activity
20162026
most citedHierarchical Clustering with Structural Constraints

34 citations · 136 across the 27 of their papers we have counts for

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Showing 2026Show all

7 papers · 1 filter

cs.CR2026

Jailbreaking Open-Weight LLMs via Random Embedding Perturbations

Abhinav Sudhakar Dubey, Scott Sirri, Vaggos Chatziafratis +1

While open-weight models have enjoyed steady progress in capabilities and wide adoption across multiple domains, their safety remains an important concern. One key feature is the a…

cs.CL2026

Lend Me Your Eyes: Instruction-Aware Text Embeddings via Attention Relay

Yiyuan Luo, Vaggos Chatziafratis

Text embedding models trained with contrastive learning learn to follow task instructions from instruction-paired data, while instruction-tuned LLMs already know how to follow them…

cs.DS2026

Optimal VC Dimension of Contrastive Learning with Margin

Dionysis Arvanitakis, Vaggos Chatziafratis, Yiyuan Luo +1

Contrastive learning is a successful paradigm for learning -dimensional geometric representations from a collection of ``anchor--positive--negative'' triplets ,…

cs.DS2026

Strong Refutation of Ordering, Phylogenetic, and Ordinary CSPs, and New Satisfiability and Refutation Thresholds for Triplet and Quartet Reconstruction

Dionysis Arvanitakis, Vaggos Chatziafratis, Yiyuan Luo +1

We study phase transitions and algorithms for refuting CSPs arising in hierarchical clustering (as well as ranking, and ordinary CSPs). Here, variables are assigned to leaves o…

cs.DS2026

Provable Accuracy Collapse in Embedding-Based Representations under Dimensionality Mismatch

Dionysis Arvanitakis, Vaggos Chatziafratis, Yiyuan Luo

Embedding-based representations in Euclidean space are a cornerstone of modern machine learning, where a major goal is to use the \emph{smallest dimension} that fait…

cs.DS2026

Optimal Phylogenetic Reconstruction from Sampled Quartets

Dionysis Arvanitakis, Vaggos Chatziafratis, Yiyuan Luo +1

Quartet Reconstruction, the task of recovering a phylogenetic tree from smaller trees on four species called \textit{quartets}, is a well-studied problem in theoretical computer sc…

cs.LG2026

Tunable Latent Generative Priors for Compressed Sensing and Inverse Problems

Sean Gunn, Jorio Cocola, Oliver De Candido +2

Latent generative models have emerged as powerful priors for solving inverse problems. These models typically represent a class of natural signals at a single, fixed complexity, go…