Skip to main content
Revisiting absolute and relative judgments in the WITNESS model
Psychonomic Bulletin & Review (2014)
  • Dr. Dustin A. Fife, Rowan University
  • Colton J. Perry
  • Scott D. Gronlund
The WITNESS model (Clark in Applied Cognitive Psychology 17:629–654, 2003) provides a theoretical framework with which to investigate the factors that contribute to eyewitness identification decisions. One key factor involves the contributions of absolute versus relative judgments. An absolute contribution is determined by the degree of match between an individual lineup member and memory for the perpetrator; a relative contribution involves the degree to which the best-matching lineup member is a better match to memory than the remaining lineup members. In WITNESS, the proportional contributions of relative versus absolute judgments are governed by the values of the decision weight parameters. We conducted an exploration of the WITNESS model’s parameter space to determine the identifiability of these relative/absolute decision weight parameters, and compared the results to a restricted version of the model that does not vary the decision weight parameters. This exploration revealed that the decision weights in WITNESS are difficult to identify: Data often can be fit equally well by setting the decision weights to nearly any value and compensating with a criterion adjustment. Clark, Erickson, and Breneman (Law and Human Behavior 35:364–380,2011) claimed to demonstrate a theoretical basis for the superiority of lineup decisions that are based on absolute contributions, but the relationship between the decision weights and the criterion weakens this claim. These findings necessitate reconsidering the role of the relative/absolute judgment distinction in eyewitness decision making.
  • Computational modeling,
  • WITNESS model,
  • Eyewitness identification,
  • Relative and absolute judgements
Publication Date
April, 2014
Citation Information
Dustin A. Fife, Colton J. Perry and Scott D. Gronlund. "Revisiting absolute and relative judgments in the WITNESS model" Psychonomic Bulletin & Review Vol. 21 Iss. 2 (2014) p. 479 - 487
Available at: