NeurIPS 2026 Papers

Conference on Neural Information Processing Systems

Decision breakdown

6,437papers

Counted from the official paper list; may differ slightly from the number the conference announced.

  • Oral
    991.5%
  • Spotlight
    2403.7%
  • Poster
    6,09894.7%

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ReVMap: Vectorized Global Mapping via Connectivity-Aware Local Map Fusion

Hongjae Shin, Jungho Kim, Donghyuk Kwak, Myeongjun Kim, Seunghoon Yu, Jiyong Oh, Jun Won Choi

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Large-scale annotation of vectorized high-definition (HD) maps requires substantial human effort, motivating local-to-global auto-labeling that incrementally constructs global maps from local vector predictions. In this formulation, limited reliability management allows inaccurate predictions to be accumulated and reused as priors, causing persistent error propagation across iterations. We propose ReVMap, a local-to-global framework for reliable vectorized global map construction. ReVMap introduces a reliability-aware map evolution strategy that unifies uncertainty-guided prior reuse with revisable global map updates. To realize this strategy, ReVMap estimates localization uncertainty for vectorized local map elements and propagates these reliability cues to the accumulated global map. The resulting uncertainty-aware global representation guides subsequent local prediction and facilitates revisable integration through learning-based local-to-global connectivity estimation and uncertainty-aware fusion. ReVMap achieves state-of-the-art results on nuScenes and Argoverse2, with 36.1 mGAP, 43.4 miECM, and 58.0 local mAP on nuScenes, and 62.1 mGAP, 62.5 miECM, and 77.0 local mAP on Argoverse2.

Poster
ReSET: Accurate Latency-Critical NVFP4 Reasoning via Step-Aware Temperature Scaling

Sihwa Lee, Janghwan Lee, Donghoon Yoo, Jae Gon Kim, Hanyul Ryu, Soojung Ryu, Jungwook Choi

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Large reasoning models (LRMs) improve complex problem-solving by generating long intermediate reasoning traces, but this substantially increases inference costs. NVFP4 inference offers a promising approach to reduce both computational and memory costs through hardware-supported low-precision execution. However, directly applying NVFP4 to LRMs introduces two practical limitations: reasoning accuracy degrades under quantization, and existing NVFP4 kernels do not fully realize latency benefits in small-batch autoregressive decoding. In this work, we analyze the effect of NVFP4 quantization on token-level uncertainty during reasoning. We show that quantization increases incorrect sampling at low-entropy symbolic tokens, while causing over-concentration on a small set of tokens in high-uncertainty reasoning steps. Based on this observation, we propose \textbf{ReSET}, a reasoning-step entropy-based temperature-scaling method that estimates step-level uncertainty online and adapts the decoding temperature using both token-level and step-level entropy signals. To address the latency gap, we further design a CUDA-core small-$M$ NVFP4 kernel for latency-critical autoregressive decoding. Across reasoning benchmarks and model scales, ReSET improves NVFP4 reasoning accuracy by up to $\sim$2 points over the NVFP4 baseline. Our CUDA-core small-$M$ kernel further improves latency-critical decoding, delivering up to $2.5\times$ kernel-level speedup over NVFP4 vLLM and approximately $2\times$ end-to-end decoding speedup over BF16. Code will be released.

Poster
RSPReg: Reliability-aware Structural Prototype Learning for Point Cloud Registration

Arzigul Ahat, Eksan Firkat, Askar Hamdulla

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Point cloud registration remains challenging in scenarios with low overlap, repetitive structures, and local geometric ambiguities, where candidate correspondences established based on local geometric similarity often lack global structural consistency and are prone to unreliable matches. To address this issue, this paper proposes RSPReg, a reliability-aware structural prototype learning framework for robust point cloud registration. RSPReg learns structural prototypes from rotation-invariant coarse-level superpoint features to characterize the structural attributes of local regions within the entire point cloud. These prototypes are further introduced as structural priors into cross-cloud correspondence reasoning, thereby improving the structural consistency of candidate correspondences. Furthermore, RSPReg estimates the uncertainty of structural prototypes and adaptively modulates the role of structural priors in the matching and pose estimation processes, reducing the negative impact of ambiguous and non-overlapping regions on registration results. Experiments on 3DMatch, 3DLoMatch, KITTI, and ETH demonstrate that RSPReg achieves the highest registration recall and exhibits clear advantages in low-overlap and cross-domain scenarios.

