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non-determinism

When a system is run again under seemingly identical conditions, it may give different results. This unpredictability can come from hidden randomness, tiny changes in hardware or software settings, or even the current date. It matters because a single measurement might be a fluke, and conclusions drawn from that measurement can be wrong.

The papers show that this instability is widespread and often underestimated. Repeated runs of the same model or judge produce different scores, and changes like batch size, precision, or system prompt date can shift results more than the choice of model. This variability breaks reproducibility and makes leaderboards and automated evaluations unreliable unless stability is explicitly measured and reported.

Papers
31
Released code
3
First seen
Sept 2026
Latest
Nov 2026

29 papers in the last two months, against 2 in the two before.

Start here

Three papers to read first, in the order they came out
  1. 1Mean benchmark accuracy misleads model release decisions; recipe cards certify tail risk

    Mean accuracy is the wrong estimand for model release decisions; tail failure probability should be certified instead.

    Oct 2026
  2. 2Language models’ jailbreak weaknesses depend more on training randomness than data

    A model's vulnerability to specific jailbreaks is determined mostly by its pretraining run, not by its pretraining data or safety post-training seed.

    Oct 2026
  3. 3AI model rankings can reverse when prompts include solved examples

    Model-derived measurements should be corrected only when their repeatability is clear, and model rankings should be compared separately across prompt settings.

    Oct 2026

Who is working on it

University College London 2Microsoft 2Stanford University 2

The papers

Most central to this idea first, not most recent.

Concepts are extracted from each paper and reused across the corpus, so this page grows on its own as the desk reads.