activity
20072026
most citedCapacity-achieving Sparse Superposition Codes via Approximate Message Passing Decoding

126 citations · 569 across the 45 of their papers we have counts for

collaborators

52 papers

cs.IT2026

Lossy Compression via Sparse Regression Codes: Generalized Construction and Finite-length Bounds

Galen Reeves, Ramji Venkataramanan

We study sparse regression codes (SPARCs) for lossy compression under simple greedy encoding rules, including both correlation-based and distance-based methods. We generalize the S…

stat.ML2026

Diffusion Models Observe Only Gradients: A Geometric Perspective on Score Matching Errors

Naïl B. Khelifa, Richard E. Turner, Ramji Venkataramanan

Score-based diffusion models are typically trained by minimizing the score matching error, and standard theoretical analyses rely on this quantity to bound the sampling discr…

stat.ML2026

Recursively Trained Diffusion Models: Limiting Collapse Distribution and Spectral Characterization

Naïl B. Khelifa, Richard E. Turner, Ramji Venkataramanan

Recursive training of generative models on their own outputs can lead to model collapse, a compounding drift away from the true data distribution. Existing theoretical works bound…

stat.ME2026

Inferring Change Points in Regression via Sample Weighting

Gabriel Arpino, Ramji Venkataramanan

We study the problem of identifying change points in high-dimensional generalized linear models, and propose an approach based on sample-weighted empirical risk minimization. Our m…

math.ST2026

Optimal Estimation in Orthogonally Invariant Generalized Linear Models: Spectral Initialization and Approximate Message Passing

Yihan Zhang, Hong Chang Ji, Ramji Venkataramanan +1

We consider the problem of parameter estimation from a generalized linear model with a random design matrix that is orthogonally invariant in law. Such a model allows the design ha…

stat.ML2026

Quantifying Error Propagation and Model Collapse in Diffusion Models

Nail B. Khelifa, Richard E. Turner, Ramji Venkataramanan

Machine learning models are increasingly trained or fine-tuned on synthetic data. Recursively training on such data has been observed to significantly degrade performance in a wide…