Hapax · Case study · Contract review
The full run from the case study above: fifty real contracts through the learning pipeline, a hundred held out for testing. Browse the matchers the system wrote, the categories it gave up on, and the predictions that were right and wrong.
I · The two ends of contract language
The whole case turns on this distinction. A governing-law clause is written nearly the same way in thousands of contracts; a negotiated term is written once. Code can learn the first kind. Only judgment covers the second.
II · The stream
Each batch the model was asked only the questions no matcher had earned. Gold markers are matcher births; wine markers are demotions – a matcher killed in flight by a shadow check. The narrowing was won, and then partly lost, and both movements are in the data.
III · The centrepiece
A automatable P partial – code answers the formulaic instances, the model keeps the rest R model-resident. The misses run in both directions: every category we promised would fully automate died by demotion, and four categories we wrote off grew narrow, accurate matchers. Wrong predictions stay in print.
Try this – filter to the eight we got wrong, then click into one. Each row opens the real contract language it was learned from, the matcher’s actual code, and a live disagreement against the key on a named contract.
Model accuracy: measured on the 50 learning contracts. Matcher accuracy: measured on the 100 held out. The two are not directly comparable.
IV · The examination
Active matchers ran alone over the holdout, at zero marginal cost. Where a matcher chose to answer it was near-perfect on presence – but read the bars honestly: matchers answer only the instances they trust, so their accuracy is over an easier subset than the model’s. Audit Rights activated and then matched nothing at all; Expiration Date got two of its four answers wrong – a silently wrong deterministic date, exactly the failure mode our prediction table warned about.
V · Trust, then verify
VI · The adjudication
The key was never edited. As-marked scores stand; the adjudication is published beside them. Against everything marked, the arguable key errors amount to roughly 2% – the ordinary margin of expert annotation.
VII · Cost
VIII · Beyond this dataset
An overseer watches which review questions keep getting answered by the same handful of phrasings and writes ordinary code to take them over; the model keeps everything genuinely negotiated, permanently. What doesn’t transfer is the count – which categories automate, and how many, depends on your documents. We pre-registered a split and let the data mark eight of our twelve guesses wrong.
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