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2. Measurement Process Characterization
2.5. Uncertainty analysis
2.5.5. Propagation of error considerations

2.5.5.1.

Formulas for functions of one variable

Case: Y=f(X,Z) Standard deviations of reported values that are functions of a single variable are reproduced from a paper by H. Ku (Ku).

The reported value, Y, is a function of the average of N measurements on a single variable.

Notes
Function of

is an average of N measurements

Standard deviation of

= standard deviation of X.

 
 
 
 
 
Approximation could be seriously in error if n is small--
Not directly derived from the formulas

Note: we need to assume that the original data follow an approximately normal distribution.

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