The certificate
A number you can publish next to your result
Reproducible from a published method, so a challenge can be answered with a re-run rather than an argument.
Contamination detected
internal-agent-v4
Items
180
Suspect
22
p-value
<0.001
Permutations
4,000
Items with n-gram overlap ≥ 0.6 score 95.5% against 70.2% for the rest — a gap of 25.3 points, which a permutation test on 4,000 relabellings puts at p < 0.001.
Reported score 73.3%. On clean items only, 70.2%. Overlap is a proxy: this bounds lexical memorisation, not all memorisation.