Belief that drug usage in the United States is increasing when it is really decreasing: An example of the availability heuristic

Abstract

The availability heuristic is a cognitive rule of thumb in which probability of events is judged based on how readily they come to mind (Tversky & Kahneman, 1974). This heuristic can lead to misjudgments when the event is emphasized in the media but actually occurs less frequently than would seem to be the case. The present study asked 104 college students if drug usage in the United States was increasing or decreasing over the past several years, and found they were significantly likely to say it was increasing (p < .001). However, data from the National Household Survey on Drug Abuse, a nationwide sample of 9,259 subjects in households throughout the United States, shows that drug usage has been declining. The students’ perceptions appear to show the working of the availability heuristic. © 1993, Psychonomic Society, Inc.. All rights reserved.