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Dataplot Vol 2 Vol 1

DIFFERENCE OF RELATIVE SD

Name:
    DIFFERENCE OF RELATIVE SD (LET)
Type:
    Let Subcommand
Purpose:
    Compute the difference between the relative standard deviations for two response variables.
Description:
    The relative standard deviation is:

      \( \mbox{relsd} = \frac{100 s}{|\bar{x}|} \)

    with s and \( \bar{x} \) denoting the standard deviation and mean, respectively.

    Some analysts prefer to call this the percent relative standard deviation and the value obtained without multiplying by 100 the relative standard deviation. If this is your preference, simply divide the obtained value by 100 with the LET command. This differs from the coefficient of variation in that the absolute value of the mean is taken and the value is expressed as a percentage.

    For the difference of relative standard deviations, the relative standard deviation is computed for each of two samples then their difference is taken.

Syntax:
    LET <par> = DIFFERENCE OF RELATIVE SD <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 relative standard deviations is stored;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = DIFFERENCE OF RELATIVE SD Y1 Y2
    LET A = DIFFERENCE OF RELATIVE SD Y1 Y2 SUBSET X > 1

Note:
    Dataplot statistics can be used in a number of commands. For details, enter

Default:
    None
Synonyms:
    DIFFERENCE OF RELATIVE STANDARD DEVIATION is a synonym for DIFFERENCE OF RELATIVE SD.
Related Commands: Applications:
    Data Analysis
Implementation Date:
    2003/03
Program:
    SKIP 25 
    READ IRIS.DAT Y1 TO Y4 X 
    . 
    LET A = DIFFERENCE OF RELATIVE SD Y1 Y2 
    TABULATE DIFFERENCE OF RELATIVE SD Y1 Y2 X 
    . 
    XTIC OFFSET 0.2 0.2 
    X1LABEL GROUP ID 
    Y1LABEL DIFFERENCE OF RELATIVE SD 
    CHAR X 
    LINE BLANK 
    DIFFERENCE OF RELATIVE SD PLOT Y1 Y2 X 
    CHAR X ALL 
    LINE BLANK ALL 
    BOOTSTRAP DIFFERENCE OF RELATIVE SD PLOT Y1 Y2 X  
        
    Dataplot generated the following output.
           ***********************************************
           **  LET A = DIFFERENCE OF RELATIVE SD Y1 Y2  **
           ***********************************************
      
      
     THE COMPUTED VALUE OF THE CONSTANT A             = -0.85294724E-01
      
      
           **************************************************
           **  TABULATE DIFFERENCE OF RELATIVE SD Y1 Y2 X  **
           **************************************************
      
      
                     *    Y1       AND Y2
         X           *    DIFFERENCE OF RELATIVE SD
     **********************************************
         1.00000     *    -4.01654
         2.00000     *    -2.63285
         3.00000     *    -1.19178
      
           GROUP-ID AND STATISTIC WRITTEN TO FILE DPST1F.DAT
        
    plot generated by sample program

    plot generated by sample program

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Date created: 03/27/2003
Last updated: 11/09/2015

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