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Xihang Shan · 单夕航
I am committed to building AI systems that test before they trust.
I am Xihang Shan (单夕航), a mathematics undergraduate at Xiamen University. My research connects machine learning, AI agents, causal decision-making, graph reasoning, and mathematical modeling. I am grateful to my undergraduate mentors, Prof. Da Zhou and Prof. Ye Luo, for their guidance.
News
Recent updates
Summer research collaboration at HKUST with Prof. Can Yang.
Completed the NeurIPS 2026 rebuttal; post-rebuttal reviews: 4/4/5.
Three manuscripts submitted to AAAI 2027.
National-level undergraduate research program launched at Xiamen University.
Attended the Cryptography and Mathematics Summer School at the Institute of Information Engineering, Chinese Academy of Sciences, and was named an Outstanding Student.
Selected manuscripts
Research that questions its assumptions.
Across causal learning, agents, and graphs, I design controls that reveal when external knowledge helps—and when a model should refuse it.
PRCD-MAP: Learning How Much to Trust Imperfect Priors in Causal Discovery
Learns edge-specific trust from data, using useful prior structure while safely reverting to data-only discovery when the prior is misleading.
Testing Before Trusting: Causal Skeptic Bandits under Unreliable Historical Evidence
Treats historical causal knowledge as a hypothesis to be tested online; diagnostic falsification and a causal veto keep misleading graphs from steering decisions.
DeltaNAR: Learning What to Reuse and What to Recompute in Neural Algorithmic Reasoning
Separates state that remains valid after a graph update from state that must be recomputed, enabling incremental reasoning without unsafe copying.
Failure-Learning Claims Need Controls: A Claim-Control Evaluation of Language Agents
Uses claim-matched controls to distinguish repair, transfer, target-solving, and executable validity from ordinary task success.
Bounded Path Context: Visible Path History in LLM-Based KGQA
Uses bounded visible path history to reduce prompt exposure while preserving effective, auditable symbolic reasoning.
Recipe-Controlled Decoder Audit for Structural Knowledge-Graph Completion
Shows how decoder choice and training recipe can confound structural KGC comparisons, motivating controlled reporting across architectures and datasets.
* Corresponding author.
Other projects
Research Memory Auditor
Bounded, claim-relevant memory views and fail-closed evidence auditing for research agents.
Open repository ↗Boolean Function Structure
Walsh-spectral affine approximation, derivative-guided affine covers, and feedforward sequence recovery.
Repository & report ↗LocSource
Conservative, auditable transcript-ownership proposals for Xenium post-segmentation analysis.
Repository & report ↗Education
Education

Xiamen University
B.S. in Mathematics and Applied Mathematics
School of Mathematical Sciences
Honors
Honors

Fujian First Prize
National Undergraduate Mathematical Modeling Contest · Team Leader

Fujian Third Prize
National Undergraduate Mathematical Modeling Contest · Team Leader
Outstanding Student
Cryptography & Mathematics Summer School
Beyond research
Things I enjoy away from the screen.
Basketball
Long-time NBA fan · Always happy to talk basketball
Billiards
Bridge
Piano
Touch Rugby
Contact
