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Evolution of Modern Approaches to Express Uncertainty in Measurement



Raghu N. Kacker, K D. Sommer, Bernd Siebert


The object of this paper is to discuss evolution of the concept of uncertainty in measurement and methods for its quantification from the classical error analysis to the modern approaches based on the Guide to the Expression of Uncertainty in Measurement (GUM). After reviewing error analysis, we discuss its limitations which motivated the experts from the International Committee for Weights and Measures (CIPM), the International Bureau of Weights and Measures (BIPM), and various national metrology institutes to develop specific recommendations which form the basis of the GUM. We discuss the new concept introduced by the GUM. Then we discuss the merits and limitations of the GUM. The limitations of GUM led the BIPM Joint Committee on Guides in Metrology (JCGM) to develop a draft Supplement 1 to the GUM (draft GUM-S1). We discuss the merits and limitations of the draft GUM-S1. Then we indicate the merits of using Bayesian methods for statistical (Type A) evaluations in the context of the GUM and its draft supplement GUM-S1.


Bayesian statistics, error analysis, uncertainty in measurement


Kacker, R. , Sommer, K. and Siebert, B. (2007), Evolution of Modern Approaches to Express Uncertainty in Measurement, Metrologia, [online], (Accessed February 26, 2024)
Created November 26, 2007, Updated October 12, 2021