Dose 2016

Combined uncertainty

In most cases a measurand, now called Y, is not measured directly, but is determined from N other input quantities X 1 , X 2 , …. , X N , through a functional relationship f :

1 2 N Y f ( X , X ,.....X ) =

The functional relationship f is also referred to as the model equation for the measurand.

The set of input quantities X 1 , X 2

, ..., X

N may be differentiated into two

following categories:

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