“PERHAPS IT WOULD BE BETTER NOT TO KNOW EVERYTHING”1

Abstract

The advent of statistical methods for evaluating the data of individual‐subject designs invites a comparison of the usual research tactics of the group‐design paradigm and the individual‐subject‐design paradigm. That comparison can hinge on the concept of assigning probabilities of Type 1 and Type 2 errors. Individual‐subject designs are usually interpreted with implicit, very low probabilities of Type 1 errors, and correspondingly high probabilities of Type 2 errors. Group designs are usually interpreted with explicit, moderately low probabilities of Type 1 errors, and therefore with not such high probabilities of Type 2 errors as in the other paradigm. This difference may seem to be a minor one, considered in terms of centiles on a probability scale. However, when it is interpreted in terms of the substantive kinds of results likely to be produced by each paradigm, it appears that the individual‐subject‐design paradigm is more likely to contribute to the development of a technology of behavior, and it is suggested that this orientation should not be abandoned.