Cumulative Record. Chapter 8: The Analysis of Behavior. Quote 13

. . . frequency of response provides a continuous account of many basic processes. We can follow a curve of extinction, for example, for many hours, and the conditions of the response at every moment is apparent in our records. This is in marked contrast to methods and techniques which merely sample a learning process from time to time, where the whole process must be inferred. (p. 105)