DoubtBench: Does Self-Doubt Help Language Models—or Just Make Them Check?

Rishi Ahuja 1 , Rajeev Ranjan Dwivedi 2 , Dr. Vinod K. Kurmi 2*

  1. 1 Department of Information Technology, National Institute of Technology Jalandhar
  2. 2 Visual Data Computing Group (VisDom), Department of Data Science and Engineering, IISER Bhopal

* Corresponding author

When a prompt asks a language model to doubt itself and check its answer, which instruction changes its performance? DoubtBench holds the task fixed and separates the two components to measure what self-doubt adds beyond checking.

Findings of WSDM 2027

The question

A prompt can combine self-doubt wording with an instruction to check its work. If its answer improves, that comparison alone cannot tell us which part of the instruction helped.

DoubtBench asks a more specific question: does adding self-doubt wording change performance once a direct checking instruction is already present? Here, self-doubt refers to the wording of the prompt. The benchmark measures observable task performance and makes no claim that a model experiences doubt or emotion.

A paired experiment

The same latent task, gold answer, model checkpoint, and decoding setup are held fixed while the prompt changes. Four conditions form the core experiment:

  • A neutral prompt.
  • Self-doubt wording alone.
  • A direct instruction to check.
  • Self-doubt wording combined with checking.

A fifth condition combines checking with a request for concision. All five are evaluated in two contexts: a minimal task request and a request that already asks for visible intermediate reasoning. This produces ten paired responses per model–task pair.

The central measure, the Conditional Doubt Effect (CDE), compares doubt plus checking with checking alone. It isolates the incremental accuracy change associated with adding the tested self-doubt wording.

Benchmark at a glance

  • 6,400 latent tasks across eight task families and 33 task types.
  • Four independently seeded splits, with exact answers and deterministic scoring.
  • Six model checkpoints drawn from four foundation-model families, including two additional Tulu checkpoints for a within-lineage post-training comparison.
  • 423,600 responses: 384,000 factorial responses and 39,600 responses in the surface-form audit.
  • 330 tasks with 660 answer-preserving variants, testing whether the effect survives changes in how a task is presented.

The task families cover working memory, inhibition, rule switching, novel-rule learning, error monitoring, planning, relational integration, and goal management.

What adding doubt changes

Across the evaluated checkpoints, overall CDE ranges from −1.43 to +2.59 percentage points. Its direction and magnitude vary across models and task families.

Context also matters. Four of six checkpoints show positive incremental CDE under minimal task requests; only two do when visible intermediate reasoning is already requested. An effect that appears helpful with sparse instructions can weaken or reverse when the task already supplies more guidance.

The paper reports baseline competence, checking gain, context modulation, seed consistency, and surface robustness separately. This keeps distinct behaviours visible rather than collapsing them into a single leaderboard score.

What this means

The tested self-doubt wording is not a portable correction policy. Its incremental value beyond checking depends on the checkpoint, task family, existing instructions, and surface form. Checking gains are also model-dependent, so the practical recommendation is to validate the instruction on the intended model and task.

These findings concern the fixed prompt wording and procedurally generated task types studied in the paper. Small effect estimates are sensitive to wording, and the Llama result is additionally sensitive to completion quality. The benchmark supports controlled attribution within this setting; it does not establish a universal effect of self-doubt prompting.

Cite

@inproceedings{ahuja2027doubtbench,
  title     = {DoubtBench: Does Self-Doubt Help Language Models---or Just Make Them Check?},
  author    = {Ahuja, Rishi and Dwivedi, Rajeev Ranjan and Kurmi, Vinod K.},
  booktitle = {Findings of WSDM 2027},
  year      = {2027},
  note      = {Accepted for publication}
}

More research