Confidence Lexicon: Effects on the Confidence-Accuracy Relationship

We compared an evidence-based lexicon to numeric and verbal methods for obtaining confidence in a lineup decision. Participants watched two videos (one target each) and, following a delay, made a lineup decision for each target. Confidence was provided after each lineup decision using the lexicon (numeric, verbal, and visual), verbally (own words, then on a slider from “not at all confident” to “completely confident”), or numerically (0-100% scale). CAC curves indicate no difference between the approaches. An empirically-derived confidence lexicon performs as well as extant methods of collecting confidence but may reduce miscommunications common in practice (using a verbal approach).