Some Practical Guidelines for Effective Sample Size Determination

2001/08/01 by Russell V Lenth, Russell V. Lenth · 1,138 citations
Decision Sciences · Engineering · Mathematics · Psychology · #Advanced Statistical Process Monitoring #Computer science #Engineering #Management science #Mathematics #Meta-analysis and systematic reviews #Psychology #Quality (philosophy) #Sample (material) #Sample size determination #Social psychology #Statistical Methods in Clinical Trials #Statistical power #Statistics #Temptation

paper · doi:10.1198/000313001317098149

published in The American Statistician 55(3), 187-193 (Taylor & Francis)

openalex publication_date 2001/08/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29

Abstract

Sample size determination is often an important step in planning a statistical study—and it is usually a difficult one. Among the important hurdles to be surpassed, one must obtain an estimate of one or more error variances and specify an effect size of importance. There is the temptation to take some shortcuts. This article offers some suggestions for successful and meaningful sample size determination. Also discussed is the possibility that sample size may not be the main issue, that the real goal is to design a high-quality study. Finally, criticism is made of some ill-advised shortcuts relating to power and sample size.

Citations

• The Abuse of Power

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