1、Designation:D736608(Reapproved 2019)Standard Practice forEstimation of Measurement Uncertainty for Data fromRegression-based Methods1This standard is issued under the fixed designation D7366;the number immediately following the designation indicates the year oforiginal adoption or,in the case of rev
2、ision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice establishes a standard for computing themeasurement uncertainty for applicable test methods
3、 in Com-mittee D19 on Water.The practice does not provide a single-point estimate for the entire working range,but rather relatesthe uncertainty to concentration.The statistical technique ofregression is employed during data analysis.1.2 Applicable test methods are those whose results comefrom regre
4、ssion-based methods and whose data are intra-laboratory(not inter-laboratory data,such as result fromround-robin studies).For each analysis conducted using such amethod,it is assumed that a fixed,reproducible amount ofsample is introduced.1.3 Calculation of the measurement uncertainty involves thean
5、alysis of data collected to help characterize the analyticalmethod over an appropriate concentration range.Examplesources of data include:(1)calibration studies(which may ormay not be conducted in pure solvent),(2)recovery studies(which typically are conducted in matrix and include allsample-prepara
6、tion steps),and(3)collections of data obtainedas part of the methods ongoing Quality Control program.Useof multiple instruments,multiple operators,or both,andfield-sampling protocols may or may not be reflected in thedata.1.4 In any designed study whose data are to be used tocalculate method uncerta
7、inty,the user should think carefullyabout what the study is trying to accomplish and muchvariation should be incorporated into the study.General guid-ance on designing studies(for example,calibration,recovery)is given in Appendix X1.Detailed guidelines on sources ofvariation are outside the scope of
8、 this practice,but generalpoints to consider are included in Appendix X2,which is notintended to be exhaustive.With any study,the user must thinkcarefully about the factors involved with conducting theanalysis,and must realize that the computed measurementuncertainty will reflect the quality of the
9、input data.1.5 Associated with the measurement uncertainty is a user-chosen level of statistical confidence.1.6 At any concentration in the working range,the measure-ment uncertainty is plus-or-minus the half-width of the predic-tion interval associated with the regression line.1.7 It is assumed tha
10、t the user has access to a statisticalsoftware package for performing regression.A statisticianshould be consulted if assistance is needed in selecting such aprogram.1.8 A statistician also should be consulted if data transfor-mations are being considered.1.9 This standard does not purport to addres
11、s all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.10 This international standard was developed i
12、n accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 A
13、STM Standards:2D1129 Terminology Relating to Water3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 confidence level,nthe probability that the predictioninterval from a regression estim
14、ate will encompass the true1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.02 on Quality Systems,Specification,and Statistics.Current edition approved Dec.1,2019.Published January 2020.Originallyapproved in 2008.Last previou
15、s approval in 2013 as D7366 08(2013).DOI:10.1520/D7366-08R19.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyr
16、ight ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.value of the amount or concentration of the analyte in asubsequent measurement.Typi