collaborators

9 papers

cs.CL2026

Scalable Prompt Routing via Fine-Grained Latent Task Discovery

Yunyi Zhang, Soji Adeshina, Sheng Guan +5

Prompt routing dynamically selects the most appropriate large language model from a pool of candidates for each query, optimizing performance while managing costs. As model pools s…

cs.LG2026

Consensus is Not Verification: Why Crowd Wisdom Strategies Fail for LLM Truthfulness

Yegor Denisov-Blanch, Joshua Kazdan, Jessica Chudnovsky +4

Pass@k and other methods of scaling inference compute can improve language model performance in domains with external verifiers, including mathematics and code, where incorrect can…

cs.LG2026

Train Less, Learn More: Adaptive Efficient Rollout Optimization for Group-Based Reinforcement Learning

Zhi Zhang, Zhen Han, Costas Mavromatis +9

Reinforcement learning (RL) plays a central role in large language model (LLM) post-training. Among existing approaches, Group Relative Policy Optimization (GRPO) is widely used, e…

cs.CL2025

BYOKG-RAG: Multi-Strategy Graph Retrieval for Knowledge Graph Question Answering

Costas Mavromatis, Soji Adeshina, Vassilis N. Ioannidis +6

Knowledge graph question answering (KGQA) presents significant challenges due to the structural and semantic variations across input graphs. Existing works rely on Large Language M…

cs.IR2025

Hierarchical Lexical Graph for Enhanced Multi-Hop Retrieval

Abdellah Ghassel, Ian Robinson, Gabriel Tanase +6

Retrieval-Augmented Generation (RAG) grounds large language models in external evidence, yet it still falters when answers must be pieced together across semantically distant docum…

cs.LG2025

HybGRAG: Hybrid Retrieval-Augmented Generation on Textual and Relational Knowledge Bases

Meng-Chieh Lee, Qi Zhu, Costas Mavromatis +5

Given a semi-structured knowledge base (SKB), where text documents are interconnected by relations, how can we effectively retrieve relevant information to answer user questions? R…