Combined uncertainty factor for sampling and analysis

Ramsey, Michael and Ellison, Stephen L R (2017) Combined uncertainty factor for sampling and analysis. Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement., 22 (4). pp. 187-189. ISSN 0949-1775

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Measurement uncertainty that arises from primary sampling can be expressed as an uncertainty factor, which recognises its sometimes approximately log-normal probability distribution. By contrast, uncertainty arising from chemical analysis is usually expressed as relative uncertainty, based upon the assumptions of its approximately normal distribution. A new method is proposed that enables uncertainty from these two sources, expressed in these different ways, to be combined to produce an estimate of the total combined uncertainty of the measurement values that result when the measurement process is considered as a whole.

Item Type: Article
Keywords: Measurement uncertainty Uncertainty factor Sampling uncertainty Propagation of uncertainty
Schools and Departments: School of Life Sciences > Evolution, Behaviour and Environment
Depositing User: Michael Ramsey
Date Deposited: 30 May 2017 08:07
Last Modified: 04 Oct 2017 10:42

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