The effects of target discriminability and criterion placement on accuracy rates in sequential and simultaneous target-present lineups

Participants attempted to select previously studied faces from lineups that were administered either sequentially (test faces presented one at a time) or simultaneously (test faces presented altogether). Target discriminability was manipulated by varying the number of facial features that could be used to distinguish the study face from the other test faces (foils) or by varying study face exposure duration. In addition, decision criterion level was manipulated via an instruction manipulation. Results indicated that sequential participants adopted a stricter decision standard under high criterion instructions compared to simultaneous participants. Under liberal criterion setting instructions, the rate at which the target was selected was comparable across lineup procedures. Target discriminability affected target selections to a greater extent in simultaneous compared to sequential lineups. We discuss the applied implications that these findings have regarding correct identifications from lineups.