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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Adaptive Gated Simplicial Propagation for Node Classification in Multimodal Graphs

Linlin Ye, FangFang Li, Huihui Zhang, Lincheng Jiang, Wei Wu

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Node classification in multimodal graphs plays an important role in many real-world applications, where nodes are described by multiple modalities such as text and images, and the graph structure captures relations among entities. However, most existing Graph Neural Networks (GNNs) still focus on pairwise connections, overlooking higher-order relational patterns. Recent studies have explored simplicial complexes to capture higher-order interactions and integrated them into GNN frameworks. Motivated by this line of work, we propose Adaptive Gated Simplicial Propagation (AGSP), an end-to-end framework for node classification in multimodal graphs. Specifically, AGSP first introduces a simplicial propagation layer to capture higher-order relations beyond pairwise connections; then it applies an adaptive gating mechanism to balance multi-order topological relations, enhancing the discriminative ability of node classification. Extensive experiments validate that AGSP generally outperforms the state-of-the-art baselines, highlighting the effectiveness of combining multimodal information with higher-order graph topology through adaptive gated fusion.

Poster
Adaptive Fine-Tuning Scheduler for Multi-Tenant Edge LLM via Convergence-Aware Bandits

Yandi Li, Jianxiong Guo, Yupeng Li, Zhiqing Tang, Tian Wang, Weijia Jia

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Personalizing Large Language Models (LLMs) directly on local edge servers is becoming increasingly important for privacy-preserving and context-aware applications. However, this potential is bottlenecked by hardware resources: limited GPU memory permits only a fixed number of train-ready LoRA adapters, while compute constraints enforce sequential fine-tuning updates. This creates a critical challenge: scheduling scarce update opportunities across a dynamic stream of resident tenants to improve overall model quality and scheduling stability. Crucially, standard Multi-Armed Bandit (MAB) algorithms fail to distinguish between low-potential tenant streams and fully saturated adapters, leading to wasteful exploration on tasks that offer little further gain. To address this, we propose WCA-UCB (Windowed Convergence-Aware UCB), a scheduler designed for this piecewise-converging non-stationary environment. By formally modeling fine-tuning as a slot-constrained bandit problem with piecewise-converging rewards, WCA-UCB detects when an adapter has saturated to pause its training and resets stale statistics after tenant replacement or harmful drift. We prove a dynamic regret bound of $\tilde{O}(\log T)$ and validate the system on an edge-like single-GPU LoRA prototype running Qwen2.5-1.5B. Results demonstrate that WCA-UCB reduces model perplexity by $2.6$% to $8.6$% and uses up to $5.8\times$ fewer training-target switches than strong non-stationary baselines. These results highlight the necessity of convergence-aware scheduling for scalable local LLM personalization.

Poster
Adaptive Feature Propagation for Attribute-Missing Graph Clustering

Xiang Long, Qianqian Wang

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Attribute-Missing Graph Clustering (AMGC) is a critical yet challenging task in real-world applications, in which only a subset of nodes hold complete attributes information while others are partially missing. Though existing feature propagation-based methods can effectively recover missing node attributes, they commonly assume uniform contributions across all nodes, ignoring unreliable nodes that may degrade imputation quality. Furthermore, adopting low-pass graph filters often suffers from the over-smoothing problem and inevitably sacrifices discriminative information. %Besides, traditional contrastive learning pulls all the node embeddings evenly, which might conflict with the rule that intra-cluster nodes should be closer to each other. To address these limitations, we propose \underline{\textbf{A}}daptive \underline{\textbf{F}}eature \underline{\textbf{P}}ropagation (AFP) for attribute-missing graph clustering. Specifically, we first design a reliability-aware feature propagation mechanism that adaptively weights edges based on node importance. Then, we introduce a multi-scale embedding module to capture both local and global structural information. Finally, we develop a topology-aware contrastive loss to enhance clustering consistency. Extensive experiments on benchmark datasets demonstrate the superiority of our method.

