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Dataplot Vol 2 Vol 1

K CONSISTENCY STATISTIC

Name:
    K CONSISTENCY STATISTIC (LET)
Type:
    Let Subcommand
Purpose:
    Compute the k-consistency statistic of a variable as defined by the ASTM E691 standard.
Description:
    The k-consistency statistic is defined in the ASTM E691 standard as

      \( k = \frac{s} {s_r} \)

    with

      s = cell standard deviation sr = repeatability standard deviation

    Essentially, k is the ratio of the cell standard devition to the pooled value.

Syntax 1:
    LET <k> = K CONSISTENCY STATISTIC <y> <labid>
                <SUBSET/EXCEPT/FOR qualification>
    where <y> is a response variable;
                <labid> is a lab-id variable;
                <k> is a variable where the k-consistency statistic values are saved; and where the <SUBSET/EXCEPT/FOR qualification> is optional.

    This syntax is used to compute the k-consistency statistic for a single material. The number of k-values is equal to the number of laboratories.

Syntax 2:
    LET <k> <labtag> <mattag>= K CONSISTENCY STATISTIC <y> <labid> <matid>
                            <SUBSET/EXCEPT/FOR qualification>
    where <y> is a response variable;
                <labid> is a lab-id variable;
                <matid> is a material-id variable;
                <h> is a variable where the k-consistency statistic values are saved;
    <labtag> is a variable where the corresponding lab-id values are saved;
    <mattag> is a variable where the corresponding material-id values are saved;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.

    This syntax is used to compute the k-consistency statistic for multiple materials. The number of k-values is equal to the number of materials times the number of laboratories.

Examples:
    LET A = K CONSISTENCY STATISTIC Y LAB
    LET HVAL = K CONSISTENCY STATISTIC Y LAB MAT
    LET HVAL = K CONSISTENCY STATISTIC Y LAB MAT SUBSET MAT > 2
Default:
    None
Synonyms:
    None
Related Commands: Reference:
    "Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method", ASTM International, 100 Barr Harbor Drive, PO BOX C700, West Conshohoceken, PA 19428-2959, USA.
Applications:
    Interlaboratory Analysis
Implementation Date:
    2005/4
Program:
     
    SKIP 25
    READ GLUCOSE.DAT Y MATID LABID
    .
    LET KVAL LABTAG MATTAG = K CONSISTENCY STATISTIC Y MATID LABID
    .
    SET WRITE DECIMALS 4
    PRINT KVAL LABTAG MATTAG
        
    The following output is generated
     
    ---------------------------------------------
               KVAL         LABTAG         MATTAG
    ---------------------------------------------
             0.2097         1.0000         1.0000
             0.4562         2.0000         1.0000
             0.9977         3.0000         1.0000
             1.7040         4.0000         1.0000
             0.3448         5.0000         1.0000
             1.3244         6.0000         1.0000
             1.1736         7.0000         1.0000
             0.7735         8.0000         1.0000
             0.1058         1.0000         2.0000
             0.8876         2.0000         2.0000
             0.5555         3.0000         2.0000
             1.8466         4.0000         2.0000
             0.5187         5.0000         2.0000
             1.0948         6.0000         2.0000
             1.3784         7.0000         2.0000
             0.3388         8.0000         2.0000
             0.2150         1.0000         3.0000
             0.7889         2.0000         3.0000
             0.6290         3.0000         3.0000
             2.4088         4.0000         3.0000
             0.4362         5.0000         3.0000
             0.4683         6.0000         3.0000
             0.7730         7.0000         3.0000
             0.3556         8.0000         3.0000
             0.0229         1.0000         4.0000
             1.7837         2.0000         4.0000
             0.6069         3.0000         4.0000
             0.7377         4.0000         4.0000
             0.7172         5.0000         4.0000
             0.6284         6.0000         4.0000
             1.4543         7.0000         4.0000
             0.9386         8.0000         4.0000
             0.1847         1.0000         5.0000
             2.3347         2.0000         5.0000
             0.6887         3.0000         5.0000
             0.2245         4.0000         5.0000
             0.2425         5.0000         5.0000
             1.0252         6.0000         5.0000
             0.8397         7.0000         5.0000
             0.4188         8.0000         5.0000
        

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Date created: 04/19/2005
Last updated: 06/30/2015

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