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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Decision-Focused Learning in MDPs: An Occupancy Measure Approach

Zihao Zhao, Ashwath K Karunakaram, Ali Eshragh, Yuexing Li, Kai Wang

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In this work, we consider decision-focused learning (DFL) for a Markov decision process (MDP), where existing methods differentiate through the KKT conditions of the Bellman equation and require solving a linear system over all state-action pairs, limiting its scalability. We address this by reformulating the MDP as an occupancy measure-based linear program (LP), whose feasible region is induced by predicted dynamics, and we derive a closed-form gradient by identifying the active constraints in the feasible polyhedron via the pivoting algorithm. This occupancy measure-based LP layer raises two challenges: (1) LP's solution gradient is discontinuous when active constraints change, and (2) the LP backward cost still scales with the state size, which is costly for large or continuous state spaces. We address the challenges with an augmented Lagrangian surrogate and smooth the boundary jumps by random row sketching of the constraints, and a learnable soft state-aggregation layer and its function-approximation generalization that scales the LP to large finite and continuous-state MDPs. Across multiple tasks, our methods reach lower regret than KKT-based DFL and two-stage baselines with significantly lower computation cost. The source code for all experiments is available [here](https://anonymous.4open.science/r/State_Aggregation_Project-3E64/).

Poster
Decision-Aware Proximal Bridge Learning for Optimal Treatment Selection

Tomas Garriga, Alejandro Almodóvar, Axel Brando, Gerard Sanz, Eduard Serrahima de Cambra, Juan Parras

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Individualized treatment selection with continuous actions requires accurate causal response estimation in decision-relevant regions, rather than uniformly over the entire action space. Estimating a global causal response surface and then choosing the treatment that maximizes it can therefore be suboptimal, since standard estimation objectives allocate modeling effort according to the observed treatment distribution rather than the regions that determine the optimal decision. While decision-aware approaches have been studied in unconfounded settings, this problem remains underexplored in proximal causal inference, where proxy variables and bridge functions enable identification under suitable assumptions even in the presence of hidden confounding. Despite recent progress, proximal methods have primarily focused on treatment-effect and potential-outcome estimation rather than treatment selection and optimal decision-making. To bridge this gap, we introduce a policy-targeted weighted bridge loss that emphasizes decision-relevant treatment regions while retaining global stabilization. We prove a regret bound showing that the proposed weighted bridge loss controls treatment-selection regret through a weighted ill-posedness constant. We instantiate the framework in decision-aware variants of several proximal bridge solvers, yielding practical algorithms that alternate between weighted bridge estimation, response-surface projection, policy update, and weight refinement. Empirically, we find that decision-aware weighting reduces regret across several bridge solvers, suggesting improved treatment selection in proximal settings.

Poster
Decision Path Tracing for Causal Analysis in Transformers

Won Jo, Dahee Kwon, Jongeun Baek, Cheongwoong Kang, Jaesik Choi

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Investigating the causal structures of transformers often entails a trade-off between the granularity of the explanation and computational overhead. Existing approaches either bypass the full internal chain, potentially missing critical decision-relevant links, or struggle with the combinatorial explosion of path enumeration. To address these challenges, we propose an efficient automated path-tracing method that ensures both causal reliability and algorithmic feasibility. Through extensive verification, we find that (i) the identified paths are the primary sources for decision signals, as evidenced by a marked decrease in self-repair compared to non-path components; and (ii) transformers utilize modular, class-shared path mechanisms to process categorical information. Beyond these findings, we show that the potential implications of our method can stem from sparse manipulation, highlighting efficient applicability to downstream tasks such as model debugging and pruning.

Poster
Decision Focused Scenario Learning for Contextual Stochastic Programming

Jonathan Hornewall, Tito Homem-De-Mello, Vincent Leclere

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Decision-focused scenario learning for contextual two-stage stochastic programming has emerged as a promising research direction, but open questions remain. A general theory for when scenario generators can yield optimal decision policies is currently lacking. Many existing methods require strict assumptions on which second-stage data are allowed to be random. Generally, the non-differentiability of the decision-focused objective is a source of difficulty. This paper makes three theoretical contributions, each aiming to remedy one of these challenges. First, we present a comprehensive theory for when scenario generators can induce optimal policies, showing that learning a single out-of-support scenario component is often sufficient. Second, we demonstrate a theoretical and methodological equivalence result between learning different second-stage data components, relaxing assumptions required for applying existing methods. Third, we study log-barrier smoothing enabled training, presenting representability and optimization results. Finally, leveraging the theory, we propose a novel method inspired by interior-point methods from classical optimization, and validate it on standard benchmarks.

