走向更可靠的QSAR:关于数据集分区的系统讨论
1School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
Journal of chemical information and modeling
|February 2, 2026
概括
数据分割方法和随机种子显著影响QSAR模型的概括性. 仔细选择测试集对于可靠的模型评估至关重要,避免膨胀的性能指标.
科学领域:
- 定量结构-活动关系 (QSAR) 建模.
- 化学信息学 化学信息学
- 计算化学计算化学
背景情况:
- QSAR模型的开发正在迅速增加.
- 有关QSAR模型评估的严格性存在担忧,特别是关于数据分割策略的担忧.
- 数据分区对模型通用性的影响需要系统研究.
研究的目的:
- 系统地评估随机分割 (RS),基于相似性的分割 (SS) 和随机种子变异性对QSAR模型概括性的影响.
- 在有限数据 (化学查) 和充足数据 (标准建模) 的场景下评估这些效应.
- 挑战合理分割优化内部性能普遍提高模型性能的假设.
主要方法:
- 利用了五个不同大小的数据集.
- 对比随机分割 (RS) 和基于相似性的分割 (SS).
- 研究了随机种子变异性对模型性能的影响.
主要成果:
- 数据分区方法和随机种子选择都会大大影响内部测试性能,可能会误解真正的预测能力.
- 基于相似性的分割 (SS) 可能会提高内部性能,但并不总是提高外部通用性.
- 在较低的采样比率下,SS可以在内部和外部测试中低于随机分割 (RS) 的性能.
- 在最小数据集上的内部测试中,在随机种子中观察到R平方的高变化,与固定外部数据集的较低变化形成鲜明对比.
- 适用性域 (AD) 过没有持续减少外部数据集的变化.
结论:
- 测试组的构建必须与QSAR模型的现实应用场景保持一致.
- 研究人员应避免单个或桃挑选的随机种子和不合适的合理分区方法.
- 透明的,与应用程序一致的分区协议和AD方法对于优先考虑真正的外部通用性而不是潜在的膨胀内部指标至关重要.
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