Poster
RAMA: Resistance-Aware Multi-Hop Aggregation Graph Representation Learning for Robust Ethereum Account Classification

Zhaowei Liu, zengyang zhang, HaitaoYang, Yao Shan, Xiangfu Zhao, Yongchao Song

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Fraudulent behaviors in Ethereum, such as Ponzi schemes and phishing attacks, pose persistent threats to blockchain security. Classifying high-risk accounts is crucial for mitigating these threats. Given the graph-structured nature of Ethereum transactions, Graph Neural Networks (GNNs) are widely adopted for this task. However, conventional GNNs rely on local aggregation and treat all edges equally, which amplifies structural noise and limits the ability to capture weak but semantically meaningful connections. This limitation arises from the inability to distinguish informative links from spurious ones during message passing, especially in noisy and long-range transaction graphs. To address this, we propose RAMA, a Resistance-Aware Multi-hop Aggregation framework that reweights edges using resistance distance to reduce the influence of noisy links while preserving important topological information. It also employs attention-based multi-hop aggregation to effectively integrate both local and global transaction patterns. Experiments on real-world Ethereum datasets show that RAMA consistently outperforms strong baselines in Macro-F1 and remains robust under edge perturbations, demonstrating its effectiveness for practical account classification in blockchain environments.

Spotlight
RADAR: Routing Agents via Difficulty-Aware Recovery

Haizhou Du, Jinze Zhao, HuaiCheng Yan

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Multi-agent systems (MAS) have emerged as a dominant paradigm where agent routing is a bottleneck for balancing performance and cost. However, existing agent routing methods suffer from the prohibitive cost of exhaustive benchmark construction and the neglect of query complexity essential for mixed tasks. To address this issue, we propose the RADAR (Routing Agents via Difficulty-Aware Recovery) framework. RADAR enables accurate decision-making under limited evaluation cost through two complementary modules. MatrixComp module employs structure-aware matrix completion to recover global performance profiles from sparse observations. Furthermore, DiffMatch module extracts reasoning meta-features for fine-grained alignment via a difficulty-calibrated retrieval mechanism. Extensive experiments demonstrate that RADAR maintains performance equal with state-of-the-art baselines while reducing the cost of benchmark construction by at least 33%.

Poster
QuantDemoire: Quantization with Outlier Aware for Image Demoiréing

Kewei Zhang, Xiaoyang Liu, Kai Liu, Weihang Zhang, Mengfan Wang, Yifan Fu, Yulun Zhang

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Demoir\'eing aims to remove moir\'e artifacts that often occur in images. While recent deep learning-based methods have achieved promising results, they typically require substantial computational resources, limiting their deployment on edge devices. Model quantization offers a compelling solution. However, directly applying existing quantization methods to demoir\'eing models introduces severe performance degradation. The main reasons are distribution outliers and weakened representations in smooth regions. To address these issues, we propose QuantDemoire, a post-training quantization framework tailored to demoir\'eing. It contains two key components. **First**, we introduce an outlier-aware quantizer to reduce errors from outliers. It uses sampling-based range estimation to reduce activation outliers and keeps a few extreme weights in FP16 with negligible cost. **Second**, we design a frequency-aware calibration strategy. It emphasizes low- and mid-frequency components during fine-tuning, which mitigates banding artifacts caused by low-bit quantization. Experiments validate that our QuantDemoire achieves large reductions in parameters and computation while maintaining quality. Meanwhile, it outperforms existing quantization methods by over **4 dB** on W4A4. We implement a CUDA kernel for the mixed-precision branch and achieve a 2.3$\times$ end-to-end speedup on an RTX 4090 GPU. Code will be made public.

