Saved in:
Bibliographic Details
Main Authors: Kim, Hwanwoo, Zhang, Xin, Zhao, Jiwei, Tian, Qinglong
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2401.16410
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911766910337024
author Kim, Hwanwoo
Zhang, Xin
Zhao, Jiwei
Tian, Qinglong
author_facet Kim, Hwanwoo
Zhang, Xin
Zhao, Jiwei
Tian, Qinglong
contents The presence of distribution shifts poses a significant challenge for deploying modern machine learning models in real-world applications. This work focuses on the target shift problem in a regression setting (Zhang et al., 2013; Nguyen et al., 2016). More specifically, the target variable y (also known as the response variable), which is continuous, has different marginal distributions in the training source and testing domain, while the conditional distribution of features x given y remains the same. While most literature focuses on classification tasks with finite target space, the regression problem has an infinite dimensional target space, which makes many of the existing methods inapplicable. In this work, we show that the continuous target shift problem can be addressed by estimating the importance weight function from an ill-posed integral equation. We propose a nonparametric regularized approach named ReTaSA to solve the ill-posed integral equation and provide theoretical justification for the estimated importance weight function. The effectiveness of the proposed method has been demonstrated with extensive numerical studies on synthetic and real-world datasets.
format Preprint
id arxiv_https___arxiv_org_abs_2401_16410
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle ReTaSA: A Nonparametric Functional Estimation Approach for Addressing Continuous Target Shift
Kim, Hwanwoo
Zhang, Xin
Zhao, Jiwei
Tian, Qinglong
Machine Learning
The presence of distribution shifts poses a significant challenge for deploying modern machine learning models in real-world applications. This work focuses on the target shift problem in a regression setting (Zhang et al., 2013; Nguyen et al., 2016). More specifically, the target variable y (also known as the response variable), which is continuous, has different marginal distributions in the training source and testing domain, while the conditional distribution of features x given y remains the same. While most literature focuses on classification tasks with finite target space, the regression problem has an infinite dimensional target space, which makes many of the existing methods inapplicable. In this work, we show that the continuous target shift problem can be addressed by estimating the importance weight function from an ill-posed integral equation. We propose a nonparametric regularized approach named ReTaSA to solve the ill-posed integral equation and provide theoretical justification for the estimated importance weight function. The effectiveness of the proposed method has been demonstrated with extensive numerical studies on synthetic and real-world datasets.
title ReTaSA: A Nonparametric Functional Estimation Approach for Addressing Continuous Target Shift
topic Machine Learning
url https://arxiv.org/abs/2401.16410