Poster
Adaptive Delayed-Update Cyclic Algorithm for Variational Inequalities

Yi Wei, Xufeng Cai, Jelena Diakonikolas

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Cyclic block coordinate methods are widely used in practice for their simplicity and strong empirical performance. Yet, their theoretical behavior is challenging to explain, and setting their step sizes$-$beyond classical coordinate descent for minimization$-$requires careful tuning or line-search machinery. In this work, we develop $\texttt{ADUCA}$ (Adaptive Delayed-Update Cyclic Algorithm), a cyclic algorithm addressing a broad class of Minty variational inequalities with monotone Lipschitz operators. $\texttt{ADUCA}$ is parameter-free and locally adaptive: it requires no global or block-wise Lipschitz constants, it uses no per-epoch line search, and it adapts to local problem geometry. A key feature of the algorithm is using operator information delayed by a full cycle, which makes the algorithm compatible with parallel and distributed implementations, and attractive due to weakened synchronization requirements across blocks. We prove that $\texttt{ADUCA}$ attains (near) optimal global oracle complexity as a function of target error $\epsilon >0$, scaling with $1/\epsilon$ for monotone operators, or with $\log^2(1/\epsilon)$ for operators that are strongly monotone.

Poster
Adaptive Covariance and Multi-Layer Alignment for Out-of-Distribution Detection

Haoyang Su, Qi Chen, Max Gutbrod, Johan Verjans, Zhibin Liao

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Out-of-distribution (OOD) detection plays a pivotal role in ensuring the reliability and trustworthiness of AI systems. Although existing approaches achieve strong performance by leveraging features, logits, or both, most of them cannot generalize well across domains due to either overlooking critical information in low-level representations from shallow layers or utilizing sub-optimal layer selection strategies. In this paper, we propose Multi-Layer Adaptive Mahalanobis-Cosine Similarity (ML-AMCoS), a method that adaptively integrates cosine similarity with class-conditional Gaussian distributions. ML-AMCoS is designed to capture subtle nuances in feature covariance when intra-class variance is low, while suppressing covariance noise when the variance is high. To optimize the utilization of each layer, we calculate contribution weights based on performance against pseudo-OOD samples, which are generated by cut-mixing in-distribution (ID) training images with the four corners of images from different classes. Extensive experiments across diverse domains demonstrate that our method significantly improves robustness and detection accuracy, achieving an average AUROC of 81.13\% and FPR@95 of 40.12\% on near-OOD detection, outperforming the state-of-the-art methods by 7.25\% and 7.08\%, respectively.

Poster
Adaptive Conditional Gradient Sliding: Projection-Free and Line-Search-Free Acceleration

Shota Takahashi

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We study convex optimization problems over a compact convex set where projections are expensive but a linear minimization oracle (LMO) is available. We propose the *adaptive conditional gradient sliding method* (AdCGS), a projection-free and line-search-free method that retains Nesterov's acceleration with adaptive stepsizes based on local Lipschitz estimates. AdCGS combines an accelerated outer scheme with an LMO-based inner routine. It reuses gradients across multiple LMO calls to reduce gradient evaluations, while controlling the subproblem inexactness via a prescribed accuracy level coupled with adaptive stepsizes. We prove accelerated rates for convex objective functions, matching projection-based methods, without relying on a projection oracle. For locally strongly convex objective functions, we further establish linear convergence without additional geometric assumptions on the constraint set, such as polytopes or strongly convex sets. Experiments on constrained $\ell_p$ regression, logistic regression, and least-squares problems demonstrate that AdCGS improves over projection-free baselines and provides competitive performance when projections are inexpensive.

Poster
Adaptive Communication Range for Scalable Cooperative Multi-Agent Reinforcement Learning

Huizhong Song, Wei Wei, Lin Li, Lijun Zhang, Fengjiao Li

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Cooperative multi-agent reinforcement learning (MARL) has long faced scalability challenges due to the exponential growth of the state-action space as the number of agents increases. Existing methods typically enhance scalability by filtering out communications with low-relevance agents. However, such filtering often relies on global state and fixed graph distribution, limiting adaptability in large-scale, communication-constrained environments. In this paper, we propose a scalable MARL method, called Adaptive Communication Range PPO (ACR-PPO), that decomposes the decision-making under communication budget constraints as a sequential process: a communication policy first selects each agent’s communication range within a given budget, followed by a behavior policy that conditions actions on the resulting neighborhood observations. More importantly, we provide a theoretical guarantee of monotonic performance improvement under communication budget constraints. Experiments across diverse scenarios demonstrate that ACR-PPO preserves policy performance while significantly reducing communication costs through adaptive range control.

