Dose 2016

The coverage factor and expanded uncertainty

A last remark on the probability range of uncertainty:

We know: The combined (standard) uncertainty is the positive square root

of the sum of variances weighted according to how the result is influenced

by varying different influence components (if not correlated).

2

  ∂

N

f

∑

2

= +

x ⋅   ∂ 

u

u ( x )

c

i

i

i =

1

If this standard uncertainty is used as the quoted range, then the

measurand lies within ξ ± σ

with a probability of 67%.

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