Extended abstract
Non-archival submissions of 4–8 pages, excluding Limitations, Appendix, and References.
Machine Learning/CORE Unranked
UserSim NeurIPS 2026
NeurIPS 2026 Workshop on Grounded User Simulation for Model Evaluation and Training: Diversity, Fidelity, and Validity
UserSim @ NeurIPS 2026 is a workshop focused on establishing trustworthy, open, and shared user simulation methods for evaluating and training AI systems. It brings together researchers from diverse fields to address challenges in diversity, fidelity, and validity of simulated users, aiming to build community standards, benchmarks, and tools to ensure simulation results transfer to real-world human behavior.
Key deadlines
Verified August 30, 2026Full paper
September 2, 2026
AoE
Workshop timeline
Submission and decisions
Full paperKey deadline
September 2, 2026 · AoE
Paper fit
Contribution paths
A strong submission should clearly identify its contribution and evaluate it appropriately.
Short paper
Non-archival submissions of 4–8 pages, excluding Limitations, Appendix, and References.
Research areas in scope
01
Diversity
Population grounding and representativenessFairness and demographic, dialectal, and multilingual calibration of simulatorsScenario and goal generation, including coverage of rare and long-tail interactions
02
Fidelity
Behavioral realism and cognitive plausibility of simulated users; the Sim2Real gap and validation against real humansIndividual- and population-level fidelity, including behavioral variation, style, strategy, and consistency over timeControllability and reliability: steering persona and instruction-following, consistency across runs, and simulator failures that invalidate a measurement or a reward signal
03
Validity
Simulator diversityTrain/eval separation and contaminationHuman calibrationLLM-judge auditing
04
Settings and modalities
Agentic and tool-use user simulation; interactive and trajectory-level evaluationVoice and multimodal user simulation: turn-taking, interruption, and full-duplex interactionConversational search, dialogue systems, recommender systems, HCI, and social simulation
05
Training and infrastructure
Simulation for training: SFT, preference optimization, and process-reward data generation; the user simulator as an interactive RL environmentSmall, open, and distilled user simulators, including specialized models rather than prompted ones, that the community can run locallySynthetic-data generation and compound-AI pipelines for building, grounding, and scaling simulators (frameworks, persona datasets)
Policies worth checking twice
- Submissions must be anonymized for double-blind review
- Paper length is 4–8 pages, excluding Limitations, Appendix, and References
- Previously published work and work appearing in the NeurIPS 2026 main track are not eligible
- Preprints are permitted and not grounds for rejection, but submissions must still be anonymized
- Concurrent submissions are permitted because the workshop is non-archival, provided the other venue’s policies also permit it
- At least one author is expected to present each accepted paper in person
- If no author can attend, the paper will remain accepted and listed but will not receive a poster slot
- Submissions are non-archival; authors retain all rights
Official sources
Compiled from the official call for papers. The organizers’ pages remain authoritative.
Last verified August 30, 2026