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Research paperInterpretability · Large Language Models · Reasoning & Planning2 sources · Oct 6, 2026

U-Space: Uncovering When and Why Uncertainty Arises in Language Models

Large language models are informing decisions with ever-higher stakes.

Key points

  • Yet recognizing when to defer remains difficult because language models can present incorrect conclusions with fluent explanations and an authoritative tone.
  • Uncertainty quantification seeks to address this disconnect by estimating the reliability of individual predictions.
  • Building on this capability, we introduce the U-Space, a low-dimensional subspace that makes a model's evolving uncertainty measurable and interpretable.
  • We identify semantic anchors for doubt and certainty, map their unembedding directions back into the residual space, and combine their contrasts into an orthogonal basis.

Sources (2)

Extractive summary: sentences quoted from the sources.