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Combining Results from Multiple Evaluations of the Same Measurand



Raghu N. Kacker, Klaus-Dieter Sommer


According to the Guide to the Expression of Uncertainty in Measurement (GUM), a result of measurement consists of a measured value together with its associated standard uncertainty. The measured value and the standard uncertainty are interpreted as the expected value and the standard deviation of a state-of-knowledge probability distribution attributed to the measurand. We discuss the term metrological compatibility introduced by the International Vocabulary of Metrology, third edition (VIM3) for lack of significant differences between two or more results of measurement for the same measurand. Sometimes a combined result of measurement from multiple evaluations of the same measurand is needed. We propose an approach for determining a combined result which is metrologically compatible with the contributing results.
Journal of Research (NIST JRES) -


consensus value, interlaboratory evaluations, uncertainty in measurement


Kacker, R. and , K. (2011), Combining Results from Multiple Evaluations of the Same Measurand, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 14, 2024)


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Created December 1, 2011, Updated February 19, 2017