Poster
Progressive Memory Transformer: Memory-Aware Attention for Time-Series

Tord Sture Stangeland, Andreas Köhler, Steffen Maeland, Adin Ramirez Rivera

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Time-series carry structure simultaneously at multiple scales (fine-grained variation, mid-range motifs, and global properties) and downstream tasks operate at correspondingly different scales. Most existing self-supervised learning approaches supervise representations globally via instance-level contrastive losses and limited temporal neighborhood supervision, but do not explicitly exploit the structural hierarchy. We propose a learning framework that explicitly enforces a structural hierarchy across three scales independently: a local objective for token continuity, a mid-range objective for window-level motifs, and a global objective for sequence-level agreement. Realizing this framework requires the backbone to expose a representation at each scale; we introduce \textbf{Progressive Memory Transformer} (PMT), which augments a transformer with writable, window-aligned memory that exposes the mid-range scale alongside the token and sequence-level representations conventional transformers already provide. Across seven UCR/UEA/UCI classification benchmarks, a cue-retention probe, and two forecasting benchmarks, PMT learns representations that probe well at the global, mid-range, and local scales---strong low-label classification (1--5\% labels), competitive forecasting performance across multiple horizons, and quantitative and qualitative evidence that memory states capture mid-range motifs.

Poster
Progress-Aware Distillation for Mitigating Stagnation in Small Language Model Agents

Yuanpu Cao, Saket Sathe, Hanyu Wang, Ziyi Yin, Fenglong Ma, Jinghui Chen

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While LLM-based agent systems have demonstrated remarkable proficiency in reasoning and solving complex real-world tasks, they also come with substantial token consumption and inference latency, limiting their practical deployment. To enhance the efficiency of agent systems, recent efforts have focused on transferring agentic capabilities from large-scale models to small language models (SLMs) via supervised fine-tuning-based distillation. Nevertheless, as interaction trajectories grow longer, involving extended reasoning-action chains and extensive environmental feedback, distilled student agents tend to experience progress stagnation: becoming trapped in unproductive loops characterized by persistent failed strategies and difficulty making meaningful progress. Our systematic analysis shows that this phenomenon consistently occurs across diverse SLMs and task domains. To address this issue, we propose Progress-Aware Distillation (ProD), which explicitly detects and penalizes stagnation in student-generated trajectories. ProD encodes the stagnation gap between student and teacher into an adaptive margin for dynamically penalizing possible stagnation. By iteratively applying this procedure, ProD enables student agents to progressively approximate teacher behavior. Extensive experiments involving 8 SLMs, ranging from 0.6B to 8B parameters, on both in-domain and out-of-domain benchmarks, demonstrate that ProD substantially mitigates progress stagnation while enhancing both the success rates and task-completion efficiency of distilled SLM agents.

Poster
Process-Aware LNS for Large-Scale MILP via Context-Enhanced Fine-Tuned LLM-driven Selector

An Yan, Huigen Ye, Hua Xu, Jiahao Zhang

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Solving large-scale Mixed-Integer Linear Programming (MILP) problems involving millions of variables is critical for industrial applications but notoriously intractable due to combinatorial explosion. While Large Neighborhood Search (LNS) has emerged as the premier heuristic strategy for tackling such scales, its efficacy hinges entirely on the underlying neighborhood selection mechanism. Recent Large Language Model (LLM)-driven LNS frameworks show remarkable promise but suffer from fundamental flaws: they lack generalizability across diverse problem classes and rely on static selection paradigms that remain entirely blind to the shifting dynamics of the iterative optimization process. To overcome this rigidity, we propose PALL, a Process-Aware Evolutionary LNS framework guided by a Context-Enhanced Fine-Tuned LLM-driven Selector. Instead of deploying a monolithic operator, PALL leverages an offline-evolved diverse operator ensemble and dynamically synchronizes the search strategy with evolving optimization states. Specifically, we fine-tune an 8B-parameter LLM on high-quality hindsight oracle trajectories to adaptively perform optimal operator selection. To bolster the LLM's sequential decision-making, we introduce a context-enhanced reasoning mechanism that leverages historical operator trajectories and optimization rewards as inferential feedback. Extensive evaluations on standard million-variable MILP benchmarks demonstrate that PALL achieves state-of-the-art performance. Supported by an asynchronous deployment strategy, it not only consistently outperforms commercial solvers like Gurobi and classical LNS algorithms but also delivers over a $6\times$ acceleration compared to state-of-the-art LLM-driven LNS frameworks.

