NeurIPS 2026 Papers

We study heterogeneous treatment-effect (HTE) estimation in observational survival studies commonly associated with both censored outcomes and unmeasured confounding. We integrate causal survival forests (CSF) with negative controls (NC) from proximal causal inference and introduce Negative Control Causal Survival Forests (NC-CSF), a flexible nonparametric HTE learner for survival analysis. In particular, our approach uses a loss that incorporates proxy variables and Neyman orthogonalization to train the random forest, thereby mitigating bias from unobserved confounding and gaining robustness to nuisance estimation. Through extensive simulations spanning varying levels of confounding, proxy relevance, and censoring mechanisms, we demonstrate that NC-CSF substantially reduces bias and estimation error (root mean squared error) relative to existing baselines. We further demonstrate the practical utility of our method on real-world clinical datasets, where it confirms several existing findings and also reveals new interpretable patterns of treatment-effect heterogeneity. To facilitate practical use, we provide an end-to-end Python implementation of NC-CSF that carefully handles implementation details such as nuisance estimation and clipping.

It is often easier to destroy the causal content of a training sample than to isolate it. We use this observation to expose shortcut gradients during training. If an intervention removes the semantic evidence that justifies a sample's label while preserving nuisance structure, then any predictive gradient the model still produces on the destroyed view points toward features that can support the label without the causal signal. The destroyed view is constructed from the same sample as the clean view, and the implemented optimizer estimates this shortcut direction on the current minibatch and applies the steering step periodically. Thus CGS injects a recurring within-sample shortcut-correction signal while remaining domain-label-free and close to ERM in cost. We formalize this principle through a nuisance-only Distributionally Robust Optimization geometry, in which an adversary may perturb nuisance factors while holding the semantic component fixed. The resulting local Danskin majorizer induces a first-order robust-feasible cone in parameter space, and Causal Gradient Steering (CGS) is the closed-form projection of the ERM step onto a tractable single-normal approximation of this cone. We further prove target-risk and probe-admissibility guarantees, showing that exact counterfactual generation in pixel space is unnecessary. CGS is compatible with standard first-order training and can act either as a standalone optimizer or as a plug-in correction for existing DG algorithms. It achieves state-of-the-art performance across five standard domain generalization benchmarks. Moreover, using a single locked CGS hyperparameter configuration, it improves seventeen prior DG methods by up to +15.8 percentage points without method-specific retuning, improves OSTrack-256 across GOT-10k, UAV123, and OTB2015, and establishes new matched-protocol state of the art for domain-generalized semantic segmentation by improving SCSD from 51.42 to 52.35 mIoU on GTAV+SYNTHIA$\rightarrow$\{Cityscapes, BDD, Mapillary\} and from 35.66 to 36.99 mIoU on GTAV$\rightarrow$ACDC. Beyond this algorithm, causal signal destruction defines a research direction parallel to data augmentation. The destruction operator is a design axis, and task-specific destroyers can turn shortcut suppression into a reusable tool for broader vision problems.

Latent confounding poses a significant obstacle to identifying the causal effect of a treatment on an outcome. To address this, many existing studies leverage proxies of the latent confounder to indirectly adjust for the confounding bias. However, they impose specific structural constraints on the proxies and typically require multiple proxies. In this paper, focusing on the latent variable linear non-Gaussian acyclic model (lvLiNGAM), we propose a causal effect identification procedure requiring only a single agnostic proxy. Crucially, the term "agnostic" means that the causal connections between the proxy and the treatment-outcome pair can be arbitrary and are not required to be known a priori. This structural complexity precludes identifying the causal effect via a simple closed-form formula. Consequently, our identification procedure is designed to first derive candidate solutions from cumulants and then isolate the valid solution by examining certain independence relationships. We present a series of new theoretical results, which collectively establish the soundness of our identification procedure: given the observational population distribution, it correctly identifies the true causal effect when identifiable, and correctly reports unidentifiability otherwise. Finally, we empirically validate our theoretical results.

