http://repub.eur.nl/res/aut/1499/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/1005/ 2003-01-01T00:00:00Z We present a new model for lexical decision, REM-LD, that is based on REM theory (e.g., Shiffrin & Steyvers, 1997). REM-LD uses a principled (i.e., 'Bayes' rule) decision process that simultaneously considers the diagnosticity of the evidence for the 'WORD' response and the 'NONWORD' response. The model calculates the odds ratio that the presented stimulus is a word or a nonword by accumulating likelihood ratios for each lexical entry in a small neighborhood of similar words. We report two experiments that used the signal-to-respond paradigm to obtain information about the time course of lexical processing. Experiment 1 verified the prediction of the model that the frequency of the word stimuli affects performance for nonword stimuli. Experiment 2 was done to study the effects of nonword lexicality, word frequency, and repetition priming and to demonstrate how REM-LD can account for the observed results. We discuss how REM-LD can be extended to account for effects of phonology such as the pseudohomophone effect, and how REM-LD can predict response times in the popular 'respond-when-ready' paradigm. Several other quantitative models of lexical decision are evaluated with respect to the findings reported here. http://repub.eur.nl/res/pub/1009/ 2003-01-01T00:00:00Z The REM model originally developed for recognition memory (Shiffrin & Steyvers, 1997) has recently been extended to implicit memory phenomena observed during threshold identification of words. We discuss two REM models based on Bayesian principles: a model for long-term priming (REMI; Schooler, Shiffrin, & Raaijmakers, 1999), and a model for short-term priming (ROUSE; Huber, Shiffrin, Lyle, & Ruys, in press). Although the identification tasks are the same, the basis for priming differs in the two models. In both paradigms we ask whether prior study merely reflects a bias to interpret ambiguous information in a certain manner, or instead leads to more efficient encoding. The observation of a ‘both-primed benefit’ in two-alternative forced-choice paradigms appears to show that both processes are present. However, the REMI model illustrates that the both-primed benefit is not necessarily indicative of an increase in perceptual sensitivity but might be generated by a criterion bias. The ROUSE model demonstrates how the amount of attention paid to the prime, and the consequent effect upon decision making, may lead to the reversal of the normal short-term priming effect that is observed in certain conditions.