Poster
ProQuant: Progressive Quantization-aware Training for Edge MLLMs

Yufei Xue, Yushi Huang, Jiawei Shao, Pingcheng Dong, Yonghao Tan, Shiyao Li, Kwang-Ting Cheng, Jun Zhang

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Multi-modal large language models (MLLMs) with impressive perception and understanding capabilities will enable a range of downstream applications. However, their substantial computational and memory requirements hinder the real-world implementation, particularly for resources-constrained edge devices. Quantization has emerged as an effective solution for deploying large models. While post-training quantization (PTQ) successfully retrains the performance at moderate bit-width (\textit{e.g.}, W8A8), it suffers from severe performance degradation under low-bit quantization (\textit{e.g.}, W4A8/W8A8), especially for small-scale models that are more suitable for edge deployment. In this paper, we propose \texttt{ProQuant}, a novel weight-activation quantization-aware training (QAT) framework tailored for low-bit MLLMs. First, to align the limited finetuning dataset distribution with the pretrained dataset distribution, we propose a self-relabeling (SRL) scheme to resample the responses of the open-source multimodal dataset. Second, we are the \textit{first} to take a decoupled view of multi-modal (MM) understanding and language modeling abilities. We propose a progressive block activation (PBA) mechanism to prioritize the MM understanding recovery. We also introduce a vision-sensitive factor $\vec{\tau}$ that effectively identifies the MM-critical layers. Extensive experiments across various benchmarks, covering models with 2B$\sim$8B parameters, show that \texttt{ProQuant} significantly outperforms existing methods. For example, our W4A8 \texttt{Qwen3-VL-2B-Instruct} improves average accuracy by impressively 6.6\% and achieves performance comparable to full precision counterparts with only $\sim$1\% performance drop. Code will be released upon acceptance.

Poster
Pref-DetectGPT: Unveiling Machine-Generated Text via Preference-Aware Curvature Measurement

Jiahao Wang, Feifei Kou, Zhongbao Zhang, Jiwei Zhang, Lei Shi, Pengfei ZHANG, Suguo Zhu, Mingying Xu

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The widespread deployment of large language models (LLMs) has made reliable detection of machine-generated text increasingly critical. Recent curvature-based detectors introduce perturbations to candidate text and compute curvature as the log probability difference between original and perturbed variants using advanced surrogate models. However, such curvature measurements only capture weak discrepancies between machine-generated and human-written text. We propose $\textbf{Pref-DetectGPT}$, a training-free method that introduces preference-aware curvature measurement by leveraging the implicit preference capabilities of preference-optimized surrogate models. Specifically, we construct an implicit reward model from the preference-optimized policy to score both original and perturbed text, and redefine curvature as their normalized deviation, which serves as a significantly stronger signal for distinguishing machine-generated text from human-written text. Empirical evaluations across multiple public benchmark datasets demonstrate that Pref-DetectGPT achieves state-of-the-art detection performance with relative improvements of 3.49\%, 3.13\%, and 10.66\% in AUROC, AUPR, and TPR5\%, while exhibiting strong robustness against various adversarial attacks and input lengths.

Poster
Position-aware eXplanation: A Model-Agnostic Framework for Positional Attributions

Chaehyeon Kim, Gary Weissman, Eric Wong

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Transformer predictions depend on positional embeddings, which are known to produce biases such as first- and last-token dominance. However, feature attribution methods implicitly entangle influence from positions with features into a single opaque importance score per feature. To uncover these positional effects, we propose Position-aware eXplanation (PaX), a model-agnostic framework that transforms standard attribution methods to jointly produce feature and position attributions. PaX additionally produces counterfactual positional explanations: actionable scores quantifying how the prediction changes when a feature is relocated. We use PaX to generalize perturbation-, gradient-, and boundary-based attribution methods across vision, language, and clinical time-series benchmarks with no architectural changes. We demonstrate that separating positional effects improves both feature and position attribution faithfulness by 17.5% / 55% and 16.8% / 43%, respectively (insertion / deletion). In a case study on sepsis forecasting, we find that PaX recovers clinically validated bedside signals that standard attributions miss.

