Wasserstein-regularized Conformal Prediction under General Distribution Shift

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Xu, Rui, Chen, Chao, Sun, Yue, Venkitasubramaniam, Parvathinathan, Xie, Sihong
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866913721387843584
author Xu, Rui
Chen, Chao
Sun, Yue
Venkitasubramaniam, Parvathinathan
Xie, Sihong
author_facet Xu, Rui
Chen, Chao
Sun, Yue
Venkitasubramaniam, Parvathinathan
Xie, Sihong
contents Conformal prediction yields a prediction set with guaranteed $1-α$ coverage of the true target under the i.i.d. assumption, which may not hold and lead to a gap between $1-α$ and the actual coverage. Prior studies bound the gap using total variation distance, which cannot identify the gap changes under distribution shift at a given $α$. Besides, existing methods are mostly limited to covariate shift,while general joint distribution shifts are more common in practice but less researched.In response, we first propose a Wasserstein distance-based upper bound of the coverage gap and analyze the bound using probability measure pushforwards between the shifted joint data and conformal score distributions, enabling a separation of the effect of covariate and concept shifts over the coverage gap. We exploit the separation to design an algorithm based on importance weighting and regularized representation learning (WR-CP) to reduce the Wasserstein bound with a finite-sample error bound.WR-CP achieves a controllable balance between conformal prediction accuracy and efficiency. Experiments on six datasets prove that WR-CP can reduce coverage gaps to $3.2\%$ across different confidence levels and outputs prediction sets 37$\%$ smaller than the worst-case approach on average.
format Preprint
id arxiv_https___arxiv_org_abs_2501_13430
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Wasserstein-regularized Conformal Prediction under General Distribution Shift
Xu, Rui
Chen, Chao
Sun, Yue
Venkitasubramaniam, Parvathinathan
Xie, Sihong
Machine Learning
Conformal prediction yields a prediction set with guaranteed $1-α$ coverage of the true target under the i.i.d. assumption, which may not hold and lead to a gap between $1-α$ and the actual coverage. Prior studies bound the gap using total variation distance, which cannot identify the gap changes under distribution shift at a given $α$. Besides, existing methods are mostly limited to covariate shift,while general joint distribution shifts are more common in practice but less researched.In response, we first propose a Wasserstein distance-based upper bound of the coverage gap and analyze the bound using probability measure pushforwards between the shifted joint data and conformal score distributions, enabling a separation of the effect of covariate and concept shifts over the coverage gap. We exploit the separation to design an algorithm based on importance weighting and regularized representation learning (WR-CP) to reduce the Wasserstein bound with a finite-sample error bound.WR-CP achieves a controllable balance between conformal prediction accuracy and efficiency. Experiments on six datasets prove that WR-CP can reduce coverage gaps to $3.2\%$ across different confidence levels and outputs prediction sets 37$\%$ smaller than the worst-case approach on average.
title Wasserstein-regularized Conformal Prediction under General Distribution Shift
topic Machine Learning
url https://arxiv.org/abs/2501.13430