Dictionary
Coverage factor
The number k by which a combined standard uncertainty is multiplied to obtain an expanded uncertainty; k = 2 is standard certificate practice, with a…
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64 results for “Coverage factor”
Our certificates all say k=2, approximately 95 % coverage. When is that wrong? When must I use the t-distribution and effective degrees of…
Dictionary
Expanded measurement uncertainty
The product of a combined standard uncertainty and a coverage factor greater than one: U = k·u꜀. With k = 2 the coverage probability is…
Documents
SOP 29 — Assignment of Uncertainty
…When there are a small number of degrees of freedom, the coverage factor must be determined by calculating the coverage factor or be taken…
Tools
Uncertainty Budget (GUM)
Combine Type A and Type B uncertainty components with distribution divisors, root-sum-of-squares and a coverage factor to an expanded uncertainty per…
Documents
SOP 27 — Rr Test Cars
…Uncertainty Component Description Symbol Source Typical Distribution Uncertainty of the master scale calibration uMS USDA calibration certificate Normal divided by the coverage factor Uncertainty…
Dictionary
Welch–Satterthwaite formula
…the degrees of freedom of its components — used to select a coverage factor from the t-distribution. GUM (JCGM 100:2008) G.4 Uncertainty
…The coverage factor, , in equation 18 is selected to assure a 95 % confidence interval level for the measurement process, consistent with NIST policy [Taylor…
…routine calibration with a directness working labs appreciate — model, budget table, coverage factor, done — and then does something rarer: a supplement of fully worked…
Documents
SOP 7 — Single Substitution
…buoyancy corrections, multiplied by a coverage factor of 2 (k = 2) for an approximate 95 percent confidence interval. Factors not considered in the evaluation…