We introduce a categorical framework for causal abstraction that unifies and extends existing approaches. Modeling causal systems as Markov functors from free Markov categories generated by directed acyclic graphs, we define a causal abstraction as a deterministic natural transformation together with an embedding of restricted free Markov categories. This separates graphical compatibility under interventions from domain-level clustering of variables or values. Our framework provides an explicit characterization of admissible high-level graphs and recovers prior notions such as constructive -abstractions and cluster-DAG abstractions with unobserved confounders. We give concise categorical proofs that interventional distributions factorize over graphical abstractions and that do-calculus applied to the high-level graph yields valid conclusions for the low-level model.

Many decision-facing stochastic systems are observed through aggregate distributions rather than scalar trajectories: queue occupancies, mobility shares, public-health mixtures, generation-source shares, ecological compositions, and air-quality severity profiles all live on the probability simplex and evolve over time. We study causal (time-respecting online) forecasting for these distribution-valued time series and argue that the transition operator itself should be structured around the simplex. We introduce CAST (Causal Anchored Simplex Transport), a successor-local operator that (i) retrieves empirical successors from causal context, (ii) stabilizes them with a persistence anchor, and (iii) applies a bounded local stochastic transport on ordered supports; every stage preserves the simplex by construction. We identify a structural failure mode, latent transition-kernel aliasing, where similar observed distributions evolve differently under different contextual regimes, and prove that any forecaster depending only on an aliased summary incurs an irreducible weighted Jensen--Shannon excess-risk lower bound, while the CAST hypothesis class contains the regime-aware Bayes successor; for ordered supports an additional Pinsker separation holds whenever the transported successor lies outside the no-transport anchor hull. On a suite of eleven public and simulated benchmarks spanning ecology, energy, diet, mortality, employment, air quality, severe weather, mobility, and $G/G/1$, $G_t/G/1$ queue occupancy, CAST achieves the best average rank on both one-step KL (1.27) and autoregressive rollout JSD (1.91), winning 8/11 sections on each metric against a broad statistical, compositional, recurrent, convolutional, Transformer, and modern time-series baseline set, and top-2 on all 11 sections for offline KL. Component ablations and a controlled synthetic aliasing experiment corroborate the theory.

Linear structural causal models (SCMs) are used to analyze relationships among random variables. In these models, directed edges encode direct causal effects, while bidirected edges capture latent confounding. The problem of generically identifying the hidden parameters from observed correlations remains open in causal inference. The half-trek criterion by Foygel, Draisma, and Drton [2012] and its generalization to the edge-wise criterion are important criteria for generic identification in linear SCMs, since the half-trek criterion can be efficiently decided by an algorithm with running time $\mathcal{O}(n^5)$. We here develop a new criterion that is equivalent to the edgewise criterion. Utilizing this criterion, we design a faster randomized algorithm for deciding the half-trek criterion with running time $\mathcal{O}(n^4)$. For sparse graphs, our algorithm even works in $\mathcal{O}(n^3)$. We show that the algorithm is useful in practice by providing an implementation that outperforms the implementation of HTC in the state-of-the art R package SEMID.

Causal reasoning from observational data becomes significantly challenging when the underlying causal structure is only partially known. In this work, we study the the equivalence class of structural causal models (SCMs) with latent variables sharing the same set of conditional independencies, as represented by a partial ancestral graph (PAG). Specifically, we provide a new characterization of SCM-induced causal diagrams in this equivalence class using differentiable parameters. Building on this characterization, we introduce a new model class called PAG-constrained neural causal models ($\mathcal{P}$-NCMs) which parameterize this equivalence class of SCMs. We prove that $\mathcal{P}$-NCMs are expressive enough to represent counterfactual distributions induced by any SCM in the class, while remaining consistent with the structural constraints shared across all its members. Finally, we demonstrate how the differentiable parameterization of this model class enables causal inference under Markov equivalence by reducing counterfactual partial identification to an optimization problem over $\mathcal{P}$-NCMs. We establish the theoretical soundness of this approach and validate its performance on simulations.