activity
20242026
collaborators

8 papers

cs.LG2026

Adaptive Multi-Value Control in LLMs via Causal Activation Steering

Payel Bhattacharjee, Ravi Tandon

Large language models (LLMs) are increasingly deployed in settings where responses must reflect multiple, potentially interacting social norms and human values. Activation steering…

cs.LG2026

STAMP: Selective Task-Aware Mechanism for Text Privacy

Fengwei Tian, Payel Bhattacharjee, Heidi Hanson +3

We present STAMP (Selective Task-Aware Mechanism for Text Privacy), a new framework for task-aware text privatization that achieves an improved privacy-utility trade-off. STAMP sel…

cs.LG2026

MARS: Margin and Semantic-Aware Data Augmentation for Reward Modeling

Payel Bhattacharjee, Osvaldo Simeone, Ravi Tandon

Reward modeling is central to RLHF, RLAIF, and PPO-based alignment, but its reliability is often limited by scarce and heterogeneous human preference data. In this paper, we introd…

cs.LG2025

Conformal Sparsification for Bandwidth-Efficient Edge-Cloud Speculative Decoding

Payel Bhattacharjee, Fengwei Tian, Meiyu Zhong +3

Edge-cloud speculative decoding (SD) accelerates inference by having a cloud-based large language model (LLM) that verifies draft tokens generated by a resource-constrained small l…

cs.LG2025

PROPS: Progressively Private Self-alignment of Large Language Models

Noel Teku, Fengwei Tian, Payel Bhattacharjee +3

Alignment is a key step in developing Large Language Models (LLMs) using human feedback to ensure adherence to human values and societal norms. Dependence on human feedback raises…

cs.LG2025

Improving Epidemic Analyses with Privacy-Preserving Integration of Sensitive Data

Zihan Guan, Zhiyuan Zhao, Fengwei Tian +5

Epidemic analyses increasingly rely on heterogeneous datasets, many of which are sensitive and require strong privacy protection. Although differential privacy (DP) has become a st…

cs.CR2025

Learning to Diagnose Privately: DP-Powered LLMs for Radiology Report Classification

Payel Bhattacharjee, Fengwei Tian, Geoffrey D. Rubin +5

Large Language Models (LLMs) are increasingly adopted across domains such as education, healthcare, and finance. In healthcare, LLMs support tasks including disease diagnosis, abno…

cs.CR2024

CURATE: Scaling-up Differentially Private Causal Graph Discovery

Payel Bhattacharjee, Ravi Tandon

Causal Graph Discovery (CGD) is the process of estimating the underlying probabilistic graphical model that represents joint distribution of features of a dataset. CGD-algorithms a…