SED navigation bar go to SED home page go to Dataplot home page go to NIST home page SED Home Page SED Contacts SED Projects SED Products and Publications Search SED Pages
Dataplot Vol 2 Auxiliary Chapter

DIFFERENCE OF COEFFICENT OF VARIATION

Name:
    DIFFERENCE OF COEFFICENT OF VARIATION (LET)
Type:
    Let Subcommand
Purpose:
    Compute the difference between the coefficient of variation for two response variables.
Description:
    The coefficient of variation is the standard deviation divided by the mean.

    For the differeence of the coefficient of variation, the coefficient of variation is computed for each of two samples then their difference is taken.

Syntax:
    LET <par> = DIFFERENCE OF COEFFICENT OF VARIATION <y1> <y2>
                            <SUBSET/EXCEPT/FOR qualification>
    where <y1> is the first response variable;
                <y2> is the first response variable;
                <par> is a parameter where the computed difference of the coefficient of variation is stored;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2
    LET A = DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2 SUBSET X > 1
Note:
    The difference of coefficient of variations statistic is also supported for the following commands:

      DIFFERENCE OF COEFFICENT OF VARIATION PLOT Y1 Y2 X
      CROSS TABULATE DIFFERENCE OF COEFFICENT OF VARIATION PLOT Y1 Y2 X
      BOOTSTRAP DIFFERENCE OF COEFFICENT OF VARIATION PLOT Y1 Y2
      TABULATE DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2 X
      CROSS TABULATE DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2 X
      LET Z = CROSS TABULATE DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2 X1 X2

    Enter

      HELP STATISTIC PLOT
      HELP CROSS TABULATE PLOT
      HELP BOOTSTRAP PLOT
      HELP TABULATE
      HELP CROSS TABULATE
      HELP CROSS TABULATE (LET)

    for more information on these plots and commands.

Default:
    None
Synonyms:
    None
Related Commands:
    COEFFICENT OF VARIATION = Compute the coefficient of variation.
    RELATIVE SD = Compute the relative sd.
    MEAN = Compute the mean.
    SD = Compute the sd.
    DIFFERENCE OF MEAN = Compute the difference of the means.
    DIFFERENCE OF SD = Compute the difference of standard deviations.
    DIFFERENCE OF RELATIVE SD = Compute the difference of the relative sd.
    STATISTICS PLOT = Generate a statistic versus subset plot.
    CROSS TABULATE PLOT = Generate a statistic versus two subsets plot.
    BOOTSTRAP PLOT = Generate a bootstrap plot.
    TABULATE = Perform a tabulation for a specified statistic.
    CROSS TABULATE = Perform a cross tabulation for a specified statistic.
Applications:
    Data Analysis
Implementation Date:
    3/2003
Program:
    SKIP 25 
    READ IRIS.DAT Y1 TO Y4 X 
    . 
    LET A = DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2 
    TABULATE DIFFERENCE OF COEFFICENT OF VARIATION Y1 Y2 X 
    . 
    XTIC OFFSET 0.2 0.2 
    X1LABEL GROUP ID 
    Y1LABEL DIFFERENCE OF COEFFICENT OF VARIATION 
    CHAR X 
    LINE BLANK 
    DIFFERENCE OF COEFFICENT OF VARIATION PLOT Y1 Y2 X 
    CHAR X ALL 
    LINE BLANK ALL 
    BOOTSTRAP DIFFERENCE OF COEFFICENT OF VARIATION PLOT Y1 Y2 X  
        
    Dataplot generated the following output.
           ************************************************************
           **  LET A = DIFFERENCE OF COEFFICIENT OF VARIATION Y1 Y2  **
           ************************************************************
      
      
     THE COMPUTED VALUE OF THE CONSTANT A             = -0.85294247E-03
      
      
           ***************************************************************
           **  TABULATE DIFFERENCE OF COEFFICIENT OF VARIATION Y1 Y2 X  **
           ***************************************************************
      
      
                     *    Y1       AND Y2
         X           *    DIFFERENCE OF COEFFICIENT OF V
     **********************************************
         1.00000     *   -0.401654E-01
         2.00000     *   -0.263285E-01
         3.00000     *   -0.119178E-01
      
           GROUP-ID AND STATISTIC WRITTEN TO FILE DPST1F.DAT
        
    plot generated by sample program plot generated by sample program

Date created: 3/27/2003
Last updated: 4/4/2003
Please email comments on this WWW page to alan.heckert@nist.gov.