Poster
Deceptive Grounding: Entity Attribution Failure in Clinical Retrieval-Augmented Generation

Cedric Caruzzo, Donggeun Yoo, Tae Soo Kim

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Retrieval-augmented generation evaluation checks whether model claims are factually grounded in retrieved documents. It does not check whether retrieved evidence is attributed to the correct entity. A clinical RAG response can pass every automated check (zero hallucinations, near-perfect faithfulness, real citations) while presenting drug $Y$'s clinical evidence as evidence about queried drug $X$. We term this **deceptive grounding** (DG): a failure invisible to faithfulness, hallucination, and citation checks because every claim is sourced from a real document, about the wrong entity. Using a controlled factorial benchmark across 13 models, we find DG rates spanning 8--87\% at peak adversarial conditions. Medical and biomedical fine-tuned models reach up to 86.7\%; domain specialization amplifies the failure rather than mitigating it. A controlled ablation identifies the mechanism: removing entity-specific clinical evidence from retrieved documents eliminates entity-attribution failure entirely, shifting all failures to confabulation. The two failure modes respond to the same trigger, taking different paths. Production measurement across 740 drug--disease pairs finds 7.8\% overall DG in a deployed RAG system, rising to 13.6\% for recently approved drugs. Entity-attribution verification (checking that cited evidence applies to the queried entity) detects DG at 92.3\% precision and 95.8\% DG recall; no existing framework implements it.

Poster
Decentralized Q-Learning in Markov Potential Games

Onur Ünlü, Eilyan Bitar, Francesca Parise

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We propose a fully decentralized $Q$-learning dynamic for infinite-horizon discounted Markov potential games in which agents observe the global state and their own realized payoffs, but do not know the reward functions, the transition probabilities, the potential function, or the policies and the actions of the other players. In the proposed dynamic each player maintains a local estimate of its continuation payoff for each state and action and updates its policy through a smoothed best response. Importantly, the smoothing parameter is adjusted by using an online estimate of the discounted state-visitation distribution, so that players explore more in rarely visited states while exploitation is encouraged in states that are frequently visited. We prove that the induced policy sequence converges almost surely to a set of approximate Nash equilibria of the Markov potential game, with an approximation guarantee that depends only on easily computable parameters. We illustrate the performance of the proposed learning dynamic via numerical experiments on a routing game and compare it with existing independent learning schemes based on persistent $\theta$-greedy exploration.

Poster
Decentralized Multi-Goal Multi-Agent Pathfinding with Spatial Prior and Neighbor Intent Prediction

Xuening Wang, Bin Wang, Yucen Gao, Sihui Li, Xiaochun Yang

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As a variant of the Multi-Agent Pathfinding (MAPF) problem, Multi-Goal Multi-Agent Pathfinding (MG-MAPF) requires planning conflict-free paths for a team of agents to visit sequences of preassigned goal vertices. Existing search-based methods suffer from poor scalability due to their reliance on centralized control, while decentralized learning-based approaches struggle with long-horizon planning under partial observability. Furthermore, existing paradigms rarely address joint goal ordering across agents, where uncoordinated goal sequences cause multiple agents to simultaneously converge on the same region, increasing congestion and conflicts. To address these challenges, we propose the Intent-aware Multi-Goal Multi-Agent Pathfinding (IMMP), a hierarchical framework for decentralized MG-MAPF that explicitly models spatial congestion at the high level and neighbor intent at the execution level. The high-level planner encodes a spatial prior via spatially-balanced goal ordering and path planning, reducing conflict pressure passed to the low-level policy. The low-level module resolves real-time conflicts via a reinforcement learning policy augmented with a neighbor intent prediction module, trained end-to-end through a prediction-guided collaborative proximal policy optimization. Extensive experiments demonstrate that IMMP achieves strong scalability and generalization, Extensive experiments demonstrate that IMMP achieves strong scalability and generalization, reducing SoC by an average of 19.77\% compared to the best-performing decentralized baseline, while maintaining robust performance. Our code is available at https://anonymous.4open.science/r/IMMP-CB2E/

