ASTM_E_141_-_10.pdf

Designation:E14110An American National StandardStandard Practice forAcceptance of Evidence Based on the Results of ProbabilitySampling1This standard is issued under the fixed designation E141;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice presents rules for accepting or rejectingevidence based on a sample.Statistical evidence for thispractice is in the form of an estimate of a proportion,anaverage,a total,or other numerical characteristic of a finitepopulation or lot.It is an estimate of the result which wouldhave been obtained by investigating the entire lot or populationunder the same rules and with the same care as was used for thesample.1.2 One purpose of this practice is to describe straightfor-ward sample selection and data calculation procedures so thatcourts,commissions,etc.will be able to verify whether suchprocedures have been applied.The methods may not give leastuncertainty at least cost,they should however furnish areasonable estimate with calculable uncertainty.1.3 This practice is primarily intended for one-of-a-kindstudies.Repetitive surveys allow estimates of sampling uncer-tainties to be pooled;the emphasis of this practice is onestimation of sampling uncertainty from the sample itself.Theparameter of interest for this practice is effectively a constant.Thus,the principal inference is a simple point estimate to beused as if it were the unknown constant,rather than,forexample,a forecast or prediction interval or distributiondevised to match a random quantity of interest.1.4 A system of units is not specified in this standard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E105 Practice for Probability Sampling of MaterialsE122 Practice for Calculating Sample Size to Estimate,WithSpecified Precision,the Average for a Characteristic of aLot or ProcessE456 Terminology Relating to Quality and StatisticsE1402 Guide for Sampling DesignE2586 Practice for Calculating and Using Basic Statistics3.Terminology3.1 DefinitionsRefer to Terminology E456 for definitionsof other statistical terms used in this practice.3.1.1 audit subsample,na small subsample of a sampleselected for review of all sample selection and data collectionprocedures.3.1.2 equal complete coverage result,nthe numericalcharacteristic of interest calculated from observations made bydrawing randomly from the frame,all of the sampling unitscovered by the frame.3.1.2.1 DiscussionLocating the units and evaluating themare supposed to be done in exactly the same way and at thesame time as was done for the sample.The quantity itself isdenoted u.The equal complete coverage result is never actuallycalculated.Its purpose is to serve as the objectively definedconcrete goal of the investigation.The quantity u may be thepopulation mean,(Y),total(Y),median(M),the proportion(P),or any other such quantity.3.1.3 frame,na list,compiled for sampling purposes,which designates all of the sampling units(items or groups)ofa population or universe to be considered in a specific study.E14021This practice is under the jurisdiction ofASTM Committee E11 on Quality andStatistics and is the direct responsibility of Subcommittee E11.10 on Sampling/Statistics.Current edition approved May 15,2010.Published August 2010.Originallyapproved in 1959.Last previous edition approved in 2003 as E141 91(2003)1.DOI:10.1520/E0141-10.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.4 probability sample,na sample in which the sam-pling units are selected by a chance process such that aspecified probability of selection can be attached to eachpossible sample that can be selected.E14023.1.5 replicate subsamples,na number of disjointsamples,each one separately drawn from the frame in accordwith the same probability sampling plan.3.1.6 sample,na group of observations or test results,taken from a larger collection of observations or test results,which serves to provide information that may be used as a basisfor making a decision concerning the larger collection.E25863.1.7 sampling unit,nan item,group of items,or segmentof material that can be selected as part of a probabilitysampling plan.E14024.Significance and Use4.1 This practice is designed to permit use