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Square-root formula for choice reaction time
1Department of Mechanical Engineering, University of Minnesota, Minneapolis 55455-0111, USA.
Perceptual and Motor Skills
|October 1, 1996
Summary
The power law of choice reaction time is discussed, showing the Hick-Hyman law as a special case. A square-root formula offers a concise way to predict reaction time for up to 10 choices.
Area of Science:
- Cognitive Psychology
- Human Factors Engineering
Background:
- Choice reaction time (CRT) is a fundamental measure in cognitive psychology.
- The relationship between the number of stimulus-response alternatives and CRT has been extensively studied.
- Existing models, like the Hick-Hyman law, describe this relationship but may have limitations.
Purpose of the Study:
- To further discuss and analyze the power law of choice reaction time.
- To demonstrate that the Hick-Hyman law is a specific instance of the broader power law.
- To propose and evaluate a square-root function as a more concise predictive model for CRT.
Main Methods:
- Review and theoretical analysis of the power law of choice reaction time.
- Comparison of the power law with the Hick-Hyman law.
- Evaluation of a square-root model for predicting reaction time across varying numbers of stimulus-response pairs.
Main Results:
- The Hick-Hyman law is identified as a special case of the power law of choice reaction time.
- A particular square-root function is proposed as a highly accurate and simple formula.
- The square-root model effectively predicts reaction time for 1 to 10 equiprobable stimulus-response pairs.
Conclusions:
- The power law provides a comprehensive framework for understanding choice reaction time.
- A square-root power law offers a parsimonious and effective model for predicting CRT in common experimental ranges.
- Further theoretical exploration of this model is warranted.
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