Recognition is the cognitive process by which we judge whether a given object, person, place, or event has occurred in our previous experience or is new to us. According to signal detection theory, old/new recognition decisions are based on how much evidence one finds in memory that an item has appeared previously (e.g., its familiarity) but can be affected substantially by response bias, a general proclivity to respond “old” or “new.” When experimental conditions evoke a “conservative” response bias, participants will require a relatively high amount of memory evidence before calling an item “old” and will give a high proportion of “new” responses to both old and new items; when conditions promote a “liberal” bias, participants will relax their required level of memory evidence and will call a high proportion of both old and new items “old.” Response bias is usually analyzed at a group level, but substantial individual differences in bias can underlie group means. These differences suggest that, independent of any experimental manipulation, some people require more memory evidence than others before they are willing to call an item “old.” The central motivation for the present work is the possibility that these individual differences are meaningful and reflect bias levels that inhere within individuals. Seven experiments were designed to test the hypothesis that response bias can be characterized as an intra-individually stable cognitive “trait” with an influence extending beyond recognition memory. The present experiments are based on the expectation that if response bias is a cognitive trait, it should a) be consistent within an individual across time, to-be-recognized materials, and situations; b) generalize beyond recognition memory to other tasks involving binary decisions based on accumulated evidence; c) be associated with personality traits that represent one’s willingness to take action based on limited information; and d) carry consequences for recognition in applied settings. The results indicated substantial within-individual bias consistency in two recognition tests separated by 10 minutes (Experiment 1) and a similar level of consistency when the two tests were separated by one week (Experiment 2). Bias was strongly correlated across the stimulus domains of words and paintings (Experiment 3) and words and faces (Experiment 7). Correlations remained significant across two ostensibly independent experiments differing markedly in context and materials and separated by an average of 2.5 weeks (Experiments 6 and 7). Recognition bias predicted frequency of false recall in the Deese-Roediger-McDermott (DRM) paradigm (Experiment 4) and false alarms in an eyewitness identification task (Experiment 7). No relationship was detected between bias and grain size in estimation from general knowledge (Experiment 2), risk avoidance through the use of report option on a trivia task (Experiments 4 and 5), or speed and accuracy on a go-no go task (Experiment 6). Personality measures suggested relationships between response bias and need for cognition, maximizing versus satisficing tendencies, and regret proneness. Collectively, these findings support the idea that response bias as measured in recognition memory tasks is a partial function of stable individual differences that have broad significance for cognition. / Graduate