Current date in system prompts skews LLM evaluation results

The authors show that LLM accuracy varies by up to 14% on math reasoning and reshuffles leaderboards when only the date changes, making the effect larger than other known sources of non-determinism.

Academic
Mario Sanz-Guerrero · Minh Duc Bui · Manuel Mager · Katharina von der Wense

Johannes Gutenberg University Mainz · Universidad Iberoamericana · University of Colorado Boulder

Research Digest··3 min read
Sanz-Guerrero et al.

The authors tested 9 LLMs (including Llama, Mistral, and GPT series) on 6 standard benchmarks: MMLU for MCQA, GSM8K for math reasoning, HumanEval for code generation, and FLORES-200 for machine translation, among others.

Why this paper

From Johannes Gutenberg University Mainz and 2 others

In one line

Hidden dates in system prompts cause LLM evaluation scores to fluctuate by up to 14% and reorder model rankings.

What we could check

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  • ·No weights link found
  • ·No dataset link found
  • ·No compute details found
  • ·No stated limitations found
  • ✓Reports numbers on named benchmarks (4 benchmarks)

Observed from the paper text and links we have. Absence here means we did not find it, not that it does not exist.

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Research Digest

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