Developed by Subcommittee: D13.93
WITHDRAWN, NO REPLACEMENT
This practice covers design and analysis of interlaboratory testing of a test procedure in the case where the resulting test data are discrete variates or are continuous variates not normally distributed. This practice applies to all such interlaboratory tests used to validate a test procedure.
This practice is being withdrawn because D13 no longer has the expertise to maintain and statistical standards are being maintained by Committee E11.
Formerly under the jurisdiction of Committee D13 on Textiles and the direct responsibility of Subcommittee D13.93 on Statistics, this practice was withdrawn in February 2010 with no replacement.
1.1 This practice covers design and analysis of interlaboratory testing of a test procedure in the case where the resulting test data are discrete variates or are continuous variates not normally distributed. This practice applies to all such interlaboratory tests used to validate a test procedure.
1.2 Analysis of interlaboratory test results permits validation that the process of using the test method is in statistical control and provides the information required to write statements on precision and bias as directed in Practice D2906. It also gives the information for determining the number of specimens per unit in the laboratory sample as required in Practice D2905.
1.3 Precision statements for non-normally distributed data can be written as a function of the level of the property of interest without an interlaboratory test if the underlying distribution is known and statistical control can be assumed.
1.4 If the underlying distribution is unknown, the precision of the test method can only be approximated. There are no generally accepted methods of making approximations of this sort.
1.5 If statistical control cannot be assumed, then a meaningful precision statement cannot be written and the test method should not be used.
1.6 This practice is intended for use with data from test methods that cannot be properly modeled by a normal distribution. See Practices D2904 and E691 for applications that can be modeled by a normal distribution.
1.7 This practice includes the following sections:
|Significance and Uses||4|
|Basic Statistical Design||6|
|Pilot-Scale Interlaboratory Test||7|
|Full-Scale Interlaboratory Test||8|
|Interpretation of Data||11|
|Pilot-Scale and Full-Scale Interlaboratory Tests||Annex A1|
|Calculation of Chi-Square||Annex A2|
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D123 Terminology Relating to Textiles
D2904 Practice for Interlaboratory Testing of a Textile Test Method that Produces Normally Distributed Data
D2905 Practice for Statements on Number of Specimens for Textiles
D2906 Practice for Statements on Precision and Bias for Textiles
D4646 Test Method for 24-h Batch-Type Measurement of Contaminant Sorption by Soils and Sediments
D4853 Guide for Reducing Test Variability
E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E1169 Guide for Conducting Ruggedness Tests