UserSimCRS v2: Simulation-Based Evaluation for Conversational Recommender Systems

Nolwenn Bernard; Krisztian Balog

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arXiv · 2512.04588

UserSimCRS v2: Simulation-Based Evaluation for Conversational Recommender Systems

Nolwenn Bernard·Krisztian Balog

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Abstract

Resources for simulation-based evaluation of conversational recommender systems (CRSs) are scarce. The UserSimCRS toolkit was introduced to address this gap. In this work, we present UserSimCRS v2, a significant upgrade aligning the toolkit with state-of-the-art research. Key extensions include an enhanced agenda-based user simulator, introduction of large language model-based simulators, integration for a wider range of CRSs and datasets, and new LLM-as-a-judge evaluation utilities. We demonstrate these extensions in a case study.

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BibTeX RIS

Nolwenn Bernard, Krisztian Balog. 2025-12-04. UserSimCRS v2: Simulation-Based Evaluation for Conversational Recommender Systems. https://arxiv.org/abs/2512.04588

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