ALBERT

Description:    An approach to estimating measurement error variances for any instrument having round-off effects that might also have instrument bias is presented. Recently finite instrument resolution effects on error variances have been studied, but negligible instrument bias was assumed and the contexts were different than considered here. Our intent is to use repeated measurements on several standards to estimate the instrument’s random and systematic error variances. Recognizing that rounding impacts item bias and variance in a manner that depends on the true value, an approach is presented to estimate random error variance and instrument systematic error variance. The key finding is that item-specific bias can interfere with the estimation of overall instrument bias unless appropriate error modeling and associated inference steps are taken. Content Type Journal Article Pages 1-13 DOI 10.1007/s00769-011-0791-0 Authors T. Burr, Statistical Sciences, Los Alamos National Laboratory, P. O. Box 1663, MS F600, Los Alamos, NM 87545, USA M. S. Hamada, Statistical Sciences, Los Alamos National Laboratory, P. O. Box 1663, MS F600, Los Alamos, NM 87545, USA T. Cremers, Nuclear Process Infrastructure, Los Alamos National Laboratory, P.O. Box 1663, MS G735, Los Alamos, NM 87545, USA B. P. Weaver, Statistical Sciences, Los Alamos National Laboratory, P. O. Box 1663, MS F600, Los Alamos, NM 87545, USA J. Howell, Department of Mechanical Engineering, University of Glasgow, University Avenue, Glasgow, G12 8QQ Scotland, UK S. Croft, Nuclear Safeguards Science and Technology, Los Alamos National Laboratory, P.O. Box 1663, MS E540, Los Alamos, NM 87545, USA S. B. Vardeman, Departments of Statistics and Industrial and Manufacturing Systems Engineering, Iowa State University, Ames, IA 50011, USA Journal Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement Online ISSN 1432-0517 Print ISSN 0949-1775