Poster
PolySplat: Workload-Regime-Aware Rasterization for 3D Gaussian Splatting

Longzan Luo, Bin Cui, Xupeng Miao

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Rasterization dictates the interactive budget of 3D Gaussian Splatting (3DGS). However, the comparative speed of modern CUDA rasterizers is typically evaluated on a narrow canonical benchmark, masking severe regime-dependent performance reversals. This limited scope hides three critical kernel-level bottlenecks: warp lane underutilization, exposed global-memory latency during pixel shading, and terminal-tail penalties from hardware thread scheduling. In this paper, we present PolySplat, a workload-regime-aware 3DGS rasterizer designed to overcome these inefficiencies. PolySplat introduces a warp-saturating tile-key emitter with adaptive three-way dispatch, asynchronous shared-memory staging in the render kernel, and a persistent kernel architecture with centralized atomic dispatch to strictly bound tail latency. To rigorously validate our system, we introduce an extended 76-target benchmark that achieves comprehensive workload-regime coverage by stratifying targets across extreme Gaussian counts (up to 56.5M), high resolutions (up to 9K), and six diverse scene categories. Evaluated on this comprehensive suite, PolySplat achieves dataset-balanced geometric-mean speedups of 1.26x to 6.48x over state-of-the-art rasterizers at lossless visual quality. Notably, under sustained 60Hz interaction at extreme resolutions, PolySplat strictly meets 1-vsync display deadlines where existing renderers suffer from massive queue divergence and input-to-photon lag.

Poster
Polestar: Drift-Aware Cache Calibration and Token Commitment for Efficient Inference of Diffusion LLMs

Mingyu Lee, Akshat Ramachandran, Souvik Kundu, Tushar Krishna

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The inference efficiency of diffusion large language models (dLLMs) is constrained by two challenges: bidirectional attention precludes efficient KV-cache reuse, while increasing decoding parallelism with static confidence thresholds can compromise generation quality. We observe that both challenges arise from a shared phenomenon: as tokens are decoded, their contextual integration through bidirectional attention causes token representations to drift (evolve) across decoding steps. This insight motivates Polestar, a training-free inference framework that uses token representation drift as a unified signal to jointly address both challenges. Polestar comprises two components: Polestar-Cache, which identifies stale KV-cache positions via drift and performs sparse KV-cache refreshes to enable efficient reuse, and Polestar-Commit, which detects sharp drift events to reliably identify commit-ready tokens. Across mathematics and coding benchmarks on several dLLM families, Polestar sets a new state of the art on the accuracy-throughput Pareto frontier, achieving up to 10.73% accuracy improvement, up to 3.7x higher throughput, and high decoding parallelism of 3.67 tokens per forward pass over existing baselines.

Poster
Pessimistic Latent Task-aware Optimization for Robust Offline Meta-Reinforcement Learning

Chang-Hoon Jeong, Kisung Shin, Hanwool Sul, Byoung-Tak Zhang

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Context-based offline meta-reinforcement learning (COMRL) has progressed almost entirely through better task representations: separating task identity from behavior-policy artifacts so that the latent reflects the task information alone. The implicit expectation has been that a clean representation will transfer to out-of-distribution (OOD) tasks. However, on an OOD task the encoder produces a latent outside the training support, where the policy has never been trained. We address this gap with Pessimistic Latent Task-aware Optimization (PLATO), which exposes the policy to off-support latents at training time. PLATO assumes a mild manifold hypothesis: task latents lie on a low-dimensional manifold, with OOD tasks further from the training centroid. It exploits this geometry by perturbing inferred latents outward from the centroid to synthesize counterfactual tasks; a learned decoder ensemble then rolls out short trajectories at the perturbed latent, and the policy is updated on the imagined transitions under a pessimism weight that down-weights steps where the ensemble is unconfident. We prove that the perturbation reaches off-support by a controllable margin, that the epistemic disagreement at the perturbed latent is non-vanishing, and that the OOD generalization gap is bounded by the same perturbation reach. On eight MuJoCo continuous-control benchmarks, PLATO consistently improves out-of-distribution returns over strong COMRL baselines while remaining competitive in-distribution.

