The stated chance that the quoted interval captures the measurand's value. Calibration and testing labs standardize on about 95 %, which ties to k = 2 for normally distributed outputs, while some safety-critical and legal metrology work uses 99 % or higher. Certificates often word it as a level of confidence, though the probability strictly comes from the assigned distribution rather than a classical confidence interval.
Cert says 95 percent coverage probability but k equals 3, somebody's template is wrong.
Also heard as
- level of confidence
- confidence level
Related terms
Coverage interval
The interval around a result that contains the measurand's plausible values with a stated probability.
Coverage factor
The multiplier applied to combined standard uncertainty to obtain expanded uncertainty, usually k = 2.
Expanded uncertainty
Combined standard uncertainty multiplied by a coverage factor to give an interval with a stated coverage probability.
Normal distribution
The bell-shaped distribution assumed for most certificate values and averaged readings, set by mean and standard deviation.