不确定性限制了功率分析的使用
Jolynn Pek1, Mark A Pitt1, Duane T Wegener1
1Department of Psychology, The Ohio State University.
Journal of experimental psychology. General
|April 8, 2024
概括
实验设计的统计功率计算可能具有误导性. 对效应大小估计的不确定性和对人口效应大小的随机波动使得功率值无法用于证明样本大小的可靠性.
科学领域:
- 统计 统计 统计 统计
- 实验设计 实验设计
- 心理学 心理学 心理学
背景情况:
- 在实验设计中,统计能力通常用于证明样本大小的合理性.
- 经典的功率计算往往忽略了关键的不确定性来源.
- 这可能会导致在设计选择中产生错误的精确感.
研究的目的:
- 调查不确定性对统计功率计算的影响.
- 为了证明将采样变化和人口效应大小波动纳入的后果.
- 评估基于功率的样本大小证明的可靠性.
主要方法:
- 利用模拟研究来模拟不确定性的影响.
- 在估计效应大小 (科恩d) 中纳入采样变异性.
- 在人口效应大小中引入随机波动.
主要成果:
- 在效果大小估计中的采样变异性引入了对功率和样本大小确定性的重大不确定性.
- 人口效应大小的随机波动可以使计算的功率值变得毫无意义.
- 模拟显示,计算的功率值可能是高度不稳定的和误导性的.
结论:
- 研究人员应对基于功率的样本大小证明给予最低限度的信任.
- 忽略不确定性的经典功率计算提供了一个错误的精度感.
- 建议重新考虑对实验设计的传统功率分析的依赖.
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