The evaluation of measurement uncertainties and its epistemological ramifications

International audienceThe way metrologists conceive of measurement has undergone a major shift in the last two decades. Thisshift can in great part be traced to a change in the statistical methods used to deal with the expression ofmeasurement results, and, more particularly, with the calculation of measurement uncertainties. Indeed,as we show, the incapacity of the frequentist approach to the calculus of uncertainty to deal with systematicerrors has prompted the replacement of the customary frequentist methods by fully Bayesianprocedures. The epistemological ramifications of the Bayesian approach merge with a deep empiricistmood tantamount to an “epistemic turn”: measurement results are analysed in terms of degrees of belief,and central concepts such as error and accuracy are called into question. We challenge the perspectiveentailed by this epistemic turn: we insist on the centrality of the concepts of error and accuracy byunderlining the intentional character of measurement that is intimately linked to the process ofcorrection of experimental data. We further circumvent the difficulties posed by the classical analysis ofmeasurement by stressing the social rather than the epistemic dimension of measurement activities