About Me
Fred Xu
Ph.D. student in Computer Science, University of California, Los Angeles
I’m a Computer Science Ph.D. student at UCLA. I research probabilistic generative modeling (flow matching and diffusion), graph learning and uncertainty quantification, with applications to finance and science. My first- and co-first-author papers have appeared at NeurIPS, KDD and ACL, and I review for NeurIPS, ICML and ICLR.
Alongside the Ph.D. I’ve done industry research at Block, across two AI research internships, and at Hitachi and Amazon, applying this work to financial fraud detection, customer risk modeling, transaction foundation models and recommendation. Before graduate school I was a software engineer at NortonLifeLock, building security and privacy products.
Beyond the technical work, my interests run to AI and society, the philosophy of AI and continental philosophy, and on this site I write about those subjects, about literature, and about the papers behind my research.
Research interests
Machine learning
Flow matching and diffusion modelsGraph learningUncertainty quantificationAnomaly and fraud detectionTime seriesScientific machine learning
Philosophy and society
AI and societyPhilosophy of AIContinental philosophy
Education
Sep 2022 – present
Ph.D. in Computer Science
University of California, Los Angeles
Sep 2013 – Mar 2018
B.S. in Computer Science and Engineering, minor in Mathematics
University of California, Los Angeles
Experience
Jan – Sep 2026
AI Research Intern
Block, Inc. · Oakland, CA
- Function-space flow matching. Proposed kernel Functional Flow Matching (kFFM), which replaces independent prior–data pairing with entropic optimal transport under a kernel-induced cost, with well-posedness and discretization-invariance guarantees; improved distributional matching over FFM, diffusion and OT baselines on time-series and PDE benchmarks. First-author paper at NeurIPS 2026.
- Graph anomaly detection for fraud. Developed EB-GAD, a training-free, label-free anomaly detector that fits a graph prior by empirical Bayes and scores nodes by closed-form finite-horizon control energy; best or tied-best AUROC on 9 of 11 benchmarks, including four financial fraud networks of up to 3.7M nodes, with margins of up to 21.7 points. First-author paper at NeurIPS 2026.
- Uncertainty quantification for GNNs. Proposed DSS-GNN, which expands node embeddings on graph-spectral and Wiener-chaos axes so a single representation supports calibrated prediction, out-of-distribution detection and distribution-shift robustness. First-author paper at NeurIPS 2026.
- Graph generation. Co-developed FlowPhon, which generates dense graphs via flow matching on graphon operators; second-author paper under review.
- Transaction foundation model. Built a GPT-style foundation model over customer transaction event sequences to model Cash App balance changes.
Aug 2025 – May 2026
STEM Specialist
Handshake AI, Inc. · Remote
- LLM post-training data. Authored and solved advanced STEM problems and evaluated LLM-generated code to support alignment and improve the generation quality of LLM agents.
Jan – Sep 2025
AI Research Intern
Block, Inc. · Oakland, CA
- Uncertainty estimation on graphs. Developed a graph neural network grounded in stochastic partial differential equations for uncertainty estimation on graph data. First-author paper at NeurIPS 2025.
- Customer risk modeling. Implemented a probabilistic machine learning model with Monte Carlo simulation to estimate customer default risk and account lifetime value.
- Time-series generation. Created a distributional diffusion model for time series built on path signatures.
Jun – Sep 2024
Research Scientist Intern
Hitachi America, Ltd. · Santa Clara, CA
- Sensorless cargo monitoring. Engineered features and built regression and time-series models on global cargo-container temperature and humidity data to estimate shipment operational risk, improving on the baseline model by 30%.
- Financial risk simulation. Ran Monte Carlo simulations over financial indicators and corporate portfolios, combined with time-series analysis, to estimate corporate financial risk under currency-rate and market shifts.
Jun – Sep 2022
Applied Scientist Intern
Amazon.com, Inc. · New York, NY
- Audience embedding for recommendation. Implemented a deep-learning bipartite graph embedding model for audience representation in recommendation and user-group behavior prediction; proposed fuzzy-set embeddings to support logical queries, outperforming the baseline by at least 30%.
Jul 2018 – May 2021
Software Engineer
NortonLifeLock Inc. · Culver City, CA
- Privacy Monitor (iOS). Developed the privacy monitor feature and client kit in Swift for the Norton Secure VPN iOS app, increasing customer interest in the privacy product by 45%.
- Norton Secure VPN (Android). Maintained and extended the Android app (10M+ installs), shipping features including split tunneling and torrenting support.
- Norton Security UWP. Developed, integrated and unit-tested core C#, Angular and C++/WinRT code for the Universal Windows Platform app; helped build the product threat model and implemented encryption, authentication and file-integrity mechanisms.
- Secure file transfer and privacy MVPs. Built a cross-platform MVP (Android, iOS, PWA) for secure file transfer using TLS, RSA, AES-256 and SHA-256 with key management in Azure Key Vault, and a Chrome extension that opts users out of data-broker websites.
Publications
NeurIPS 2026
NeurIPS 2026
NeurIPS 2026
KDD 2026
KDD 2026
TIDAL: A Temporal Causal Diffusion Framework for Visualizing Knee Osteoarthritis Treatment Outcomes
ACL 2026
Training Recipes for Agentic Reinforcement Learning in LLMs: A Survey
NeurIPS 2025
ACL 2024
Manuscript
Neural Hybrid Residual XRO Models for ENSO Forecasting
Under review
FlowPhon: Graph Generation via Flow Matching on Graphon Operators
Teaching
Jul – Aug 2023
Instructor, CS 97: Introduction to Data Science
UCLA Summer Institute
Taught advanced high-school students for college credit; rated 8.75 / 9 overall.
Teaching Assistant
UCLA Computer Science
CS 148 Introduction to Data Science, CS 247 Advanced Data Mining, CS 33 Computer Organization, CS M51A Logic Design of Digital Systems; average rating 8.4 / 9.
Service & talks
- Reviewer for NeurIPS, ICML, ICLR, WWW and CIKM, and for PLOS journals
- Talks on machine learning papers and tutorials at the UCLA Data Mining study group, student clubs and company knowledge-sharing meetings
Skills
Programming
Python, C++, SQL, Shell
ML & data
PyTorch, PyTorch Geometric, JAX, Hugging Face, scikit-learn, NumPy, pandas, Spark, AWS
LLMs
Fine-tuning and evaluation; OpenAI, Claude and Gemini APIs
Methods
Flow matching, diffusion models, uncertainty quantification, graph learning, time series, scientific ML
Languages
English, Chinese, German, Spanish