Entry 43 of 44
False Positive
falsus (spurious) + ponere (to place) — a detection placed as present, then denied
Latin
From Latin falsus: deceptive, counterfeit. Positive from ponere: to place, to put. In Neyman–Pearson statistics and later radar: a Type I error — a detection of something the criterion later declares was not there. Root concept: the detector spoke, the judge disagreed.
Established meaning
A false positive is always false relative to a threshold someone set. Lower the threshold, more positives. Raise it, more misses. The term does not describe an object in the world. It describes a disagreement between an alarm and an authority.
AI industry deployment
'50%+ drop in false positive rates' is reported as quality. The company that owns the detector also owns the label 'false.' What the scanner flagged and the process then rejected is not independently witnessed. The knock is recorded as a mistake.
Semantic gap
Who decides it wasn't there
Falsus is assigned by the one holding the criterion. Industry usage treats a dropped alert as proof the thing was absent, rather than proof the process declined to see it. The person, opening, or pattern that triggered the alarm has no standing to contest the word 'false.'