Understanding child abuse: Edited by David N. Jones. Hodder & Stoughton, Sevenoaks, Kent. 1982. 299 pp. £2.95.

Abstract

The ABX discrimination task is a discrimination test in which the two test samples, A and B (one of which is the control sample, the other a modified sample), are presented to the participant first followed by sample X. The participant has to decide which sample X most closely represents (A or B). Results are tallied and dʹ values are calculated to determine if a significant difference exists between the samples. The ABX discrimination task may be thought of as a duo-trio test in reverse: in a duo-trio test, the reference sample is presented first, then the assessor has to decide which of two samples matches the reference; in the ABX test the assessor is given the two test samples first, then they are asked to match the final sample to A or B.The ABX discrimination task is most commonly used in psycholinguistics and acoustic testing although it is occasionally used in sensory science and has potential to become more widely used in particular because of the advantage that participants get to experience the two different products (A and B) before deciding which sample product X most closely represents.