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A Generalized Confidence Interval for a Measurand in the Presence of type-A and type-B Uncertainties



Chih-Ming Wang, Hariharan K. Iyer


We consider the problem of estimating a measurand based on a sequence of measurements. Each measurement has both type-A and type-B errors. The measurements may have been obtained from a single experiment or several separate experiments. We investigate the estimation problem under two measurement models having different sets of assumptions on type-B errors. We review commonly used procedures for obtaining a confidence interval for the measurand and discuss an alternative approach based on the principle of generalized inference. We use several examples to illustrate the proposed approach.


generalized pivotal quantity, ISO GUM, key comparisons
Created April 11, 2006, Updated January 27, 2020