NeurIPS 2026 论文列表

Cross-entropy (CE) is the default training loss for supervised classification, but its sample efficiency is limited when labels are scarce. Existing remedies primarily act on the data side, via augmentation, synthesis, or transfer from pretrained models; the training objective itself is rarely revisited. We revisit it here. Drawing on the classical observation that generative classifiers reach their asymptotic error with fewer samples than discriminative ones, we propose Generative Cross-Entropy (GenCE), a drop-in replacement for CE that introduces a generative learning principle into a standard discriminative network without altering the architecture or fitting a separate density model. GenCE follows from a Bayesian rewrite of the class-conditional likelihood and, in the mini-batch approximation, reduces to normalizing each sample's softmax score against the model's predictions on the batch, coupling the training signal across examples sharing a class. We extend the proper-scoring-rule framework to such non-local losses and prove that GenCE is strictly proper under a mild completeness condition: its population risk is uniquely minimized at the true posterior. Across three datasets, on two architectures and in both balanced small-data and class-imbalanced regimes, GenCE outperforms CE and other widely used losses, while also producing better-calibrated probabilities and stronger out-of-distribution detection.

Conformal prediction provides model-agnostic uncertainty quantification with guaranteed coverage, but conventional methods often yield overly conservative uncertainty sets, particularly in multimodal or heterogeneous settings. This inefficiency arises from two sources: (i) limited expressiveness of the predictive model and (ii) simplistic nonconformity scores design. Most existing approaches advance only one of these axes, leaving the other underexplored. We propose generative conformal prediction with **O**ptimized **R**anking and **C**overage **A**llocation (ORCA), a three-stage framework that advances both aspects jointly. ORCA leverages generative models to capture the full conditional distribution and introduces a rank-dependent optimization procedure that adaptively allocates coverage for efficiency while maintaining validity. We cast this coverage allocation as an optimization problem, derive an exact mixed-integer linear programming formulation, and show that the solution converges asymptotically to the oracle density-level set. Across synthetic, semi-synthetic, and real datasets, ORCA produces substantially more efficient uncertainty sets than state-of-the-art baselines, demonstrating robust gains in scenarios where conventional conformal prediction methods fail.

Expressive generative policies such as diffusion and flow models are appealing for maximum-entropy (MaxEnt) online reinforcement learning because of their ability to model multimodal and highly non-Gaussian action distributions. However, training effective soft generative policies faces two obstacles that often arise together. First, marginal action densities are often unavailable, so existing methods typically rely on entropy bounds, heuristic proxies or approximations. Second, iterative shared-parameter samplers raise inference cost and require backpropagation through time over repeated network evaluations, increasing memory cost and destabilizing policy optimization. These obstacles motivate us to seek a generative policy that exposes a tractable MaxEnt objective while requiring only a single sampled actor forward pass for action generation. To this end, we propose soft generative actor-critic (SoftGAC), whose actor defines a stochastic bridge from a fixed base latent to a terminal action latent in pre-tanh space. This structured bridge allows us to lift the MaxEnt objective as an analytically tractable path-wise relative-entropy objective against a high-entropy reference process. In practical finite-step implementation, this relative entropy reduces exactly to sampled transition control energy and thus provides principled soft regularization. Moreover, we keep the single-pass actor lightweight by using small step-specific bridge transitions, each evaluated only once per sampled action, while maintaining a parameter budget comparable to strong actor baselines. Extensive experiments on challenging continuous-control benchmarks show that \myalgo attains higher or competitive returns than strong generative policy baselines, including diffusion and flow-matching policies, while staying in the low-latency regime of one-pass actors and avoiding the much higher cost of many-step diffusion samplers, showing considerable improvements in the compute-return tradeoff.

Unlike real-world datasets, utilizing synthetic data from generative models as train dataset necessitates a rigorous consideration of the training data's informativeness. In this paper, we propose a novel framework designed to steer diffusion models based on Bayesian epistemic uncertainty to train the target model. To ensure computational tractability, we estimate the Bayesian Active Learning by Disagreement (BALD) score by applying the Laplace approximation specifically to the last-layer parameters of the downstream model. Furthermore, we incorporate Feynman-Kac Steering (FKS) for diffusion to enhance the structural diversity of the synthetic samples and mitigate the emergence of undesirable artifacts. Extensive experiments on Imagenette and ImageNet-100 for the classification task and MS-COCO for the object detection task demonstrate that our method significantly outperforms existing baselines in downstream accuracy and OOD generalization. Furthermore, our analysis of pairwise distances between inter-class and intra-class confirms that our method effectively expands the downstream model's knowledge manifold by generating diverse and informative training signals.

