1、Designation:D 4853 97(Reapproved 2002)Standard Guide forReducing Test Variability1This standard is issued under the fixed designation D 4853;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parent
2、heses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide serves as an aid to subcommittees writingand maintaining test methods.It helps to(1)determine if it ispossible to reduce test variability,and,i
3、f so,(2)provide asystematic approach to the reduction.1.2 This guide includes the following topics:Topic TitleSection NumberScope1Referenced Documents2Definitions3Significance and Use4Measures of Test Variability5Unnecessary Test Variability6Identifying Probable Causes of Test Variability7Determinin
4、g the Causes of Test Variability8Averaging9Calibration10Keywords111.3 The annexes include:Topic TitleAnnex NumberStatistical Test SelectionAnnex A1Frequency Distribution IdentificationAnnex A2Design of Ruggedness TestsAnnex A3Ruggedness Test Analysis:Unknown or Undefined DistributionSmallSampleAnnex
5、 A4Unknown or Undefined DistributionLargeSampleAnnex A5Binomial DistributionAnnex A6Poisson DistributionAnnex A7Normal DistributionAnnex A8Design of a Randomized Block ExperimentAnnex A9Randomized Block Experiment Analysis:Unknown or Undefined DistributionSmallSampleAnnex A10Unknown or Undefined Dis
6、tributionLargeSampleAnnex A11Binomial DistributionAnnex A12Poisson DistributionAnnex A13Normal DistributionAnnex A14Averaging:No CompositingAnnex A15CompositingAnnex A162.Referenced Documents2.1 ASTM Standards:D 123 Terminology Relating to Textiles2D 1907 Test Method for Yarn Number by the SkeinMeth
7、od2D 2256 Test Method for Tensile Properties of Yarns by theSingle-Strand Method2D 2904 Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed Data2D 2906 Practice for Statements on Precision and Bias forTextiles2D 3512 Test Method for Pilling Resistance and
8、Other Re-lated Surface Changes of Textile Fabrics:Random TumblePilling Tester Method3D 3659 Test Method for Flammability of Apparel Fabricsby Semi-Restraint Method3D 4356 Practice for Establishing Consistent Test MethodTolerances3,4D 4467 Practice for Interlaboratory Testing of a TestMethod that Pro
9、duces Non-Normally Distributed Data3D 4686 Guide for Identification of Frequency Distributions3D 4854 Guide for Estimating the Magnitude of Variabilityfrom Expected Sources in Sampling Plans3E 456 Terminology Relating to Quality and Statistics4E 1169 Guide for Conducting Ruggedness Tests42.2 ASTM Ad
10、juncts:TEX-PAC5NOTE1Tex-Pac is a group of PC programs on floppy disks,availablethrough ASTM Headquarters,100 Barr Harbor Drive,West Consho-hocken,PA 19428,USA.The analysis described in Annex A4 can beconducted using one of these programs.3.Terminology3.1 Definitions:3.1.1 average,nfor a series of ob
11、servations,the totaldivided by the number of observations.(Syn.arithmeticaverage,arithmetic mean,mean)3.1.2 block,nin experimenting,a group of units that isrelatively homogeneous within itself,but may differ from othersimilar groups.3.1.3 degrees of freedom,nfor a set,the number of valuesthat can be
12、 assigned arbitrarily and still get the same value foreach of one or more statistics calculated from the set of data.1This guide is under the jurisdiction of ASTM Committee D13 on Textiles andis the direct responsibility of Subcommittee D13.93 on Statistics.Current edition approved Sept.10,1997.Publ
13、ished August 1998.Originallypublished as D4853 88.Last previous edition D4853 91.2Annual Book of ASTM Standards,Vol 07.01.3Annual Book of ASTM Standards,Vol 07.02.4Annual Book of ASTM Standards,Vol 14.02.5PC programs on floppy disks are available through ASTM.For a 312inch diskrequest PCN:12-429040-
14、18,for a 512inch disk request PCN:12-429041-18.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.3.1.4 duplicate,nin experimenting or testing,one of twoor more runs with the same specified experimental or testconditions but with each experi
15、mental or test condition notbeing established independently of all previous runs.(Comparereplicate)3.1.5 duplicate,vtin experimenting or testing,to repeat arun so as to produce a duplicate.(Compare replicate)3.1.6 error of the first kind,a,nin a statistical test,therejection of a statistical hypothe
16、sis when it is true.(Syn.TypeI error)3.1.7 error of the second kind,b,nin a statistical test,theacceptance of a statistical hypothesis when it is false.(Syn.Type II error)3.1.8 experimental error,nvariability attributable only toa test method itself.3.1.9 factor,nin experimenting,a condition or circum-stance that is being investigated to determine if it has an effectupon the result of testing the property of interest.3.1.10 interaction,nthe condition that exists among fac-tors when a test result
