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arXiv 2406.03346cs.LGmath.PRstat.ML
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用于保形回归的归一化流

Normalizing Flows for Conformal Regression

Royal Holloway, University of London(伦敦大学皇家霍洛威学院)

Nicolo Colombo

AI总结:

本文提出通过训练归一化流学习优化距离度量,以局部化保形预测区间,提高效率,并兼容现有自适应策略。

摘要:

保形预测(CP)算法通过在标记数据上校准预测模型的输出来估计其不确定性。相同的校准方案通常适用于任何模型和数据,无需修改。所获得的预测区间在构造上是有效的,但如果预测误差在输入空间上分布不均匀,则可能效率低下,即不必要地大。我们提出了一种通用方案,通过训练校准过程来局部化区间。标准预测误差被替换为一种优化的距离度量,该度量显式依赖于对象属性。学习最优度量等价于训练一个作用于误差和输入联合分布的归一化流。与Papadopoulos等人(2008)的误差重新加权CP算法不同,该框架允许估计名义条件有效性与经验条件有效性之间的差距。该方法与现有的基于重新加权校准样本的局部自适应CP策略兼容,并适用于任何无需重新训练的点预测模型。

英文摘要:

Conformal Prediction (CP) algorithms estimate the uncertainty of a prediction model by calibrating its outputs on labeled data. The same calibration scheme usually applies to any model and data without modifications. The obtained prediction intervals are valid by construction but could be inefficient, i.e. unnecessarily big, if the prediction errors are not uniformly distributed over the input space. We present a general scheme to localize the intervals by training the calibration process. The standard prediction error is replaced by an optimized distance metric that depends explicitly on the object attributes. Learning the optimal metric is equivalent to training a Normalizing Flow that acts on the joint distribution of the errors and the inputs. Unlike the Error Reweighting CP algorithm of Papadopoulos et al. (2008), the framework allows estimating the gap between nominal and empirical conditional validity. The approach is compatible with existing locally-adaptive CP strategies based on re-weighting the calibration samples and applies to any point-prediction model without retraining.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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