Poster
Adaptive Calibration in Non-Stationary Environments

Junyan Liu, Haipeng Luo, Lillian Ratliff

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Making calibrated online predictions is a central challenge in modern AI systems. Much of the existing literature focuses on fully adversarial environments where outcomes may be arbitrary, leading to conservative algorithms that can perform suboptimally in more benign settings, such as when outcomes are nearly stationary. This gap raises a natural question: can we design online prediction algorithms whose calibration error automatically adapts to the degree of non-stationarity in the environment, smoothly interpolating between i.i.d. and adversarial regimes? We answer this question in the affirmative and develop a suite of algorithms that achieve adaptive calibration guarantees under multiple calibration measures. Specifically, with $T$ being the number of rounds and $C\in[0,T]$ being an unknown non-stationary measure defined as the minimal $\ell_1$ deviation of the mean outcomes, our algorithms attain $\widetilde{O}(\sqrt{T}+(TC)^{\frac{1}{3}})$ for $\ell_1$ calibration error and $\widetilde{O}((1+C)^{\frac{1}{3}})$ for both $\ell_2$ and pseudo KL calibration error. These bounds match the optimal rates in the stationary case ($C=0$) and recover known guarantees in the fully adversarial regime ($C=T$). Our approach builds on and extends prior work [Hu et al., 2025, Luo et al., 2025], introducing an epoch-based scheduling together with a novel non-uniform partition of the prediction space that allocates finer resolution near the underlying ground truth.

Poster
Adaptive Adversaries: A Multi-Turn, Multi-LLM Benchmark for LLM Agent Security

Devina Jain, David Hartmann, Chuan Li

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LM-based agents process external content, exposing them to prompt injection and multi-turn manipulation. Most safety benchmarks evaluate defenders against fixed attack pools collected before evaluation, single-turn or multi-turn. We present a 21-scenario benchmark for adaptive multi-round attacks against memoryless LLM defenders: an autonomous LLM attacker observes prior defender responses and pivots across rounds, while each defender response is evaluated as a fresh interaction. Holding the 21 scenarios, attackers, defenders, and structured-output scoring fixed, restricting scoring to the first attacker turn yields $0$--$1%$ attack success rate (ASR); allowing 15 rounds of adaptive attack yields $8.3$--$19.0%$. Pooling three frontier attacker LLMs uncovers up to $2.4\times$ as many unique successful attacks as the best single attacker, and the generated attacks have low cosine similarity ($0.02$--$0.14$) to attacks in existing benchmarks. Claude Opus 4.6 and GPT-5.4 are aggregate-equivalent ($8.3%$ vs. $11.1%$ ASR), but their weaknesses differ sharply: on one scenario Opus reaches $60%$ ASR ($95%$ CI $36$--$80%$) while GPT-5.4 and Gemini each stay at $7%$ (CI $1$--$30%$). $15$ of $21$ scenarios distinguish at least one defender pair, yet rankings disagree across scenarios (Kendall's $W = 0.21$). We release the benchmark---21 evaluation scenarios, 10 public development scenarios, the orchestrator, baseline harnesses, and a multi-attacker CLI---plus 945 transcripts from the $3\times3$ frontier matrix, an attack-replay dataset, and $18{,}422$ battles from an open competition's final scoring rounds.

Poster
Adapting to Conflict: Equilibrium Structure and Adaptive Learning in Harmonic Games

Davide Legacci, Panayotis Mertikopoulos, Bary Pradelski

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Zero-sum games are the textbook model of strategic competition—yet they can fail to capture conflict even in simple settings. *Harmonic games* provide a more robust framework for opposed interests: they are invariant under strategic equivalence, and naturally extend beyond pairwise competition. This generality comes at a structural cost. We show that, in odd-dimensional harmonic games, the set of totally mixed Nash equilibria is a generically non-convex real algebraic variety of dimension at least one, extending to the boundary of the strategy space. As a result, learning becomes delicate: although finely tuned methods are known, whether adaptive, parameter-agnostic learning is possible has remained open. We resolve this question in the affirmative. We introduce a flexible extrapolation-based variant of follow-the-regularized-leader (FTRL+) that converges to Nash equilibrium while achieving order-optimal regret: $\mathcal{O}(1)$ in self-play and $\mathcal{O}(\sqrt{T})$ against arbitrary opponents. The method is fully adaptive—each player updates from locally observable information alone, without access to global problem parameters or shared signals—yielding the first parameter-agnostic learning dynamics provably convergent in this class.

