Division 9.5 Criteria for the acceptance and rejection of duplicatesF1F2
United Kingdom
The normalised error, defined below, shall be used to determine whether the two results of a duplicate analysis are homogenous or statistically acceptable:
Where Me 1 and Me 2 are the medians of the two duplicates (respectively first and second analysis) and U 1 and U 2 are the expanded uncertainties obtained for the two values, calculated as follows as specified in Appendix:
U 1 = c × s * and
For the expanded uncertainty, c = 1,96; hence:
U 1 = 0,0196 × CV r × M e1
where CV r is the robust coefficient of variation.
For it to be stated that the two values obtained are not statistically different, E n must be equal to or less than 1,0.
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- F1
- F2