of probability, relative frequency or absolute frequency on a full or a pruned list of causes. When they had little personal experience of the event (causes of death), the pruning bias was smaller with relative frequencies than with absolute frequencies or probabilities. When they had more personal experience of the event (missing a lecture), the bias was less with both types of frequency than with probability but still lowest with relative frequency. We suggest that likelihood information is usually stored as relative frequencies when it has been obtained from public sources but that it is based on event counts when it is derived from personal experience. Copyright © 2000 John Wiley & Sons, Ltd.