Poster
Partition-Aware Unlearning for Removing Spurious Correlations in Large Vision-Language Models

Aditi Sarker, Nazreen Shah, Rafi Ibn Sultan, Rhongho Jang, Dongxiao Zhu, Prashant Khanduri

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Large Vision-Language Models (LVLMs) achieve strong performance across many multimodal tasks; however, they often exploit spurious object-background correlations, resulting in predictions driven by contextual shortcuts rather than object-relevant visual evidence. Despite growing interest in hallucination and robustness evaluation, existing benchmarks provide limited control over whether model predictions are grounded in the target object or induced by correlated background cues. In this work, we introduce PURGE (Partition-aware Unlearning for Removing spurious-correlation Generated Errors), a framework for constructing, benchmarking, and mitigating spurious-correlation-induced failures in LVLMs. The framework consists of two components: (1) Structured dataset construction, wherein we develop three complementary structured data construction strategies that partition examples by object-relevant evidence and spurious background cues, enabling controlled diagnosis of shortcut reliance; and (2) Partition-aware unlearning, which uses these partitions to selectively remove spurious object-background associations while preserving object-based reasoning. We evaluate the PURGE framework across multiple LVLMs, including LLaVA-1.6-7B, Qwen3-VL-8B-Instruct, and Qwen3.5-9B, together with CLIP as a vision-language encoder, on a diverse suite of benchmarks, including CHAIR, POPE, Causal-HalBench, MM-SpuBench, AMBER, MMHal, and Waterbirds. Our results show that PURGE consistently reduces hallucinations and spurious-correlation-driven errors while maintaining or improving overall performance, providing both a reusable evaluation protocol and an effective mitigation framework for more reliable LVLMs.

Poster
PRISM: Prior Rectification and Uncertainty-Aware Structure Modeling for Diffusion-Based Text Image Super-Resolution

Zihang Xu, Xiaoyang Liu, Yulun Zhang, Xiaokang Yang

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Text image super-resolution (Text-SR) requires more than visually plausible detail synthesis: slight errors in stroke topology may alter character identity and break readability. Existing methods improve text fidelity with stronger recognitive or generative priors, yet they still face two unresolved challenges under severe degradation: the text condition extracted from low-quality inputs can itself be unreliable, and a plausible global prior does not fully determine fine-grained stroke boundaries. We present PRISM, a single-step diffusion-based Text-SR framework that addresses these two challenges through Flow-Matching Prior Rectification (FMPR) and a Structure-guided Uncertainty-aware Residual Encoder (SURE). FMPR constructs a privileged training-time prior from paired low-quality/high-quality latents and learns a flow matching that transports degraded embeddings toward this restoration-oriented prior space, yielding more accurate and reliable global text guidance. SURE further predicts uncertainty-aware structural residuals to selectively absorb reliable local boundary evidence while suppressing ambiguous stroke cues. Together, these components enable explicit global prior rectification and local structure refinement within a single diffusion restoration pass. Experiments on both synthetic and real-world benchmarks show that PRISM achieves state-of-the-art performance with millisecond-level inference.

