Saved in:
Bibliographic Details
Main Authors: Turbal, Bohdan, Voitsitska, Iryna, Semenova, Lesia
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2602.07674
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908819697696768
author Turbal, Bohdan
Voitsitska, Iryna
Semenova, Lesia
author_facet Turbal, Bohdan
Voitsitska, Iryna
Semenova, Lesia
contents Machine learning models now influence decisions that directly affect people's lives, making it important to understand not only their predictions, but also how individuals could act to obtain better results. Algorithmic recourse provides actionable input modifications to achieve more favorable outcomes, typically relying on counterfactual explanations to suggest such changes. However, when the Rashomon set - the set of near-optimal models - is large, standard counterfactual explanations can become unreliable, as a recourse action valid for one model may fail under another. We introduce ElliCE, a novel framework for robust algorithmic recourse that optimizes counterfactuals over an ellipsoidal approximation of the Rashomon set. The resulting explanations are provably valid over this ellipsoid, with theoretical guarantees on uniqueness, stability, and alignment with key feature directions. Empirically, ElliCE generates counterfactuals that are not only more robust but also more flexible, adapting to user-specified feature constraints while being substantially faster than existing baselines. This provides a principled and practical solution for reliable recourse under model uncertainty, ensuring stable recommendations for users even as models evolve.
format Preprint
id arxiv_https___arxiv_org_abs_2602_07674
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle ElliCE: Efficient and Provably Robust Algorithmic Recourse via the Rashomon Sets
Turbal, Bohdan
Voitsitska, Iryna
Semenova, Lesia
Machine Learning
Machine learning models now influence decisions that directly affect people's lives, making it important to understand not only their predictions, but also how individuals could act to obtain better results. Algorithmic recourse provides actionable input modifications to achieve more favorable outcomes, typically relying on counterfactual explanations to suggest such changes. However, when the Rashomon set - the set of near-optimal models - is large, standard counterfactual explanations can become unreliable, as a recourse action valid for one model may fail under another. We introduce ElliCE, a novel framework for robust algorithmic recourse that optimizes counterfactuals over an ellipsoidal approximation of the Rashomon set. The resulting explanations are provably valid over this ellipsoid, with theoretical guarantees on uniqueness, stability, and alignment with key feature directions. Empirically, ElliCE generates counterfactuals that are not only more robust but also more flexible, adapting to user-specified feature constraints while being substantially faster than existing baselines. This provides a principled and practical solution for reliable recourse under model uncertainty, ensuring stable recommendations for users even as models evolve.
title ElliCE: Efficient and Provably Robust Algorithmic Recourse via the Rashomon Sets
topic Machine Learning
url https://arxiv.org/abs/2602.07674