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arXiv · 2605.12200

Investigating simple target-covariate relationships for Chronos-2 and TabPFN-TS

Gaspard Berthelier·Mariia Baranova·Andrei-Tiberiu Pantea·Etienne Le Naour·Adrien Petralia·Tahar Nabil·Themis Palpanas
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Abstract

Time Series Foundation Models (TSFMs) have recently achieved state-of-the-art performance, often outperforming supervised models in zero-shot settings. Recent TSFM architectures, such as Chronos-2 and TabPFN-TS, aim to integrate covariates. In this paper, we design controlled experiments based on simple target-covariate relationships to assess this integration capability. Our results show that TabPFN-TS captures these relationships more effectively than Chronos-2, especially for short horizons, suggesting that the strong benchmark performance of Chronos-2 does not automatically translate into optimal modeling of simple covariate-target dependencies.

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Gaspard Berthelier, Mariia Baranova, Andrei-Tiberiu Pantea, Etienne Le Naour, Adrien Petralia, Tahar Nabil, Themis Palpanas. 2026-05-12. Investigating simple target-covariate relationships for Chronos-2 and TabPFN-TS. https://arxiv.org/abs/2605.12200

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