Poster
Decentralized Coupled Representation Learning

Zilin Li, Weiwei Xu, Xuchun Tong, Xuanbo Lu, Xuanqi Zhao, Ge Zhang

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The learning dynamics of decentralized coupled representation learning can be formulated as a non-autonomous stochastic dynamical system, yet the macroscopic behavior of the resulting system on continuous manifolds remains poorly understood. We establish three theoretical results for such coupled slow-fast dynamics. First, under a standard random geometric graph scaling regime, we prove that the infinitesimal generator of the discrete Markov process converges to the generator of an overdamped Langevin diffusion for every $f \in C^3(\mathcal{M})$. Second, under timescale separation, the stochastic parameter dynamics converge to a deterministic averaged flow that admits a row-orthogonality Lyapunov function, controlling row-space degeneracy and ruling out parameter divergence. Third, under a spectral gap condition, the row space of the averaged parameter trajectory converges to the principal eigenspace of the induced covariance matrix. Together, these results give a stochastic-approximation limit theory for the coupled regime in which Markovian sampling and local subspace learning co-evolve, showing that memoryless local interactions can induce a stable and structured macroscopic limit.

Poster
Decentralized Aggregation of LLM Predictions via Wagering Mechanisms

Yuhong Luo, David Pennock, Xintong Wang

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We propose WALLA, a decentralized mechanism for aggregating probabilistic predictions from multiple LLMs using wagering mechanisms. Each model reports a prediction and a learned wager reflecting its expected score advantage; predictions are then aggregated using wagers as weights. Our mechanism introduces a leave-one-out baseline that yields three key properties: dominant-strategy incentive compatibility under general belief structures, a best-response wager proportional to expected score advantage, and decoupling of prediction and wager optimization. We instantiate two mechanism variants trading off normality and no-arbitrage, both with bounded worst-case deficit independent of the number of participants. Experiments on QA benchmarks and a forecasting benchmark show that WALLA matches centralized baselines while simultaneously achieving advantage-weighted aggregation, uncertainty-awareness, fully decentralized learning, and incentive-compatibility guarantees.

Poster
Decentralized AI Governance Must Decouple Policy Processing from Capability Enforcement

Hasan Kassem, Christoforos Anagnostopoulos, Alejandro Aristizabal, Spyridon Bakas, Orion G Banks, Omar Benjelloun, Tian Cai, Sergen Cansiz, Davide Chicco, Patrick Foley, Showkot Hossain, Taeho Jung, Peter Kairouz, Yanchen Liu, Marco Lorenzi, Peter Mattson, Ann K Novakowski, Michael O&#x27, Connor, Holger Roth, Adrish Sannyasi, Charalampos Savvaidis, Micah Sheller, David Solooki, Dimitris Stripelis, Renato Umeton, Marc Vesin, Ray Wang, Wenbin Zhang, Mic Bowman, Alexandros Karargyris

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In this position paper, we argue that successful decentralized AI needs trustworthy, adaptive, and portable governance at scale. The ML community must adopt an architecture that cleanly separates \emph{policy processing} (the evaluation of evidence against governance requirements) from \emph{capability enforcement} (the gating of access to protected digital assets). We argue that the prevailing approach, in which each organization manages bespoke policy logic, custom-built for its infrastructure, produces fragmentation that undermines interoperability, transparency, and auditability of federated systems. Drawing on a survey of governance mechanisms in federated learning and data collaboration frameworks and on a concrete reference architecture built around community-driven policy objects, we argue that this decoupling is technically feasible and architecturally necessary and supports a broad class of decentralized AI governance settings. We further suggest that the AI community should invest in open, standardized policy abstractions rather than proliferate siloed governance solutions. We address counterarguments concerning the costs of standardization and the feasibility of universal policy languages.

Poster
Debiasing Random Oblique Projections for Subsampled OLS and Fast CUR in High Dimensions

Chengmei Niu, Sachin Garg, Michal Derezinski, Zhenyu Liao

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Random sampling is a fundamental tool in modern machine learning and numerical linear algebra for reducing the computational cost of large-scale matrix problems. Existing analyses, however, rely primarily on subspace embedding guarantees, which do *not* precisely characterize the statistical bias of *nonlinear* random oblique projections induced by sampling, which arises ubiquitously in subsampled least squares and fast low-rank approximation methods. Because (pseudo)inversion is *nonlinear*, these random oblique projections can be systematically *biased* even when the underlying sketch is unbiased, thereby introducing hidden bias into downstream least squares and low-rank approximation solutions. In this work, we develop a unified non-asymptotic theory for random oblique projections in high dimensions. We show that standard random sampling schemes generally induce a systematic statistical *bias* overlooked by classical subspace embedding-style analyses, and we propose a principled debiasing framework to correct it. We illustrate the power of the theory through two canonical applications. For subsampled least squares, we obtain sharp bias--variance characterizations, reveal previously unrecognized statistical *suboptimality* in widely used sampling schemes, and identify when debiasing yields provable improvements. For fast CUR decomposition, we develop a debiased approach with improved approximation accuracy. Numerical experiments further validate our theoretical findings.

