Verbal reports as data.

The central proposal of this article is that verbal reports are data. Accounting for verbal reports, as for other kinds of data, requires explication of the mech-anisms by which the reports are generated, and the ways in which they are sensitive to experimental factors (instructions, tasks, etc.). Within the theoret-ical framework of human information processing, we discuss different types of processes underlying verbalization and present a model of how subjects, in re-sponse to an instruction to think aloud, verbalize information that they are attending to in short-term memory (STM). Verbalizing information is shown to affect cognitive processes only if the instructions require verbalization of information that would not otherwise be attended to. From an analysis of what would be in STM at the time of report, the model predicts what can reliably be reported. The inaccurate reports found by other research are shown to result from requesting information that was never directly heeded, thus forcing subjects to infer rather than remember their mental processes. After a long period of time during which stimulus-response relations were at the focus of attention, research in psychology is now seeking to understand in detail the mecha-nisms and internal structure of cognitive pro-cesses that produce these relations. In the limiting case, we would like to have process models so explicit that they could actually produce the predicted behavior from the in-formation in the stimulus.