ResearchResearch paperTraining & Scaling · Efficiency & Inference · Reinforcement Learning1 source · Oct 8, 2026

Scalable AI Uncertainty Quantification via Generalized Laplace Active Subspaces

We propose a low-rank generalized Laplace approximation for neural-network UQ based on a small number of data-informed curvature directions.

Key points

  • Reliable uncertainty quantification (UQ) is essential for deploying neural networks in scientific and high-stakes applications, but full Bayesian inference over the network parameters is computationally infeasible.
  • Starting from a generalized Bayesian posterior defined through an empirical loss, we construct a local Gaussian approximation around a pretrained set of weights in this active curvature subspace.
  • The generalized Bayesian formulation allows us to compare two posterior scalings: the standard Bayesian scaling associated with the summed negative log likelihood, and a mean-loss scaling in which the empirical loss is normalized by the number of data.
  • These results indicate that generalized Laplace active subspaces provide a practical and scalable route to calibrated uncertainty quantification in neural networks.

Sources (1)

  • [1]Scalable AI Uncertainty Quantification via Generalized Laplace Active Subspaces
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 8, 11:31 AM
    We propose a low-rank generalized Laplace approximation for neural-network UQ based on a small number of data-informed curvature directions.
    Reliable uncertainty quantification (UQ) is essential for deploying neural networks in scientific and high-stakes applications, but full Bayesian inference over the network parameters is computationally infeasible.

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