Poster
PAIR: Prefix-Aware Internal Reward Model for Multi-Turn Agent Optimization

Wonjoong Kim, Yeonjun In, Sangwu Park, Dongha Lee, Chanyoung Park

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A significant hurdle for current LLMs is the execution of complex, multi-stage tasks. Group Relative Policy Optimization (GRPO) has been emerging as a leading choice, but its reliance on sparse outcome rewards severely limits credit assignment across intermediate steps. Existing remedies—running full rollouts to assign step-level advantages, calling external LLM judges at each step, or computing intrinsic rewards that require ground-truth answers at every evaluation—introduce significant costs or practical constraints. We hypothesize that internal correctness probing over LLM hidden states can be repurposed as a step-level reward signal, potentially addressing all of these limitations at once. However, existing probing research assumes clean inputs, and we first show that this assumption breaks down in multi-step settings: hidden-state probes degrade severely under prefix contamination—tracking coherence with the (possibly corrupted) prefix rather than grounded correctness—while attention-based features remain robust to contamination but underperform on clean prefixes. Building on this complementary relationship, we propose the Prefix-Aware Internal Reward (PAIR)—a two-stage model with a frozen hidden-state probe estimating belief-consistency and a lightweight attention-based head correcting it toward grounded correctness. Experimental results show that PAIR achieves the highest AUROC on contaminated trajectories while operating at negligible inference cost, enabling dense step-level reward signals for GRPO training without external model calls, ground-truth dependencies, or full-trajectory rollouts.

Poster
PACE: Geometry-Aware Bridge Transport for Single-Cell Trajectory Inference

Chenglei Yu, Chuanrui Wang, Bangyan Liao, Tailin Wu

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Single-cell trajectory inference from destructive time-course snapshots is fundamentally ill-posed: neither cross-time cell correspondences nor the continuous paths between snapshots are observed, so the observed snapshot distributions alone do not uniquely determine the underlying dynamics. Existing optimal transport and flow-based methods typically couple cells by Euclidean proximity at observed clock times, which can misalign trajectories when development is asynchronous and cells sampled at the same experimental time occupy different latent pseudotime stages. We propose PACE, a trajectory inference framework that selects geometry-consistent continuous transport dynamics from destructive time-course snapshots through three coupled components. First, PACE constructs a state- and time-dependent anisotropic Riemannian metric that preserves low cost along locally supported tangent directions while penalizing normal velocity components. Second, it alternates between refining cross-time couplings under the induced path-action cost and fitting endpoint-preserving neural bridges between adjacent snapshots. Third, it distills the learned bridge dynamics into a global continuous-time velocity field over cellular states. Across seven controlled and biological datasets covering nine held-out reconstruction experiments, PACE achieves the strongest overall reconstruction performance, reducing MMD, $\mathcal{W}_1$, and $\mathcal{W}_2$ by 23.7\% on average relative to the strongest competing baseline. PACE also improves RNA-velocity alignment by 15.4\% on an embryoid body differentiation benchmark, without requiring explicit cell pairing, lineage tracing, or RNA velocity supervision during training. Code is available at \url{https://anonymous.4open.science/r/PACE-F444/}.

Poster
Overcoming the Resolution Limit: Significance-Aware Regularization for Intersectional Fairness

Antonio Ferrara, André Panisson, Francesco Cozzi, Alan Perotti, Francesco Bonchi

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Intersectional fairness requires evaluating models across fine-grained subgroups. However, as group definitions become more granular, the sample size per subgroup shrinks, causing fairness estimates to become increasingly unstable. Existing in-processing methods are _certainty-blind_: they penalize observed disparities without distinguishing statistically certified unfairness from sampling noise. This leads to _fairness overfitting_, where models sacrifice utility to "fix" spurious disparities in sparse regimes. To address this, we introduce the _significant-excess_ metric family, a continuous, uncertainty-aware fairness score that measures only the portion of a subgroup’s disparity exceeding what sampling variation can explain at a specific confidence level. Leveraging this, we propose SAFER (Significance-Aware Fairness Regularizer), a differentiable in-processing method that gates fairness penalties using a soft-count likelihood-ratio significance test. SAFER satisfies a _provable safety property_: when no subgroup disparity is statistically certifiable, its fairness gradient is exponentially small and training reduces to unconstrained optimization. Mechanism ablations across three benchmark datasets and purpose-built stress variants confirm that each component of SAFER – threshold smoothing, the significance gate, and a dense-tail term – is empirically necessary in its theoretically predicted operating regime. SAFER consistently achieves a superior fairness-utility Pareto frontier, compared to baselines methods in sparse intersectional settings while preserving utility when certified unfairness is absent.

Poster