Poster
Debiased DPO for Diffusion Models

Duc Khiem Pham, Quang Nguyen, Tung D Nguyen, Jingsen Zhu, Michele Santacatterina, Dimitris Metaxas, Ramin Zabih

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Direct Preference Optimization (DPO) enables offline alignment of diffusion models from preference pairs without explicit reward modeling, but scaling DPO requires large amounts of expensive human preference data. In this paper, we consider a semi-supervised approach where only a small subset of preference pairs is annotated by humans, while the remaining (much larger) pool is unlabeled and annotated by inexpensive synthetic feedback e.g., vision-language models scoring image pairs or self-training from the current model. However, such synthetic supervision is not a replacement for human judgments: it can be systematically misaligned, so naively mixing human and synthetic preferences will yield misaligned inference. We introduce DeDPO, a debiased objective that integrates a doubly robust estimator from causal inference into DPO to correct synthetic-label misalignment while preserving the simplicity of DPO. Experiments show improved label efficiency and robustness to synthetic labeler quality, allowing DeDPO to outperform standard DPO under the same human-label budget and to approach fully human-supervised performance, despite using four times fewer human-labeled data.

Poster
Debiased Counterfactual Generation via Flow Matching from Observations

Hugh Dance, Johnny Xi, Peter Orbanz, Benjamin Bloem-Reddy

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Estimating counterfactual distributions under interventions is central to treatment risk assessment and counterfactual generation tasks. Existing approaches model the counterfactual distribution as a standalone generative target, without exploiting its relationship to the observational data. In this work, we show that under standard assumptions, observational and counterfactual outcome distributions are tightly linked: they have identical support and tail behavior, remain statistically close under weak confounding, and share any features of high-dimensional outcomes which are invariant to confounders. These properties motivate learning counterfactual distributions not from scratch, but via a *deconfounding flow* from the observational distribution. We formulate this problem via flow-matching and derive a semiparametrically efficient estimator based on a novel efficient influence function correction. We subsequently extend our estimator to target minimal-energy flows in high-dimensions, which we show can be especially simple targets between observational and counterfactual distributions. In experiments, deconfounding flows outperform existing debiased counterfactual distribution estimators, while also mitigating known failure modes of flow-based methods.

Poster
Deadline-Constrained Dynamic Workflow Scheduling Can be Cast as a Representation Learning Problem

Ya Shen, Gang Chen, Hui Ma, Mengjie Zhang

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Deadline-Constrained Cost-Aware Dynamic Workflow Scheduling (D-CADWS) aims to minimize virtual machine (VM) rental cost while maintaining high workflow deadline satisfaction in dynamic cloud environments. The problem is challenging because the deadline impact of assigning a workflow task to a VM is not directly observable at decision time. It depends on long-horizon effects, including downstream task dependencies, VM queueing, and interactions among dynamically arriving workflows. Existing methods usually fold deadline violations into a single reward or penalty term, which obscures the distinction between action safety and action cost. In this paper, we cast D-CADWS as a representation learning problem. The core idea is to learn a deadline-aware representation that can predict, before execution, whether a candidate action is risky with respect to the current task deadline, and then use it to guide cost-efficient scheduling. Based on this idea, we propose a representation-centered deep reinforcement learning (RCDRL) method. RCDRL constructs task-level deadline supervision, trains a predictive deadline model to learn deadline-aware representations, and learns a VM-cost critic on top of this representation. The final policy follows a safe-first rule that rejects risky actions before minimizing VM cost. We further propose a two-phase training strategy to keep the learned representation aligned with the evolving policy-induced data distribution. Experiments on dynamic workflow scheduling benchmarks show that RCDRL achieves substantially lower VM cost than other state-of-the-art heuristic and DRL baselines while maintaining strong workflow deadline success.

