Abstract:
:The percentile-finding experimental design known variously as 'forced-choice fixed-staircase', 'geometric up-and-down' or 'k-in-a-row' (KR) was introduced by Wetherill four decades ago. To date, KR has been by far the most widely used up-and-down (U&D) design for estimating non-median percentiles; it is implemented most commonly in sensory studies. However, its statistical properties have not been fully documented, and the existence of a unique mode in its asymptotic treatment distribution has been recently disputed.Here we revisit the KR design and its basic properties. We find that KR does generate a unique stationary mode near its target percentile, and also displays better operational characteristics than two other U&D designs that have been studied more extensively. Supporting proofs and numerical calculations are presented. A recent experimental example from anesthesiology serves to highlight some of the 'up-and-down' design family's properties and advantages.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Oron AP,Hoff PDdoi
10.1002/sim.3590subject
Has Abstractpub_date
2009-06-15 00:00:00pages
1805-20issue
13eissn
0277-6715issn
1097-0258journal_volume
28pub_type
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