Young adults shopped for music compact disks in a five store simulated Internet mall. In stock probability in all stores was constant at 0.80, but each store was associated with either a 0.5, 2, 4, 8, or 16 second to a feedback message indicating whether a particular disk was in stock or out of stock at that time. Working under a successive choice schedule, in Phase I subjects' behavior was in quantitative concordance with the Delay-Reduction Hypothesis (DRH), and in Phase II, when a changeover delay was added, subjects' behavior conformed more closely to the predictions of the DRH. Hyperbolic discount functions provided the best fit to the data. This study extends the synthesis of foraging theory and operant psychology, known as behavioral ecology, to human consumption in an affluent post-industrial culture, and provides the basis for an experimental analysis of human consumption. Extensions to research in consumer behavior, marketing strategy, and behavior on Internet services are proposed. Copyright © 2000 John Wiley & Sons, Ltd.