Poster
DeGlare: Self-Supervised Specular Removal for Industrial Metallic Surfaces via Multi-Illumination Priors

Bisma Amjad, Henry Wood, William Jacobs, Andrew Mills

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In industrial machine vision, removing specular highlights is crucial for accurate surface analysis; however, existing open research remains largely confined to natural images, limiting its efficacy on highly reflective metallic surfaces. When used for zero-shot inference, these methods generate artifacts, making them unreliable for specialized industrial scenes. Since current state-of-the-art methods rely on pixel-level supervision, adapting them to novel industrial subjects is often impractical. Such adaptation requires highlight-free ground truths across hundreds of multi-view scenes, necessitating hardware-intensive cross-polarization, which is difficult to implement at scale in uncontrolled real-world settings. To address these challenges, we propose DeGlare, a flexible training framework for highlight removal in specialized industrial settings. Our approach leverages only a single-view scene by exploiting its multi-illumination observations together with a latent permutation strategy, enabling an encoder-decoder–style architecture to implicitly learn diffuse–specular decomposition. This eliminates the dependency on the burdensome manual annotation required by state-of-the-art supervised methods. We demonstrate the practical effectiveness of our approach on a real-world industrial robotic rig data set, where DeGlare achieves promising performance under limited data and annotation constraints.

Poster
DeFlowCritic: Dense Latent Reward Alignment for Text-to-Image Flow Matching Models

Zeeshan Khan, Xin Yu, Shizhe Chen, Cordelia Schmid

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Online reinforcement learning (RL) has emerged as a powerful paradigm for aligning text-to-image flow matching models with complex user intent. However, existing methods typically rely on sparse rewards computed only from final decoded images. This delays credit assignment across the denoising trajectory and makes training computationally expensive. Moreover, simply combining multiple rewards does not reliably produce a Pareto trade-off, where gains in compositional accuracy often degrade aesthetic quality. In this work, we propose \textbf{DeFlowCritic}, an efficient online RL framework based on Dense Latent Reward Alignment. Unlike prior work, our method provides dense supervision on intermediate latents, enabling early-stage guidance for the denoising trajectory. To achieve this, we introduce an internal critic that evaluates noisy latents using features extracted directly from the diffusion model, a representation inherently better suited for latent-space reward estimation than standard image encoders. We construct a high-quality reward-modeling dataset with continuous scores for critic training, jointly capturing compositional correctness and aesthetic preference. The resulting dense reward signals enable efficient online RL training and inference scaling. Experiments show that our method achieves a superior balance between prompt faithfulness and visual quality on GenEval2 and T2I-CompBench benchmarks.

Poster
DeFlow: Decoupling Behavior-Prior Modeling and Value Maximization for Offline Policy Extraction

Zhancun Mu, Chi Zhang

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We present DeFlow, a decoupled offline RL framework for extracting high-value actions from a learned multi-step flow prior. Directly optimizing iterative generative policies typically requires backpropagation through ODE solvers, while shortcut policies trade off expressivity, inference cost, and policy-improvement objectives. DeFlow keeps the flow model as a behavior prior and trains a lightweight action-conditioned residual module for value improvement under an adaptive trust-region penalty. This design bypasses solver differentiation and encourages proximity to the learned prior without treating the trust region as exact data-support preservation. Empirically, DeFlow is competitive with recent generative offline RL baselines, with the clearest gains on selected multimodal manipulation and offline-to-online settings.

Poster
DeEscalWild: A Real-World Benchmark for Automated De-Escalation Training with SLMs

Md Hasebul Hasan, Krity H Charu, Eshwara Prasad Sridhar, Shuchisnigdha Deb, Mohammad A Islam

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Effective de-escalation is critical for law enforcement safety and community trust, yet traditional training methods lack scalability and realism. While Large Language Models (LLMs) enable dynamic, open-ended simulations, their substantial computational footprint renders them impractical for deployment on the lightweight, portable hardware required for immersive field training. Small Language Models (SLMs) offer a viable real-time alternative but suffer from a critical scarcity of high-quality, domain-specific training data. To bridge this gap, we present DeEscalWild, a novel benchmark dataset curated from a multi-stage pipeline of ``in-the-wild`` police-civilian interactions extracted from publicly available video repositories. Starting with 5,000 raw inputs, we employed a rigorous hybrid filtering process combining human-in-the-loop verification with ``LLM-as-a-Judge`` evaluation to distill 1,500 high-fidelity scenarios. The resulting corpus comprises 285,887 dialogue turns, totaling approximately 4.7 million tokens. Extensive experiments demonstrate that SLMs fine-tuned on this data significantly outperform their base counterparts across ROUGE-L, BLEU-4, METEOR, BERTScore, Realism Score, and human evaluation metrics. Notably, our fine-tuned Qwen 2.5 (3B-Instruct) surpasses the general-purpose Gemini 2.5 Flash model when evaluated under equivalent conditions, demonstrating that domain-optimized SLMs can achieve superior performance with a fraction of the computational cost.This work establishes the civilian-response simulation agent and supporting dataset needed for accessible, low-latency de-escalation training at the edge. Code and dataset are available at \url{https://github.com/Hasebul/DeEscalWild-Benchmark-Framework} (code) and \url{https://doi.org/10.7910/DVN/CWMCZI} (dataset).

