miss
A real fault that raises no alert.
A miss (false negative) is a fault condition the detector fails to report; raising thresholds, or a baseline that learns the fault, increases misses.
Examples
With the raise line at z = 6, the slowly growing imbalance is learned into the baseline, and a fan shaking at 70 mg scores z = 1.6: never alerted.
A fixed backstop rule such as "RMS above 80 mg is always an alert" guards against a learned baseline causing a miss.
See also