1 citations · 1 across the 9 of their papers we have counts for
12 papers
Who Gets Unmasked? Sampler-Induced Bias in Diffusion Language Models
Xujun Che, Farsheed Haque, Depeng Xu +2
Diffusion language models (dLLMs) generate by gradually unmasking a canvas, so their samplers decide not only which token to write but also when to commit it. We show that this sec…
QEncodeBench: Can Large Language Models Encode Classical Problems into Verified Quantum Oracles?
Xujun Che, Hanhan Wu, Yuchen Yuan +1
Grover search, amplitude amplification, and quantum counting all rely on the same reusable subroutine, a phase oracle, whose construction the algorithms literature takes as given:…
Privacy Amplification Without Independence: How Far Negative Dependence Carries the Guarantees of Poisson Subsampling
Xujun Che, Depeng Xu
Poisson subsampling is the default sampler in differentially private optimization because its independence makes privacy amplification tractable. Practical systems, however, are mo…
MoSign: Challenge-Response Motion-Watermark Authentication for Anonymous Virtual-Reality Users
Xujun Che, Thomas Carr, Depeng Xu +2
Social virtual reality (VR) creates a paradox. A user's body motion is a high-entropy biometric: head and hand trajectories alone re-identify users among tens of thousands with ove…
Memorization Is Not Extraction: Tight Differential-Privacy Bounds and Audit Blind Spots
Xujun Che, Depeng Xu, Shuhan Yuan
Memorization in large language models is measured through a zoo of definitions whose formal relations are unknown, and differential privacy (DP) is treated as a proxy against all o…
MAVISEG: Manifold Propagation and Visual Prototypes for Zero-Shot Open-Vocabulary Segmentation in Diffusion Transformers
Rajatsubhra Chakraborty, Xujun Che, Ritabrata Chakraborty +2
Text-to-image diffusion transformers learn about objects and scenes by learning to generate them, making them strong candidates for training-free zero-shot open-vocabulary semantic…
Abstention as an Action Can Kill Both the Reward Gradient and the KL Anchor: Collapse Law and Repair for Error-Penalized Reinforcement Learning
Xujun Che, Yuchen Yuan, Weida Zhao +1
Error-penalized scoring rules ( for a correct answer, for a wrong one, for abstaining) are increasingly prescribed against hallucination: a rational agent facing such…
StraightDP: Geometry-Aware Differential Privacy for Rectified-Flow Transformers
Xujun Che, Depeng Xu, Xintao Wu
Differentially private (DP) training of text-conditioned generative models suffers a utility cliff at strong privacy. We revisit this problem through the geometry of rectified flow…
MARLIN: De Novo Molecular Structure Elucidation from Tandem Mass Spectra without a Ground-Truth Formula
Xujun Che, Xiuxia Du, Depeng Xu
Untargeted tandem mass spectrometry (MS/MS) detects thousands of small molecules per biological sample, yet most go unidentified because they are absent from spectral libraries. Th…
Unlocking High-Fidelity Molecular Generation from Mass Spectra via Dual-Stream Line Graph Diffusion
Xujun Che, Xiuxia Du, Depeng Xu
De novo molecular generation from tandem mass spectra is a challenging inverse problem whose core difficulty lies in the circular dependency between atom-level and bond-level reaso…
Comparative Analysis of Formula and Structure Prediction from Tandem Mass Spectra
Xujun Che, Xiuxia Du, Depeng Xu
Liquid chromatography mass spectrometry (LC-MS)-based metabolomics and exposomics aim to measure detectable small molecules in biological samples. The results facilitate hypothesis…
BiasMap: Leveraging Cross-Attentions to Discover and Mitigate Hidden Social Biases in Text-to-Image Generation
Rajatsubhra Chakraborty, Xujun Che, Depeng Xu +3
Bias discovery is critical for black-box generative models, especiall text-to-image (TTI) models. Existing works predominantly focus on output-level demographic distributions, whic…