Poster
Dataset Distillation via Drifting

George Cazenavette, Angelina Quan, Giannis Daras, Antonio Torralba, Vincent Sitzmann

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The task of \textit{dataset distillation} aims to find a small set of synthetic images such that training a model on them reproduces the performance of the same model trained on a much larger dataset of real samples. Existing distillation methods focus on synthesizing datasets that enable training \textit{randomly initialized} models. In contrast, state-of-the-art vision approaches are increasingly building on large, pre-trained self-supervised models rather than training from scratch. In this paper, we investigate the problem of distilling datasets that enable us to optimally train \textit{linear probes} on top of such large, pre-trained vision models. We introduce a method of dataset distillation for this task called \textit{Linear Gradient Matching} that optimizes the synthetic images such that, when passed through a pre-trained feature extractor, they induce gradients in the linear classifier similar to those produced by the real data. Our method yields synthetic data that outperform all real-image baselines and, remarkably, generalize across pre-trained vision models, enabling us, for instance, to train a linear CLIP probe that performs competitively using a dataset distilled via a DINO backbone. Further, we show that our distilled datasets are exceptionally effective for fine-grained classification and provide a valuable tool for model interpretability, predicting, among other things, how similar two models' embedding spaces are under the platonic representation hypothesis or whether a model is sensitive to spurious correlations in adversarial datasets.

Poster
Dataset Collections: Challenges of Large-Scale Data Aggregation in 3D Medical Image Datasets

Yannick Kirchhoff, Saikat Roy, Elisa Stegmeier, Hamideh Haghiri, Constantin Ulrich, Maximilian R. Rokuss, Tassilo Wald, Karol Gotkowski, Benjamin Hamm, Raphael Stock, Nico Disch, Michael Baumgartner, Dimitrios Bounias, Anand Deshpande, Stefan Dinkelacker, Stefan Dvoretskii, Katharina Eckstein, Selen Erkan, Jessica Kächele, Kim-Celine Kahl, Balint Kovacs, Lucas Kulla, Moritz Langenberg, Philipp Schader, Stephen Schaumann, Darya Trofimova, Shuhan Xiao, Sebastian Ziegler, David Zimmerer, Marco Nolden, Fabian Isensee, Klaus Maier-Hein, Ralf Floca

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The development of deep learning-based medical AI depends on high-quality annotated data. Yet, dataset creation remains constrained by the need for expert radiologist annotations, limiting curated datasets to relatively small cohorts. To overcome this limitation, recent efforts increasingly aggregate disparate public datasets into large-scale dataset collections. However, combining datasets at scale often obscures data provenance, introducing significant risks of reuse propagation, unintended leakage, bias amplification and distorted data distributions. In this work, we study these problems on a massive collection of 760k 3D radiological images across 1069 public datasets and provide practical resources to address it. Firstly, we formalize dataset collections as a distinct paradigm in medical image analysis and characterize their structural challenges, including reuse propagation, duplication, and provenance fragmentation. Secondly, we perform one of the first large-scale empirical studies of duplication on medical image collections and demonstrate extensive exact and near-duplicate reuse across public datasets via perceptual hashing and manual tracing on our 760k 3D radiological images across 1069 public datasets, with 118k near or exact duplicates. We make these hashes publicly available, thereby providing a standardized reference for identifying potential overlaps and shared provenance for researchers. Thirdly, owing to the insufficient robustness of hashing in isolation, we introduce MAP (Metadata for Aggregation and Provenance), a lightweight, portable metadata profile for documenting provenance, known overlaps, and deduplication decisions in dataset collections. Our contributions enable dataset collections to shift from coarse aggregations to reliable and provenance-aware data scaling mechanisms in medical image analysis. A webtool supporting our work is made available here:

Poster