Generating realistic financial time series is challenging as training data is often limited to a single historical path. With such scarce data, overfitting is hard to avoid, especially under adversarial training where a trained discriminator can memorize the training samples. To mitigate this, recent approaches train generators to minimize the discrepancy between untrained feature representations of real and generated time series. In these works, the feature maps are based on path signatures, which can fail to capture relevant time series properties at tractable truncation depths. In this work, we instead train generators by matching random convolutional features of real and generated time series. Existing random convolutional feature maps, such as Rocket and Hydra, have been shown to provide informative representations of real-world time series, but cannot supervise generative models because they are non-differentiable. We introduce **SOCK** (***SO**ft **C**ompeting **K**ernels*), a fully differentiable random convolutional feature map, suited to train generative time series models. We show that generators trained by matching random SOCK features consistently outperform signature and diffusion baselines across a wide range of small-sample financial datasets. We further demonstrate SOCK's expressiveness on two-sample hypothesis testing and time series classification tasks, where SOCK matches or outperforms existing unsupervised feature maps.

Flow matching has recently emerged as a flexible and efficient framework for generative modelling by learning deterministic transport dynamics between probability measures. In this work, we extend flow matching to the space of probability measures over probability measures, introducing a Wasserstein-on-Wasserstein (WoW) formulation. Leveraging the nested Wasserstein geometry, we show that measures over transport plans naturally induce velocity fields that realize metameasure flows. This yields a principled generalization of Wasserstein flow matching via coupled outer and inner transport plans. To address the substantial computational cost of WoW transport, we propose scalable approximations based on sliced and linear Wasserstein distances, enabling efficient training while promoting numerically stable, near-straight trajectories. Our framework unifies and extends existing approaches to point cloud and set generation, providing a practical and theoretically grounded method for generative modelling in WoW spaces.

Diffusion models are powerful generative models that produce high-quality samples from complex data. While their infinite-data behavior is well understood, their generalization with finite data remains less clear. Classical learning theory predicts that generalization occurs at a sample complexity that is exponential in the dimension, far exceeding practical needs. We address this gap by analyzing diffusion models through the lens of data covariance spectra, which often follow power-law decays, reflecting the structure of real data. To understand whether such a power-law structure can benefit learning in diffusion models, we develop a theoretical framework based on linear neural networks, congruent with a Gaussian hypothesis on the data. We quantify how the covariance spectra of data and regularization impact generalization. We find two regimes: When $N <d$, not all directions of variation are present in the training data, which results in a large gap between training and test loss. In this regime, we demonstrate how a power-law data structure, as well as regularization and early stopping help to prevent overfitting. For $N \gg d$, we find that the sampling distributions of linear diffusion models approach their optimum (measured by the Kullback-Leibler divergence) linearly with $d/N$, independent of the specifics of the data distribution. Our work clarifies how sample complexity governs generalization in a simple model of diffusion-based generative models.

We introduce a new approach to high-fidelity 3D scene reconstruction from multi-view RGB images that tightly couples reconstruction with a strong generative 3D prior. We cast scene reconstruction as conditional 3D generation over a set of spatially-localized, overlapping chunks that together tile the scene, scaling generation to large scene extents. Crucially, we inherit the fidelity and completeness of state-of-the-art generative shape models -- we use Trellis.2 as an example -- which we generalize to the scene level. To this end, we propose a projection-based conditioning mechanism that lifts posed multi-view image features into a coherent 3D representation aligned with the generative model, independent of view ordering and spatially anchored to the scene, yielding high-fidelity, multi-view consistent generated geometry. This enables lifting the strong object-level prior of Trellis.2 to multi-view, scene-scale generation, producing faithful, editable PBR mesh reconstructions of indoor environments. As a result, we obtain high-fidelity results that outperform cutting-edge reconstruction methods by 16\%.

