Data leakage
Information from evaluation cases entering training, prompting, retrieval, or tuning.
What Data leakage means
It creates performance that may disappear on genuinely unseen inputs.
Terms this definition uses
Related terms in Measurement and evaluation
How a measurement earns trust: evaluation sets, error rates, calibration, reproducibility, and the biases that make a number look better than it is.
AI answer reading · name confusion · hedged answer · Benchmark · Evaluation set · Golden dataset · Ground truth · Human evaluation · LLM-as-judge · Pairwise evaluation · Pointwise evaluation · Rubric · Inter-rater agreement · Accuracy · F1 score · False positive rate · False negative · True positive · True negative · Calibration · Confidence score · Coverage · Abstention · Reproducibility · Repeatability · Variance · Confidence interval · Sample size · Sampling bias · Selection bias · Survivorship bias · Test contamination
Questions about Data leakage
What is Data leakage?
Information from evaluation cases entering training, prompting, retrieval, or tuning.
Which area of the glossary does Data leakage belong to?
Measurement and evaluation: How a measurement earns trust: evaluation sets, error rates, calibration, reproducibility, and the biases that make a number look better than it is.
← Survivorship bias · Test contamination →
See it in the full glossary · 772 terms across 19 areas.
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