activity
20242026
most citedEstimating the Hallucination Rate of Generative AI

4 citations · 5 across the 8 of their papers we have counts for

collaborators

11 papers

cs.CV2026

FeaTok: Feature-Loss Tokenization for Image Generation

Zhang Xiaofeng, Samuel Lavoie, Nicolas Beltran-Velez +6

Discrete image generators learn the distribution of tokens produced by an image tokenizer. These token representations should be easy for generators to model, not merely enable fai…

cs.LG2026

Global Exponential Convergence of Two-Layer Linear Network Training

Stephen Y Zhang, Gabriel Peyré

We prove global exponential (linear) convergence with an explicit rate in the rich scaling for wide two-layer linear networks trained with smooth Polyak-Lojasiewicz predictor losse…

cs.LG2026

The Reward Was in Your Data All Along: Correcting Flow Matching with Discriminator-Guided RL

Nicolas Beltran-Velez, Felix Friedrich, Zhang Xiaofeng +4

Score- and flow-matching models often rely on preference-based reinforcement learning for two purposes: aligning with subjective preferences and, surprisingly, recovering propertie…

cs.CV2026

Inference-time Physics Alignment of Video Generative Models with Latent World Models

Jianhao Yuan, Xiaofeng Zhang, Felix Friedrich +7

State-of-the-art video generative models produce promising visual content yet often violate basic physics principles, limiting their utility. While some attribute this deficiency t…

cs.LG2026

Duel-Evolve: Reward-Free Test-Time Scaling via LLM Self-Preferences

Sweta Karlekar, Carolina Zheng, Magnus Saebo +5

Many applications seek to optimize LLM outputs at test time by iteratively proposing, scoring, and refining candidates over a discrete output space. Existing methods use a calibrat…

cs.CV2025

Improving the Physics of Video Generation with VJEPA-2 Reward Signal

Jianhao Yuan, Xiaofeng Zhang, Felix Friedrich +7

This is a short technical report describing the winning entry of the PhysicsIQ Challenge, presented at the Perception Test Workshop at ICCV 2025. State-of-the-art video generative…

cs.CL2025

Model Directions, Not Words: Mechanistic Topic Models Using Sparse Autoencoders

Carolina Zheng, Nicolas Beltran-Velez, Sweta Karlekar +5

Traditional topic models are effective at uncovering latent themes in large text collections. However, due to their reliance on bag-of-words representations, they struggle to captu…

stat.ML2024

Can Generative AI Solve Your In-Context Learning Problem? A Martingale Perspective

Andrew Jesson, Nicolas Beltran-Velez, David Blei

This work is about estimating when a conditional generative model (CGM) can solve an in-context learning (ICL) problem. An in-context learning (ICL) problem comprises a CGM, a data…

cs.AI2024

Hypothesis Testing the Circuit Hypothesis in LLMs

Claudia Shi, Nicolas Beltran-Velez, Achille Nazaret +5

Large language models (LLMs) demonstrate surprising capabilities, but we do not understand how they are implemented. One hypothesis suggests that these capabilities are primarily e…

cs.LG2024★ 1 cited

Treeffuser: Probabilistic Predictions via Conditional Diffusions with Gradient-Boosted Trees

Nicolas Beltran-Velez, Alessandro Antonio Grande, Achille Nazaret +2

Probabilistic prediction aims to compute predictive distributions rather than single point predictions. These distributions enable practitioners to quantify uncertainty, compute ri…

cs.LG2024★ 4 cited

Estimating the Hallucination Rate of Generative AI

Andrew Jesson, Nicolas Beltran-Velez, Quentin Chu +5

This paper presents a method for estimating the hallucination rate for in-context learning (ICL) with generative AI. In ICL, a conditional generative model (CGM) is prompted with a…