Designation:D4697–95(Reapproved2001)StandardGuideforMaintainingTestMethodsintheUser’sLaboratory1ThisstandardisissuedunderthefixeddesignationD4697;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisguideisintendedtoassistlaboratoriesinmaintain-ingprecisionandcontrollingbiasintesting.Itincludesstatisticalproceduresfordetectinglackofcontrol,changesincalibrationconstants,andinoperatortechnique.Suggestionsaregivenforthecorrectionofsomeoutofcontrolsituations.1.2Thisguideincludesthefollowingtopics:TopicTitleSectionNumberScope1ReferencedDocuments2Terminology3SignificanceandUse4CalibrationControl5TestPerformanceControl6Annexes:CalibrationControlAnnexA1TestPerformanceControlAnnexA21.3Thisstandarddoesnotgiveallofthedetailsforpreparingstatisticalqualitycontrolchartsorthestatisticaltestsusedtointerpretthem,butsuchinformationmaybefoundeasilyinanumberofpublications.22.ReferencedDocuments2.1ASTMStandards:D123TerminologyRelatingtoTextiles3D1578TestMethodforBreakingStrengthofYarninSkeinForm3E456TerminologyRelatingtoQualityandStatistics42.2ASTMAdjuncts:TEX-PAC5NOTE1—Tex-PacisagroupofPCprogramsonfloppydisks,availablethroughASTMHeadquarters,100BarrHarborDrive,Conshohocken,PA19428,USA.Thecontrolchartparametersdescribedintheannexesofthisguidecanbecalculatedwithoneoftheseprogramsandthecontrolchartsscreenplotted.3.Terminology3.1Definitions:3.1.1accuracy,n—ofatestmethod,thedegreeofagree-mentbetweenthetruevalueofthepropertybeingtested(oranacceptedstandardvalue)andtheaverageofmanyobservationsmadeaccordingtothetestmethod,preferablybymanyobservers.(Seealsobiasandprecision.)3.1.2attributedata,n—observedvaluesordeterminationswhichindicatethepresenceorabsenceofspecificcharacter-istics.3.1.3bias,n—instatistics,aconstantorsystematicerrorintestresults.3.1.3.1Discussion—Biascan...