Generative novel view synthesis from sparse input images is rarely all reconstruction or all generation: pixels visible in some source view have a unique correct value modulated only by view-dependent shading, while pixels in disocclusions or beyond the captured volume admit a distribution of plausible completions. Existing generative novel-view-synthesis methods conflate these regimes under a single uniform loss, blurring the line between geometric fidelity and creative hallucinations even when scene geometry is injected through warped point clouds or projected depth. We introduce GenRec, a multi-view flow matching model that builds the reconstruction--generation split directly into its architecture, supervision, and gradient flow. Guided by an observation mask derived from the source cameras and a monocular depth estimator, a flow matching backbone jointly denoises RGB and scene-coordinate maps across all target views, while a pixel-space refinement stage restores high-frequency detail on observed pixels; the same mask gates supervision so regression signals do not contaminate the generative prior. Across RealEstate10K, DL3DV-10K, and Mip-NeRF~360, in both single-view extrapolation and two-view interpolation, GenRec attains the best reconstruction fidelity in observed regions while also surpassing purely generative baselines on perceptual quality in unobserved ones, showing the effectiveness of our approach. The source code and trained models will be made public.

Training capable Large Language Model (LLM) agents is critically bottlenecked by the high cost and static nature of real-world interaction data. We address this by introducing GenEnv, a framework that establishes a difficulty-aligned co-evolutionary game between an agent and a scalable, generative environment simulator. Unlike traditional methods that evolve models on static datasets, GenEnv instantiates a dataevolving: the simulator acts as a dynamic curriculum policy, continuously generating tasks specifically tailored to the agent's ``zone of proximal development''. This process is guided by a simple but effective -Curriculum Reward, which aligns task difficulty with the agent's current capabilities. We evaluate \autoenv on five benchmarks, including API-Bank, ALFWorld, BFCL, Bamboogle, and TravelPlanner. Across these tasks, GenEnv improves agent performance by up to 40.3% over 7B baselines and matches or exceeds the average performance of larger models. Compared to Gemini 2.5 Pro-based offline data augmentation, \autoenv achieves better performance while using 3.3 less data. By shifting from static supervision to adaptive simulation, \autoenv provides a data-efficient pathway for scaling agent capabilities.

Egocentric gaze prediction enables many downstream applications but remains challenging, as human gaze is inherently stochastic. This stochasticity is constrained by structured temporal dynamics alternating between fixations and saccades, top-down influences from tasks, and bottom-up visual saliency. Based on this observation, we introduce GazeFlow, a framework that directly models gaze as a joint distribution of temporal gaze positions conditioned upon both top-down and bottom-up information. In particular, GazeFlow uses conditional flow matching (CFM): a learned velocity field iteratively transports a Gaussian noise sample into a plausible gaze trajectory drawn from this joint distribution. The velocity field is conditioned on bottom-up visual features extracted by a video encoder and on top-down task information obtained by globally querying these features. On standard datasets, GazeFlow achieves state-of-the-art performance on per-frame metrics, and the generated trajectories align better with human gaze temporal dynamics.

Oracle-guided biological sequence design must improve predicted function without moving outside the sequence distribution where the oracle is trustworthy. We introduce Generative Population Annealing GPA, a test-time sampler for sequence design with a frozen generator and frozen oracle. GPA instantiates annealed Sequential Monte Carlo at population scale: particles are initialized from a pretrained sequence prior, reweighted by an oracle reward tilt, selectively upsampled as effective sample size falls, mutated with the pretrained generator, and returned as the design pool. The base sampler targets a reward-tilted prior; practical variants shape the proposal or modify the objective to trade activity, specificity, fidelity, and diversity. Across enhancer and promoter benchmarks, GPA scales to thousands of sequences and is competitive with inference-time samplers, gradient-based editors, tree-search diffusion, and RL-fine-tuned generators. The same inference loop is evaluated with masked discrete-diffusion and autoregressive DNA generators. GPA reaches high predicted activity while preserving strong motif fidelity and model-based likelihood, although specialized baselines retain higher diversity or stronger $k$-mer fidelity in some settings. Cross-oracle and sequence-level audits suggest fewer obvious reward-hacking pathologies, including shorter homopolymer runs than CTRL-DNA in the HepG2 audit (5.1 bp mean maximum run versus 20.9 bp), but all validation remains computational.

