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Error and Uncertainty in Radiocarbon Measurements

Published online by Cambridge University Press:  18 July 2016

E Marian Scott*
Affiliation:
Department of Statistics, University of Glasgow, Glasgow G12 8QW, United Kingdom
Gordon T Cook
Affiliation:
SUERC, Scottish Enterprise Technology Park, East Kilbride, United Kingdom
Philip Naysmith
Affiliation:
SUERC, Scottish Enterprise Technology Park, East Kilbride, United Kingdom
*
Corresponding author. Email: [email protected]
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Abstract

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All measurement is subject to error, which creates uncertainty. Every time that an analytical radiocarbon measurement is repeated under identical conditions on an identical sample (even if this were possible), a different result is obtained. However, laboratories typically make only 1 measurement on a sample, but they are still able to provide an estimate of the analytical uncertainty that reflects the range of values (or the spread) in results that would have been obtained were the measurement to be repeated many times under identical conditions. For a single measured 14C age, the commonly quoted error is based on counting statistics and is used to determine the uncertainty associated with the 14C age. The quoted error will include components due to other laboratory corrections and is assumed to represent the spread we would see were we able to repeat the measurement many times.

Accuracy and precision in 14C dating are much desired properties. Accuracy of the measurement refers to the deviation (difference) of the measured value from the true value (or sometimes expected or consensus value), while precision refers to the variation (expected or observed) in a series of replicate measurements. Quality assurance and experimental assessment of these properties occupy much laboratory time through measurement of standards (primary and secondary), reference materials, and participation in interlaboratory trials. This paper introduces some of the most important terms commonly used in 14C dating and explains, through some simple examples, their interpretation.

Type
Articles
Copyright
Copyright © 2007 by the Arizona Board of Regents on behalf of the University of Arizona 

References

Ascough, P, Cook, G, Dugmore, A. 2005. Methodological approaches to determining the marine radiocarbon reservoir effect. Progress in Physical Geography 29(4):532–47.Google Scholar
Ascough, PL, Cook, GT, Dugmore, AJ, Scott, EM. 2007. The North Atlantic marine reservoir effect in the Early Holocene: implications for defining and understanding MRE values. Nuclear Instruments and Methods in Physics Research B 259(1):438–47.CrossRefGoogle Scholar
Bevington, PR, Robinson, DK. 2003. Data Reduction and Error Analysis for the Physical Sciences. 3rd edition. New York: McGraw-Hill. 352 p.Google Scholar
Bryant, C, Carmi, I, Cook, G, Gulliksen, S, Harkness, D, Heinemeier, J, McGee, E, Naysmith, P, Possnert, G, Scott, M, van der Plicht, J, van Strydonck, M. 2002. Sample requirements and design of a inter-laboratory trial for radiocarbon laboratories. Nuclear Instruments and Methods in Physics Research B 172(1–4):355–9.Google Scholar
Burr, GS, Donahue, DJ, Tang, Y, Beck, W, McHargue, L, Biddulph, D, Cruz, R, Jull, AJT. 2007. Error analysis at the NSF-Arizona AMS facility. Nuclear Instruments and Methods in Physics Research B 259(1):149–53.Google Scholar
Cook, GT, van der Plicht, J. 2007. Radiocarbon dating. In: Elias, SA, editor. Encyclopedia of Quaternary Science. Amsterdam: Elsevier. p 2899–911.Google Scholar
Donahue, DJ, Linick, TW, Jull, AJT. 1990. Isotope-ratio and background corrections for accelerator mass spectrometry radiocarbon measurements. Radiocarbon 32(2):135–42.Google Scholar
Gulliksen, S, Scott, EM. 1995. Report of the TIRI workshop, Saturday 13 August 1994. Radiocarbon 37(2): 820–1.Google Scholar
Kelvin, WT. 1893. Popular Lectures and Addresses, Volume 1: Electrical Units of Measurement. Lecture given to the Institute of Civil Engineers. London: McMillan & Company. p 80143.Google Scholar
Le Clercq, M, van der Plicht, J, Gröning, M. 1998. New 14C reference materials with activities of 15 and 50 pMC. Radiocarbon 40(1):295–7.Google Scholar
Mook, W, van der Plicht, J. 1999. Reporting 14C activities and concentrations. Radiocarbon 41(3):227–39.CrossRefGoogle Scholar
Royal Society of Chemistry [RSC]. 2003a. Terminology—the key to understanding analytical science. Part 1: accuracy, precision and uncertainty. AMC technical brief 13. Available online http://www.rsc.org/images/brief13_tcm18-25955.pdf.Google Scholar
Royal Society of Chemistry [RSC]. 2003b. Is my uncertainty estimate realistic? AMC technical brief 15. Available online at http://www.rsc.org/images/brief15_tcm18-25958.pdf.Google Scholar
Rozanski, K, Stichler, W, Gonfiantini, R, Scott, EM, Beukens, RP, Kromer, B, van der Plicht, J. 1992. The IAEA 14C intercomparison exercise 1990. Radiocarbon 34(3):506–19.Google Scholar
Scott, EM. 2003. The Third and Fourth International Radiocarbon Intercomparisons. Radiocarbon 45(2):135328.Google Scholar
Stuiver, M, Polach, H. 1977. Discussion: reporting of 14C data. Radiocarbon 19(3):355–63.Google Scholar
Taylor, BN, Kuyatt, CE. 1994. Guidelines for evaluating and expressing the uncertainty of NIST measurement results. Technical note 1297. Available online at http://physics.nist.gov/Pubs/guidelines/contents.html.CrossRefGoogle Scholar
Ward, GK, Wilson, SR. 1978. Procedures for comparing and combining radiocarbon age determinations: a critique. Archaeometry 20(1):1931.Google Scholar