Focusing Techniques: A Shortcut to Improving Probability Judgments?

A recurrent finding of judgment research is that people often ignore important kinds of information, such as the base rate of some occurrence. Focusing techniques attempt to improve judgment in inferential problems by helping people to attend to all available information. One such technique is Subjective Sensitivity Analysis, which requires people to consider what judgments they would make were a given item of information to assume each of a series of possible values. A second focusing technique is Isolation Analysis, which requires people to consider what judgment they would make were each item of information to have been the only one available, prior to making a summary judgment based on all given information. In several experimental tasks, both techniques promoted the use of otherwise neglected kinds of information. Unfortunately, they also promoted usage of normatively irrelevant information. Similar effects were obtained both with a more modest technique, Minimal Focusing, which merely instructs subjects to “attend to all the information,” and a more ambitious one, Balanced SSA, which applies subjective sensitivity analysis to both items of information, rather than just to the one that is customarily ignored. All in all, the data suggest that these techniques do not actually enhance people's understanding of the role of base-rate considerations, but merely encourage the use of whatever information is presented. Improving judgment requires more extensive education than can be imparted through mechanical employment of focusing techniques.