Skip to main content
SpringerLink
Log in

Comparing uncertainties—Are they really different?

  • General Paper
  • Published:
Accreditation and Quality Assurance Aims and scope Submit manuscript

Abstract

Uncertainties occur at all stages of a measurement process. Quantification of these uncertainties is important in order to make reliable decisions based on these measurement results. In some cases it can be useful to be able to compare the uncertainties associated with different measurement methods, in order to establish the method that is most reliable. A comparison can also be made between uncertainties that have themselves been evaluated using different estimation procedures. This paper discusses the comparison of uncertainties in chemical measurements using case study examples. Depending on the context, both exact and approximate F-tests are used to compare the ratios of uncertainties, while in some cases the approach is to compare separate confidence intervals.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  1. Ellison SLR, Williams A (Eds.) Eurachem/CITAC guide: Quantifying uncertainty in analytical measurement, Third edition, (2012) ISBN 978–0–948926–30–3 https://www.eurachem.org/index.php/publications/guides/quam

  2. International Organization for Standardization. ISO/IEC Guide 98–4:2012(en) Uncertainty of measurement — Part 4: Role of measurement uncertainty in conformity assessment. ISO: Geneva, Switzerland https://bbn.isolutions.iso.org/obp/ui#iso:std:iso-iec:guide:98:-4:ed-1:v1:en

  3. International Organization for Standardization. ISO/IEC Guide 98–3:2008(en) Uncertainty of measurement - Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) . ISO: Geneva, Switzerland https://bbn.isolutions.iso.org/obp/ui#iso:std:iso-iec:guide:98:-3:ed-1:v2:en5

  4. International Organization for Standardization. ISO/IEC Guide 99:2007(en) International vocabulary of metrology — Basic and general concepts and associated terms (VIM). ISO: Geneva, Switzerland https://bbn.isolutions.iso.org/obp/ui#iso:std:iso-iec:guide:99:ed-1:v2:en

  5. Ramsey MH, Ellison SLR, Rostron PD (Eds.) (2019) Eurachem/EUROLAB/ CITAC/Nordtest/AMC Guide: measurement uncertainty arising from sampling: a guide to methods and approaches. Second Edition, Eurachem. ISBN (978–0–948926–35–8) https://www.eurachem.org/index.php/publications/guides/musamp

  6. Lyn JA, Ramsey MH, Coad S, Damant AP, Wood R, Boon KA (2007) The duplicate method of uncertainty estimation: Are eight targets enough? Analyst 132:1147–1152

    Article  CAS  Google Scholar 

  7. AMC (1989) Robust statistics - how not to reject outliers. Part1, basic concepts. Analyst 114:1693–1697

    Article  Google Scholar 

  8. AMC (2020) RANOVA3 computer program https://www.rsc.org/membership-and-community/connect-with-others/through-interests/divisions/analytical/amc/software/

  9. Rostron PD, Fearn T, Ramsey MH (2020) Confidence intervals for robust estimates of measurement uncertainty. Accred Qual Assur 25:107–119

    Article  Google Scholar 

  10. Schenker N, Gentleman JF (2001) On judging the significance of differences by examining the overlap between confidence intervals. Am Stat 55(3):182–186

    Article  Google Scholar 

  11. Horwitz W (1990) Nomenclature for sampling in analytical chemistry (Recommendations 1990) International Union for Pure and Applied Chemistry. Pure Appl Chem 62:1193–1208

    Article  CAS  Google Scholar 

  12. Rostron PD, Ramsey MH (2017) Quantifying heterogeneity of small test portion masses of geological reference materials by PXRF: implications for uncertainty of reference values. Geostand Geoanal Res 41(3):459–473

    Article  CAS  Google Scholar 

  13. Webb PC, Thompson M, Potts PJ, Wilson SA (2014) GeoPT35A — An international proficiency test for analytical geochemistry laboratories — Report on supplementary round 35A (metalliferous sediment, SdAR-H1) https://www.google.com/search?client=firefox-b-d&q=GeoPT35AReport.pdf

  14. Ramsey MH, Wiedenbeck M (2017) Quantifying isotopic heterogeneity of candidate reference materials at the picogram sampling scale. Geostandards Geoanal Res 42(1):5–24

    Article  Google Scholar 

  15. Jean OJ (1961) Multiple comparisons among means. J Am Stat Assoc 56(293):52–64

    Article  Google Scholar 

  16. Ramsey MH, Geelhoed B, Wood R, Damant AP (2011) Improved evaluation of measurement uncertainty from sampling by inclusion of between-sampler bias using sampling proficiency testing. Analyst 136:1313–1321

    Article  CAS  Google Scholar 

  17. Thompson M, Fearn T (1996) What exactly is fitness for purpose in analytical measurement? Analyst 121:275–278

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9QG, UK

    Peter D. Rostron & Michael H. Ramsey

  2. Department of Statistical Science, University College London, Gower Street, London, WC1E 6BT, UK

    Tom Fearn

Authors
  1. Peter D. Rostron
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Tom Fearn
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Michael H. Ramsey
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Peter D. Rostron.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Based upon a presentation by the first author at the EURACHEM Workshop ‘Uncertainty from sampling and analysis for accredited laboratories’, November 2019, Berlin, Germany.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Rostron, P.D., Fearn, T. & Ramsey, M.H. Comparing uncertainties—Are they really different?. Accred Qual Assur 27, 133–142 (2022). https://doi.org/10.1007/s00769-022-01501-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00769-022-01501-2

Keywords

Search

Navigation