The robustness and applicability of speed–accuracy decomposition, a technique for measuring partial information.

Abstract

Speed-accuracy decomposition (SAD) is a relatively new technique for studying the time course of information processing. It uses information on both the temporal distributions and the accuracies of participants' responses to two types of trials to derive an estimate of the amount of partial information available to participants at specific points in processing. As a new technique, its range of applicability and robustness have not yet been fully determined. Simulations are reported here that investigate these issues, with simulated data sets, SAD analysis of same, and comparison of the SAD analysis results to the parameters used to generate the data.In general, SAD appears to be reasonably robust against certain violations of assumptions and a variety of unusual data patterns. It is recommended that future SAD studies be accompanied by simulations based on observed parameters to better understand the data obtained. Cognitive psychologists are frequently confronted by the fact that measures of mental functioning are necessarily limited and frequently indirect. Two commonly used measures are response time (RT) and ac-

Combining speed and accuracy to assess error-free cognitive processes

“…First, we assume that the error-free and guessing processes are independent within a trial. Similar assumptions have been made in the class of "speed-accuracy decomposition" models (Meyer, Irwin, Osman, and Kounios, 1988;Smith, Kounios, and Osterhout, 1997). While the criticisms raised about speed-accuracy decomposition may apply to our model, any dependence between the two processes is lessened by the incorporation of covariate information.…”

“…This is the most conceptually satisfactory method for addressing SAT (Luce, 1986), but is labor-intensive and not widely practiced. An alternative method is to give a response signal at some point during a trial, intended to force a decision at that point in time in order to estimate the accumulation of partial information upon which a decision could be based (e.g., Smith, Kounios, and Osterhout, 1997).…”

On the continuity of thought and the representation of knowledge: Electrophysiological and behavioral time-course measures reveal levels of structure in semantic memory

“…Fortunately, Meyer and his associates (Meyer et aI., 1988) developed a technique that sheds light on this issue, which they called "speed-accuracy decomposition" (SAD; see also R. W. Smith, Kounios, & Osterhout, 1996). SAD combines a new experimental procedure and quantitative analysis that enables the experimenter to remove from an SAT function the contribution of trials on which subjects responded from the final state of relatively complete response accuracy.…”

The criterion validity of tasks of basic cognitive processes

“…For example, information processing speed tasks presented in a rigorous experimental paradigm, e.g., choice reaction time, stimulus discrimination time, allow a dissociation between decision time and movement time, which is not possible for less experimental processing speed tests, such as Digit Symbol and Symbol Search in conventional test batteries. Experimental manipulations may also permit a separation of the accuracy component from the speed component in information processing speed tasks (Dosher, 1979;Smith, Kounios, & Osterhout, 1997). For working memory tasks, experimental manipulations are sometimes used to differentiate between the subcomponent of short-term storage and the subcomponent of central executive, and the two subcomponents seem to have disparate relations with intellectual abilities .…”