Real-world multi-modal image fusion faces two fundamental challenges: spatial misalignment and complex degradations induced by heterogeneous imaging sensors. These factors are intrinsically coupled, but most existing fusion methods typically address only one of them, inevitably leading to failure under the other challenge. In this paper, we propose G2Fusion, the first fusion framework that simultaneously addresses image registration and information restoration. By developing a novel geometric-to-generative paradigm, it can directly produce high-quality fused images from unregistered and degraded inputs captured by heterogeneous imaging sensors. This framework consists of two key modules: a flow-based geometric deformation reduction module (Flow-GDR) and a DiT-based generative fusion module (DiT-GF). The former reduces large non-rigid discrepancies through dense flow estimation. The latter performs generative fusion, progressively refining residual misalignments while restoring degraded content through iterative denoising. To enable effective interaction among registration, restoration, and fusion, we design two complementary mechanisms. On the one hand, a target distribution mining strategy is introduced to construct a joint objective distribution from registration, restoration, and fusion, effectively guiding the optimization of DiT-GF. On the other hand, we develop a mutual promotion mechanism that establishes a closed-loop interaction between Flow-GDR and DiT-GF by re-estimating the residual deformation between the fused output and the infrared reference. Extensive experiments demonstrate that G2Fusion consistently outperforms state-of-the-art methods in terms of registration, restoration, and fusion.

Autoregressive large language models have dominated generative recommendation by sequentially predicting the next item. However, this unidirectional paradigm suffers from error propagation, and limited ability to jointly optimize an entire recommendation list. In this paper, we introduce Full-Sequence Masked Diffusion for generative recommendation (FSMD), which extends masked diffusion models to enable global joint modeling over the entire user history and Top-$K$ recommendation list. We formulate recommendation as a unified sequence diffusion process, where the forward process randomly masks tokens across the full sequence and the reverse process simultaneously denoises all masked positions using bidirectional context. This formulation enables parallel generation of the entire recommendation list and naturally captures inter-item dependencies within a coherent global structure. To better align generation with ranking objectives, we further introduce a unified training objective that combines masked diffusion likelihood with a listwise ranking loss. Extensive experiments on multiple public benchmarks demonstrate that FSMD consistently outperforms state-of-the-art autoregressive and item-level diffusion-based generative recommendation methods across accuracy and list quality metrics.

Engineering value is often created not by producing a single correct answer, but by improving a feasible artifact under hard constraints. We introduce **Frontier-Eng**, a benchmark for generative optimization agents that repeatedly edit executable engineering artifacts, receive frozen verifier feedback, and maximize the best feasible score found within a fixed budget. Frontier-Eng contains $47$ tasks across five engineering categories, spanning kernels, cryptography, quantum circuits, inventory and scheduling, robotics and control, optics and communication systems, structural design, reactions, and sustainable infrastructure. Each task provides a feasible starting solution, an editable artifact, and a read-only evaluator with verifier-parsed scoring, enabling cross-domain comparison without reducing engineering quality to binary pass/fail completion. We evaluate frontier models under OpenEvolve and compare search frameworks across the full task set. Current agents exhibit clear iterative improvement: **gpt-5.4** obtains the best average rank under OpenEvolve. Long-horizon runs reveal a dual **inverse-law pattern**: improvement events become rarer with iteration, and improvement magnitudes shrink with improvement count. At the same time, improvement is uneven across domains and remains sensitive to search depth, exposing a concrete frontier for engineering-oriented agents under realistic constraints and verifier-grounded feedback.