Poster
Adapting in the Dark: Efficient and Stable Test-Time Adaptation for Black-Box Models

Yunbei Zhang, Shuaicheng Niu, Chengyi Cai, Feng Liu, Jihun Hamm

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Test-Time Adaptation (TTA) for black-box models accessible only via APIs remains a largely unexplored challenge. Existing approaches such as post-hoc output refinement offer limited adaptive capacity, while Zeroth-Order Optimization (ZOO) enables input-space adaptation but faces high query costs and optimization challenges in the unsupervised TTA setting. We introduce BETA (Black-box Efficient Test-time Adaptation), a framework that addresses these limitations by employing a lightweight, local white-box steering model to create a tractable gradient pathway. Through a prediction harmonization technique combined with consistency regularization and prompt learning-oriented filtering, BETA enables stable adaptation with no additional API calls and negligible latency beyond standard inference. BETA achieves a +7.1% accuracy gain on ViT-B/16 (ImageNet-C) and +3.4% on CLIP (ImageNet-S/R), surpassing strong white-box and gray-box methods including TENT and TPT. On a commercial API, BETA achieves comparable performance to ZOO at 250x lower cost while maintaining real-time inference speed, establishing it as a practical and efficient solution for real-world black-box TTA.

Poster
Adapting Vision Transformers to Organoid Imaging

Yu Takagi

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Organoids are an increasingly central scientific platform for drug screening, disease modeling, and regenerative medicine. Because organoid form is closely tied to function, AI-driven image analysis has drawn intense interest, yet every existing organoid imaging study evaluates representations on a single dataset and no work has quantitatively compared representations across the breadth of public organoid datasets. We close this gap with \textbf{OrgBench}, a benchmark of 12 vision foundation models (VFMs) on 13 public organoid-imaging datasets spanning detection, segmentation, classification, and temporal outcome prediction. The benchmark reveals a structured domain gap: task-family winners shift across the benchmark and parameter count is a poor predictor of transfer. Building on this, we introduce \textbf{OrgFM}, a small bottleneck adapter that we continually pre-train on unlabeled organoid images while keeping a general-purpose vision transformer frozen. On the OrgBench task-family aggregates, OrgFM improves over its frozen base backbone. Layer- and feature-level interventions localize the gains to a small set of late-layer morphology-sensitive features: the adapter sparsely supplements, rather than replaces, the base representation. Together, this is the first cross-task, cross-backbone study of organoid imaging at scale; the OrgBench/OrgFM pairing establishes that the parameter-efficient adapter direction is a promising path for organoid representations and clarifies why it works.

Poster
AdaptNC: Adaptive Nonconformity Scores for Conformal Prediction under Distribution Shift

Renukanandan Tumu, Aditya Singh, Rahul Mangharam

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Rigorous uncertainty quantification is essential for the safe deployment of autonomous systems in unconstrained environments. Conformal Prediction (CP) provides a distribution-free framework for this task, yet its standard formulations rely on exchangeability assumptions that are violated by the distribution shifts inherent in real-world robotics. Existing online CP methods maintain target coverage by adaptively scaling the conformal threshold, but typically employ a static nonconformity score function. We show that this fixed geometry leads to highly conservative, volume-inefficient prediction regions when environments undergo structural shifts. To address this, we propose \textbf{AdaptNC}, a framework for the joint online adaptation of both the nonconformity score parameters and the conformal threshold. AdaptNC leverages an adaptive reweighting scheme to optimize score functions, and introduces a replay buffer mechanism to mitigate the coverage instability that occurs during score transitions. We evaluate AdaptNC on diverse robotic benchmarks involving multi-agent policy changes, environmental changes and sensor degradation. Our results demonstrate that AdaptNC significantly reduces prediction region volume compared to state-of-the-art threshold-only baselines while maintaining target coverage levels.

Poster
AdaptFlow: State-Anchored Goal Conditioning with Flow Matching for Offline Goal-Conditioned RL

Jaeseok Joo, Insoon Yang

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Offline goal-conditioned reinforcement learning (GCRL) aims to learn a single policy that adapts its behavior to arbitrary goals from a fixed dataset, making injection of the goal information into the policy a central design question. While recent works increasingly leverage expressive conditional generative modeling architectures, which have demonstrated remarkable success in computer vision, architectural choices for goal conditioning in offline GCRL remain under-explored. We identify that goals in GCRL differ from typical conditioning signals in two ways: they are often noisy or redundant, and they are consumed within a time-sequential episode where the relevant context of a fixed goal shifts as the agent's state evolves. Motivated by these observations, we propose State-Anchored Goal Conditioning (SAGC), a modulation-based goal conditioning scheme that derives its scale and shift parameters by jointly processing state and goal representations in a learned latent space. We further introduce AdaptFlow, an end-to-end trainable offline GCRL architecture that integrates conditional flow matching with SAGC. AdaptFlow outperforms matches all baselines on 23 out of 27 OGBench tasks.

