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arXiv · 2608.30644

Marginal Coordinate Test for Fr\'echet Regression with Random Objects

Jiaye Chen·Rui Qiu·Roulin Wang·Zhou Yu
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Abstract

We develop a marginal coordinate test for regression with Euclidean predictors and a random-object response in a separable metric space. The goal is to test whether a predictor provides additional information about the response conditional on the remaining predictors. In a semi-supervised design, an unlabeled sample is used to estimate predictor conditional means, while an independent labeled sample is reserved for inference. The resulting residuals are combined with a product-space kernel to form a kernel conditional mean dependence (KCMD) U-statistic without requiring a response residual. The primary identity-based test targets a necessary conditional mean restriction, while a multiple-transformation extension probes broader alternatives. We establish a weighted centered chi-square null limit, wild bootstrap validity, consistency against fixed detectable alternatives, and local power under mean-element alternatives. For simultaneous inference, truncated p-to-e calibration combined with e-BH provides asymptotic false discovery rate control under general dependence. Simulations with Euclidean and non-Euclidean responses, together with a New York City taxi-flow analysis, illustrate the method.

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Jiaye Chen, Rui Qiu, Roulin Wang, Zhou Yu. 2026-08-31. Marginal Coordinate Test for Fr\'echet Regression with Random Objects. https://arxiv.org/abs/2608.30644

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