Retrieval from memory and cue complexity both trigger exemplar-based processes in judgment

Judgments and decisions can be achieved by a rule-based integration of cues or by retrieving similar exemplars from memory. In judgments based on currently available object descriptions (on-line judgments), people tend to rely on rules unless the cue-criterion relations are difficult to extract. In memory-based decisions, more evidence for exemplarbased reasoning has been found, but hitherto restricted to conditions with unknown cue polarity. These conclusions are threatened by methodological confounds concerning materials, training regime, and type of judgment task. In a factorial experiment, memory-based vs. on-line judgments as well as obvious vs. unknown cue polarity conditions were pitted against each other. Participants judged disease severity based on symptoms. Using the measurement model RulEx-J, we confirmed that both memory retrieval and unknown cue polarity have additive effects on the use of exemplar-based processes. This corroborates the idea that exemplar-based strategies are used as a backup if cue abstraction is unfeasible.