One-up-two-down adaptive staircases can report lower thresholds than other estimation methods

Evidence

An adaptive three-interval, three-alternative forced-choice (3-AFC) discrimination procedure, coupled with a one-up-two-down staircase rule tracking the 70.7 %-correct point on the underlying psychometric function, was used. … On average, this method provides a threshold value, which is lower than that produced by e.g. Levitt ( 1971 ) or Neher et al. ( 2011 ). … Further, since this study investigates differences between conditions (cues) rather than the absolute MAA values, the consequently lower MAA was accepted. — Dijk, Pim van, Physiology, Psychoacoustics and…, 3061

Categorization

• DEFINE: Defines the one-up-two-down staircase and notes its bias toward lower thresholds versus Levitt and Neher methods.
• QUESTION: Why does the one-up-two-down approach bias thresholds downward? Worth checking the psychometric/estimator mechanism.
• corroborated: 2 independent passages support this claim — Dijk, Pim van, Physiology, Psychoacoustics and…, 3061