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One-tailed tests: Let's do this (responsibly)
1Department of Psychology, University of Mississippi.
Psychological Methods
|November 2, 2023
Summary
Preregistered one-tailed tests offer greater statistical power without increasing false positives, making them valuable for psychological research. Encouraging their use can improve hypothesis testing and research persuasiveness.
Area of Science:
- Psychology
- Statistical Methods
Background:
- One-tailed tests are underutilized in psychology despite controlling false positives.
- Preregistration is key to the valid application of one-tailed tests.
Purpose of the Study:
- Advocate for the use of preregistered one-tailed tests in psychological research.
- Address common misconceptions hindering the adoption of one-tailed tests.
Main Methods:
- Argumentative, based on statistical principles and research best practices.
- Focuses on the benefits of preregistered one-tailed tests.
Main Results:
- Preregistered one-tailed tests maintain false-positive control.
- They offer increased statistical power when the effect direction is correctly predicted.
- These tests align theory with hypothesis and enhance result persuasiveness.
Conclusions:
- One-tailed tests are suitable for applied research, replications, and situations with predictable effects.
- Encouraging preregistered one-tailed tests can improve statistical practices in psychology.
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