Poster
AdapMatch: Adaptive Bias Decoupling for Semi-Supervised Partial Label Learning under Unknown Class Distributions

Yuheng Jia, Yaodong Shen, Jiahao Jiang, Hui Liu, Junhui Hou

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Partial Label Learning (PLL) trains models from instances with candidate label sets containing the ground-truth, while Semi-Supervised Partial Label Learning (SSPLL) further leverages the available unlabeled data to prompt the performance. The previous SSPLL methods implicitly assume the unlabeled data are class-balanced distributed. However, in realistic scenarios, the class distribution of unlabeled data is unknown, resulting in performance collapse on minority classes for the existing SSPLL methods. We identify two coupled biases behind this failure: (i) pseudo-label selection bias, where high-confidence filtering tends to over-select samples from dominant classes, causing the training data to become increasingly skewed toward these classes; and (ii) disambiguation bias, where dominant classes are more likely to win within candidate sets, even when they are incorrect. Theoretically, we show that these two biases reinforce each other over training, forming a feedback loop that degrades generalization performance. To weaken this loop, we propose AdapMatch, which uses DAS to reduce the skew in training data caused by pseudo-label selection bias via prior-aware pseudo-label admission and CAD to lower the disambiguation error by suppressing candidate-set domination. Across five benchmarks, AdapMatch yields gains up to 41.31\% at most , showing strong robustness to varying scale, imbalance, and ambiguity. The code is available at \url{https://anonymous.4open.science/r/AdapMatch-8BC5}.

Poster
AdaWM: Few-Shot Adaptation of World Models to Unseen Dynamical Regimes

Zian Guan, Guozheng Li, Zilun Zhang, Zecong Tang

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World models predict future states from observations and actions, enabling planning and decision-making in complex environments. Most existing approaches assume fixed environment dynamics and struggle to generalize to unseen regimes without retraining. However, in many real-world multi-agent systems, environment dynamics vary across scenarios due to diverse styles and evolving agent behaviors. Meanwhile, only a small number of demonstration transitions are available in new environments, making adaptation to such unseen dynamical regimes challenging. In this work, we introduce AdaWM, a world model that achieves zero-gradient few-shot adaptation to unseen dynamical regimes through Feature-wise Linear Modulation (FiLM). AdaWM is built on a JEPA-style latent prediction framework with a permutation-invariant context encoder whose output modulates the model through FiLM, enabling fast adaptation without modifying model parameters. Across heterogeneous multi-agent environments, AdaWM consistently reduces prediction error under distribution shift, outperforming fine-tuning and MAML in both adaptation gain and efficiency. Specifically, it achieves up to 15% reduction in prediction error with only K=5 demonstrations. Moreover, we reveal that scaling model capacity alone does not guarantee effective adaptation: fine-tuning a JEPA-based model with 3.9× more parameters degrades performance by 40%, highlighting the importance of explicit conditioning mechanisms over scale alone. These results show that AdaWM provides an effective approach for adapting world models to novel dynamical regimes.

Poster
AdaTree: Serving-Aware Adaptive Tree Construction for Speculative Decoding

Soohyun Cha, Jungi Lee, Jaewoong Sim

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Speculative decoding accelerates generative inference of large language models (LLMs) by using a small draft model to propose multiple candidate tokens, which are then verified in parallel with the target model in a single decoding iteration. While the state-of-the-art method of tree-based speculative decoding helps improve generation throughput over non-speculative inference, deploying it in LLM serving systems often yields suboptimal performance due to dynamically changing serving conditions. In particular, our analysis shows that the optimal tree configuration---the one that maximizes performance---varies with two key serving conditions: request rate and per-request characteristics. Based on the analysis, we present AdaTree, a plug-in component for LLM serving systems that dynamically adapts tree configurations to varying serving conditions. AdaTree predicts model execution time and acceptance length across different tree configurations and selects the one that maximizes speculative decoding efficiency. To capture the non-linear relationship between tree configuration and model execution time, AdaTree employs decision trees as its core modeling primitive. Our evaluation shows that AdaTree consistently outperforms both chain-based and static tree-based speculative decoding across diverse serving conditions.

