P Sam Sahil

P Sam Sahil

Visiting UG Research Fellow & RA Intern

Harvard University · Northwestern University

Biography

I am a graduate researcher in Computer Science Engineering, focusing on NLP, Interpretability, Social Computing, and Safety & Alignment in Large Language Models. My research builds pipelines that analyze biases and causal mechanisms within transformer models.

I am currently a Visiting Undergraduate Research Fellow at Harvard University and a Research Assistant Intern at Northwestern University. I recently collaborated with the University of Oxford on mechanistic interpretability and AI safety, and previously worked with the University of Hamburg (HCDS Lab) and NIT Agartala.

Interests
  • Interpretability
  • NLP
  • Social Computing
  • Safety & Alignment
Education
  • B.E. in Computer Science Engineering

    Visvesvaraya Technological University (VTU), India

    Nov 2022 – Aug 2026 · 79% (First Class with Distinction)

Experience
Visiting Undergraduate Research Fellow & RA Intern
Harvard University & Northwestern University
Remote
Jan 2026 – Aug 2026
  • Architected a high-throughput spatio-temporal data pipeline in Python to ingest, clean, and process ~20M scanned articles (~350GB) from the American Stories dataset.
  • Engineered NLP preprocessing workflows and geo-tagging modules to extract structured location and entity metadata from historical U.S. newspaper archives.
  • Developed analytical frameworks to quantify and detect reporting biases and sentiment shifts across regional publications over time.
Research Collaborator (Interpretability & AI Safety)
University of Oxford
Collaborative Research · Remote
Feb 2026 – Mar 2026
  • Developed the Patchscope-For-Neuron pipeline to causally test neuron reactivation in Gemma-2-2B by injecting residual stream vectors into new contexts via TransformerLens. Repo
  • Integrated Sparse Autoencoders (SAEs) to decompose hidden representations into interpretable features, verifying how neurons respond to intrinsic semantic features rather than original textual context.
  • Co-authored "Beyond Auto-Interpretability: Mapping a Hierarchical Math Circuit in Gemma-2-2B via Gradient-Based Patchscopes". Report · Repo
Research Intern
University of Hamburg (HCDS Lab), Germany
Remote
Aug 2025 – Present
  • Co-first authored research on the illusion of cross-lingual safety transfer in LLMs, developing a Latent Geometric Framework to evaluate hidden-state refusal representations across African languages using the novel LoDNA dataset.
  • Co-Organizer, SemEval 2026 Task 9: led a global competition on multilingual online polarization detection (Top 6 on CodaLab, 1,000+ participants). Website
  • POLAR: developed scalable scripts for classification and dataset splitting across 22+ languages (110K+ samples); integrated LLM-based pipelines for few-shot and zero-shot learning on GPU clusters.
  • AI4Democracy: built an automated monitoring platform to detect and track antidemocratic narratives across 500+ daily web-scraped sources using RoBERTa and Llama 2 / Gemma 2 pipelines.
  • Contributed to the AI-MAP project, supported by the Google Award for Inclusion Research.
Research Intern
National Institute of Technology Agartala
Remote
Jan 2025 – Dec 2025
  • SemEval-2025 Task 11 (Multilingual Multi-label Emotion Detection): achieved top-10 ranks across multiple languages out of 720 participants — Russian 7th, French 8th, Hausa 8th, Hindi 9th. Paper

🗞️ News

🏆 Awards & Honors

Best Paper Award — EEUCA, ACL 2026, for the POLAR benchmark.
Runner-Up Award — SemEval, ACL 2026, for SemEval-2026 Task 9.
Featured in Prominent Media — Agents of Chaos highlighted in Science, Times of India, ZDNet, and Import AI (Jack Clark), reaching 5M+ views on X.
Top 6 Benchmark Rank on CodaLab for the organized SemEval 2026 Task 9 (out of 1,000+ participants and 9,800 submissions).
Top 10 Ranks in SemEval-2025 Task 11 out of 720 participants (Russian 7th, French 8th, Hausa 8th, Hindi 9th).

📚 Publications

185+ Citations · h-index: 3 · Google Scholar Profile
Usman Naseem, …, P Sam Sahil, …, Seid Muhie Yimam
Official Task Description Paper · ACL Anthology (SemEval 2026)🥈 Runner-Up Award

Co-organized a global shared task with 67 participating teams, analyzing state-of-the-art LLM performance on online polarization across 22 languages.

Usman Naseem, …, P Sam Sahil, …, Seid Muhie Yimam
ACL 2026 Findings🏆 Best Paper Award (EEUCA)

Developed a comprehensive benchmark for detecting online polarization across 25+ languages.

LLM Safety Alignment in Low-Resource Languages: A Systematic Literature Review
Lemofouet Valdini Douglace, …, P Sam Sahil, …, Shamsuddeen Hassan Muhammad
Accepted (Poster) · IJCAI 2026 Workshop LM4UC

Conducted a Systematic Literature Review (PRISMA 2020) of LLM safety alignment in African and low-resource languages; analyzed 50 papers to identify gaps in culturally specific harms and benchmarking methods.

Abigail Oppong*, P Sam Sahil*, …, Seid Muhie Yimam (*equal contribution)
Preprint

Proposed a Latent Geometric Framework to probe hidden-state refusal representations, demonstrating severe cross-lingual transfer limitations across Twi, Hausa, Amharic, and Swahili using the LoDNA dataset.

Natalie Shapira, …, P Sam Sahil, …, David Bau
Technical Report (arXiv:2602.20021)

Adversarial stress-testing of agentic AI with researchers from Harvard, MIT, and Stanford, identifying critical vulnerabilities in multi-user interaction security models. Featured in Science, Times of India, ZDNet, and Import AI.

💻 Selected Projects

The Ghost in the Machine

Interpretable AI-text detection using Gemma-2-2B and Sparse Autoencoders: mapped Layer-20 residual stream activations to Sparse Feature Vectors, achieving 99% accuracy on DAIGT V2 with an XGBoost classifier. Top predictive features validated via Neuronpedia.

Automated Circuit Analysis

Designed a fully automated pipeline for discovering, interpreting, and validating task-specific causal circuits in transformer models.

Llama-3.2 Vision Radiology

Fine-tuned Llama-3.2-11B-Vision-Instruct via LoRA for efficient adaptation to radiology image captioning using Unsloth.

AI4Democracy Platform

Automated monitoring platform detecting antidemocratic narratives across 500+ daily web-scraped sources, with a multi-tiered classification pipeline using RoBERTa, Llama 2, and Gemma 2.

🛠️ Technical Skills

Programming
Python C++ LaTeX
Libraries & Tools
TensorFlow PyTorch scikit-learn Hugging Face Pandas NumPy Matplotlib Seaborn