I am a PhD student in Urban Systems at NYU Tandon, advised by Debra Laefer in the Urban Modeling Group. My research asks one question: when a machine reports on the physical world, how far can the report be trusted, and does it say so. I work on that from the measurement up. Repeat lidar scans of the same unchanged street disagree, and I measure by how much. Then I ask what a reward or a benchmark can certify about an agent that reports on data like that.

Three pieces of that work

• civic-honesty-benchmark. A 596-question live-data benchmark over NYC street-pavement open data, with gold answers recomputed against the live API. Claude Haiku 4.5 quoted the documented reliability caveat on every answer that needed one and disclosed a discoverable data defect in 0 of 108 eligible answers.
• Scoring Rules Certify Reporting, Not Seeking. A proof that level-based proper scoring-rule rewards certify honest reporting but not information-seeking, for every strictly proper binary rule. Poster at the IROS 2026 Full-Shift Robot Co-Workers workshop (OpenReview).
• State-Wise Constrained Policy Shaping for Zero-Shot Runtime Behavior Steering. A post-training supervisor that enforces safety norms on DQN driving agents in HighwayEnv. Collisions fell 97% in-distribution and 99% zero-shot. Oral at the AAAI-26 Workshop on AI Governance, with T. Howell, R. McPherson and V. Sarathy. Code.

Before the PhD

• Full-stack software engineer at Cyvl, 2025 to 2026. Production pipelines over petabyte-scale lidar and street imagery for municipal road networks. I built the embedding pipeline that indexes 500k+ street images per city for sub-second semantic search, and designed the ingestion pipeline that won NYC DEP's Environmental Technology Lab Challenge.
• Swarm robotics research intern at the Air Force Research Laboratory, summer 2025. Multi-agent reinforcement learning under communication constraints.
• M.S. in Computer Science (Human-Robot Interaction) at Tufts, where I led the back-end of GailBot in the Human Interaction Lab and built sphero-swarm. B.S. in Computer Science at WPI, where my capstone built a land-acquisition platform the City of Worcester still runs.

Find me

• Academic page, with publications and CV: phbui.github.io/academic
• Portfolio, with everything else: phbui.github.io
• LinkedIn · bilphui@gmail.com

The pinned repos below are the ones that best represent this. The rest is older coursework and hackathon builds.