分析高频时间序列反应的实验,以及对功率和样本大小的影响
Brian Rafor1, Iris Ivy Gauran2, Hernando Ombao2
1School of Statistics, University of the Philippines, Diliman, Quezon City, 1101, Philippines.
Scientific reports
|May 14, 2025
概括
高频时间序列数据的统计方法对于医学研究中准确的样本大小确定和功率分析至关重要. 动态时间扭曲和时间序列聚类为分析复杂的医学成像数据提供了强大的解决方案.
科学领域:
- 统计推断的统计推断.
- 生物统计学 生物统计学
- 医学成像分析分析 医学成像分析
背景情况:
- 实验数据越来越多地呈现为高维,高频的时间序列.
- 由于复杂的数据结构,时间滞后和相位移,统计推理在样本大小确定和功率分析方面面临挑战.
- 医学成像数据中的非统一,正常过程进一步混了分析.
研究的目的:
- 解决在案例控制研究中对高频时间序列数据的样本大小确定和功率分析方面的挑战.
- 引入一种使用时间序列聚类和动态时间扭曲来分析医学成像数据的新方法.
- 在临床研究中,提供一个优化统计能力的策略,采用最小的样本大小.
主要方法:
- 利用基于动态时间扭曲的时间序列聚类来分析实验反应.
- 员工动态时间扭曲,以实现灵活的距离测量,可靠的时间点竞争.
- 开发了内核回归来链接样本大小,效果大小和统计能力,考虑时间序列数据结构.
主要成果:
- 时间序列聚类成功地分割了实验单元,并启用了效果大小计算.
- 拟议的方法证明了在模拟数据和ADHD-200 fMRI数据集中区分病例和对照组的能力.
- 测量时间序列组之间的距离被证明对确定目标功率的样本大小是有效的.
结论:
- 时间序列聚类为传统方法提供了可行的替代方案,例如对高频时间序列数据的方差分析.
- 开发的核心回归框架为临床医生提供了一种实用的策略,以优化功率和样本大小.
- 这种方法提高了分析复杂的时间序列医疗数据的统计严谨性,提高了临床研究的效率.
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