Detecting training data memorization in diffusion models is important for copyright protection and privacy auditing. We view memorization as an abnormally local concentration process: during reverse-time generation, a memorized instance acts as a point-like attractor whose probability basin is sharper and more position-sensitive than that of a generalized concept. Starting from the Fokker–Planck equation, we derive an exact evolution law for the score field $\partial_t \mathbf{s}_t$ and show that its leading geometric contribution in score-dominated local regimes is $\mathbf{H}_t \mathbf{s}_t$, linking temporal concentration dynamics to spatial curvature. We then show that standard sampling along a shared guided trajectory already exposes this curvature information through a complementary transport-curvature response, without requiring explicit Hessian computation. Motivated by this analysis, we propose the **Dynamical Singularity Metric (DSM)**, an on-trajectory detector that measures the pathwise score-evolution discrepancy between conditional and unconditional branches. DSM requires no additional backpropagation or network evaluations beyond sampling itself. Experiments on Stable Diffusion show that DSM matches or exceeds curvature-based baselines while being substantially cheaper and effective at the earliest reverse step.

Rough path signatures provide a universal feature map for continuous paths and, via the expected signature, a principled characterisation of path distributions. These results do not directly extend to \clag paths of Temporal Point Processes (TPPs), limiting the use of signature methods for event sequences. Furthermore, neural TPP models, including recent generative approaches, optimise per-event objectives with no global sequence-level loss, while evaluation of variable-length event sequences lacks distributional discrepancy measures. This paper proposes a common pathwise framework for addressing these limitations. We introduce the interarrival embedding, a stable (homeomorphic) lift from jump paths to continuous paths of bounded variation, enabling signature methods to discrete event sequences. Our theoretical contributions give rise to \sigTPP, the first signature-based generative model for TPPs, trained using a path-level loss on complete trajectories. We further analyse the space of counting paths and derive three distributional discrepancies, providing mathematically justified tools for evaluating generative TPP models. Across synthetic and real-world datasets, \sigTPP~achieves the best average rank based on 8 complementary metrics, outperforms or is within one standard error of the strongest baseline in $64\%$ of the dataset-metric pairs, and according to a relative score, improves against every baseline by at least $19\%$ on average.

Feature attributions often hide a critical modeling choice: they explain a prediction along a counterfactual path from a reference state to an input. Different baselines, interpolations, and generative trajectories define different paths and can therefor produce different explanations. We study this path ambiguity as a modeling problem. Our central question is whether the path can be chosen by the data-generating transport process, rather than by a hand-designed interpolation or by the sensitivity geometry of the model being explained. We separate attribution into fixed-path credit allocation and path selection. For a fixed path, we prove that the Aumann-Shapley line integral is the unique attribution rule under standard fixed-path axioms and explicit coordinate-trace regularity. For path selection, we minimize kinetic action over flows that transport a reference distribution to the data distribution, yielding a transport-geodesic attribution principle. We approximate this ideal with Rectified Flow and Reflow and derive stability bounds linking vector-field error to attribution error. Experiments show that lower-action, transport-consistent paths produce more stable and structured explanations, preserving competitive deletion faithfulness, without claiming data-manifold membership. Our code is available at https://anonymous.4open.science/r/temp_OTshap-6119.

Fine-tuning large-scale foundation models across resource-constrained, distributed clients presents significant computational and communication challenges. While merging Low-Rank Adaptation (LoRA) with Federated Learning (FL) enables rank-based flexibility, the interdependence of the adaptation matrices ($A$ and $B$) often complicates optimization. In this work, we theoretically demonstrate that LoRA fine-tuning with a frozen A matrix acts as a stochastic approximation of full fine-tuning, where batch gradients are subject to a random, rank-dependent perturbation. Motivated by this insight, we propose freezing and periodically resampling $A$ matrices at the client level. This strategy decouples the $A$ and $B$ gradients, diminishes LoRA low-rank constraints and reduces both computational and uplink communication overheads by 50%, allowing for the reallocation of resources toward higher adaptation ranks. Furthermore, we show that in this frozen-$A$ regime, the adaptation rank $r$ directly governs the signal-to-noise ratio (SNR) of the perturbed gradients. Specifically, we find that the SNR increases linearly with $r$, implying that clients’ learning rates must be dynamically scaled with their adaptation ranks for higher utility. Building on these foundations, we introduce Frank-LoRA, a federated rank-aware fine-tuning strategy that utilizes frozen, resampled $A$ matrices and rank-dependent learning rates for clients. We also prove the convergence of the algorithm in FL settings with heterogeneous clients resources. Our experiments across benchmark datasets demonstrate that Frank-LoRA consistently outperforms state-of-the-art baselines with half the overhead on clients.