Behavior Research Methods

, Volume 39, Issue 2, pp 291–302 | Cite as

Testing the race model inequality: An algorithm and computer programs

  • Rolf UlrichEmail author
  • Jeff MillerEmail author
  • Hannes SchröterEmail author


In divided-attention tasks, responses are faster when two target stimuli are presented, and thus one is redundant, than when only a single target stimulus is presented. Raab (1962) suggested an account of this redundanttargets effect in terms of a race model in which the response to redundant target stimuli is initiated by the faster of two separate target detection processes. Such models make a prediction about the probability distributions of reaction times that is often calledthe race model inequality, and it is often of interest to test this prediction. In this article, we describe a precise algorithm that can be used to test the race model inequality and present MATLAB routines and a Pascal program that implement this algorithm.


Stimulus Condition Race Model Reaction Time Distribution Redundancy Gain Specific Software Requirement 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Psychonomic Society, Inc. 2007

Authors and Affiliations

  1. 1.Abteilung für Allgemeine & Biologische Psychologie, Psychologisches InstitutUniversität TübingenTübingenGermany
  2. 2.Department of PsychologyUniversity of OtagoDunedinNew Zealand

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