Poster
AdaState: Self-Evolving Anchors for Streaming Video Generation

Yusuf Dalva, Pinar Yanardag

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Autoregressive video diffusion models generate streaming video by producing frames sequentially, conditioning each chunk on previously generated content. These models are structurally anchored to the first frame: its key-value representation occupies a privileged position in the attention cache and serves as the primary scene reference throughout generation. As the cleanest and most error-free position in the cache, this anchor draws disproportionate attention, suppressing video dynamics, and locking scene composition to the initial viewpoint even as the scene naturally evolves. The result is a temporally shallow video in which motion, camera movement, and scene progression are dampened in favor of static consistency. To address this, we replace the static anchor with an adaptive state, a hidden latent that the model denoises alongside content at every chunk but never generates. Rather than referencing a frozen first frame, the model generates its own scene anchor at each step by attending to both the previous state and the current content, producing a reference that evolves with the generated content. Unlike standard video generation, which encodes an absolute notion of time, our formulation treats time as relative: every generation step sees the same positional structure regardless of how far generation has progressed, and the state transition is identical at every chunk. Together, these properties introduce a recurrence into the generation process, where denoising serves as the transition function, and the KV cache serves as the carrier, requiring no external module. Experiments demonstrate that the adaptive state substantially improves video dynamics, enabling richer motion and natural scene progression within generated videos.

Poster
AdaST: Adaptive Coupling for Spatial-Temporal Forecasting

Zhenyu Lei, Chenghao Liu, Yushun Dong, Ryan Qi Wang, Jundong Li

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Spatial-temporal (ST) forecasting underpins many real-world systems such as traffic, climate, and energy networks. While existing methods implicitly assume strong spatiotemporal coupling, we observe that real-world ST data exhibits distinct coupling regimes, ranging from temporal-dominated and spatial-dominated to strongly coupled patterns. This mismatch causes current models to suffer from spurious dependencies and degraded performance when one correlation dominates. To overcome this limitation, we aim to dynamically modulate spatial and temporal modeling based on the data's inherent coupling structure. However, three key challenges exist: unknown coupling structure, heterogeneous coupling dynamics, and suboptimal spatial modeling. We propose AdaST, an adaptive ST forecasting framework that tackles these challenges through a decompose-recompose paradigm. AdaST factorizes inputs into components capturing different coupling patterns using heterogeneity-aware experts. Each component is processed by role-aligned modules, and a correlation-informed adaptive recomposer integrates them for final prediction. Extensive experiments confirm that AdaST significantly outperforms state-of-the-art baselines, validating the necessity of an adaptive approach.

Poster
AdaPreLoRA: Adafactor Preconditioned Low-Rank Adaptation

Ziyun Liu, Fengmiao Bian, Jian-Feng Cai

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Low-Rank Adaptation (LoRA) reparameterizes a weight update as a product of two low-rank factors, but the Jacobian $J\_\mathcal{G}$ of the generator mapping the factors to the weight matrix is rank-deficient, so the factor-space preconditioner $J\_\mathcal{G}^\* \mathcal{F}\_t J\_\mathcal{G}$ induced by any ${W}$-space preconditioner $\mathcal{F}\_t$ is singular, and consequently the standard chain rule cannot be uniquely inverted to map a preconditioned ${W}$-space direction back to a factor-space update. We cast existing LoRA optimizers in a unified framework parameterized by two choices: (i) which invertible surrogate for $J\_\mathcal{G}^\* \mathcal{F}\_t J\_\mathcal{G}$ to use, and (ii) which $\mathcal{F}\_t$ on ${W}$ to use. Existing methods occupy four families along these axes: factor-space adaptive updates, block-diagonal surrogates for $J\_\mathcal{G}^\* J\_\mathcal{G}$, Frobenius-residual pseudoinverse methods, and Riemannian manifold constraint. Within this design space, a gradient-statistics-aware $\mathcal{F}\_t$ paired with a closed-form factor-space solve at $\mathcal{O}((m+n)r)$ memory remains underexplored. We propose AdaPreLoRA, which fills this gap by adopting the Adafactor diagonal Kronecker preconditioner $\mathcal{H}\_t$ on ${W}$ and selecting from the resulting factor-space solution family the element minimizing an $\mathcal{H}\_t$-weighted imbalance between the two factor contributions; by construction, the resulting factor update is the closest LoRA approximation to the preconditioned ${W}$-space direction under the $\mathcal{H}\_t$-weighted norm. Across GPT-2 (E2E), Mistral-7B and Qwen2-7B (GLUE, ARC, GSM8K), and diffusion-model personalization, AdaPreLoRA is competitive with or improves over a representative set of LoRA optimizers while keeping peak GPU memory at the LoRA optimizer level.

Poster