collaborators

5 papers

cs.HC2026

Engagement Phenotypes for a Sample of 102,684 AI Mental Health Chatbot Users and Dose-Response Associations with Clinical Outcomes

Emma C. Wolfe, Ting Su, Olivier Tieleman +3

Background: Conversational AI chatbots are emerging as scalable mental health tools, but little is known about real world engagement or its relationship to clinical outcomes. Objec…

cs.CL2026

Fine-tuning LLMs for Passive Depression Severity Estimation from AI Mental Health Dialogue

Olivier Tieleman, Ziyi Zhu, Ting Su +3

Depression is the leading cause of disability worldwide, and early detection of symptom change is essential for timely intervention. Validated instruments such as the Patient Healt…

cs.CL2026

DIAL: Direct Iterative Adversarial Learning for Realistic Multi-Turn Dialogue Simulation

Ziyi Zhu, Olivier Tieleman, Caitlin A. Stamatis +5

Realistic user simulation is crucial for training and evaluating multi-turn dialogue systems, yet creating simulators that accurately replicate human behavior remains a significant…

cs.CL2026

CyclicJudge: Mitigating Judge Bias Efficiently in LLM-based Evaluation

Ziyi Zhu, Olivier Tieleman, Alexey Bukhtiyarov +1

LLM-as-judge evaluation has become standard practice for open-ended model assessment; however, judges exhibit systematic biases that cannot be averaged out by increasing the number…

cs.CY2026

Beyond Simulations: What 20,000 Real Conversations Reveal About Mental Health AI Safety

Caitlin A. Stamatis, Jonah Meyerhoff, Richard Zhang +3

Mental-health AI safety is typically evaluated with small, simulation-based benchmarks that may not reflect the linguistic and contextual diversity of deployment. We pair four benc…