Deciding about decision models of remember and know judgments: a reply to Murdock (2006)

B. B. Murdock (2006) has interpreted remember-know data within a decision space defined by item and associative information, the fundamental variables in his general recognition memory model TODAM (B. B. Murdock, 1982). He has related parameters of this extended model to stimulus characteristics for several classic remember-know data sets. The authors show that this accomplishment is shared by both one- and two-dimensional signal-detection-based remember-know models (J. C. Dunn, 2004; C. M. Rotello, N. A. Macmillan, & J. A. Reeder, 2004; J. T. Wixted & V. Stretch, 2004), which can be represented in this same decision space and can be related to stimulus characteristics with similar success. Murdock claims that his model, unlike its competitors, is a process model; however, the process aspects of TODAM are not used in his application, and the decision aspects are identical to a previously proposed model. Murdock's claim that one competing model (STREAK; C. M. Rotello et al., 2004) is not fully specified is shown to be false. The new model is not superior to existing ones, but comparisons among the models to date are not definitive. The authors describe several strategies that might be applied to distinguish among them.