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Dataplot Vol 2 Vol 1

DIFFERENCE OF GEOMETRIC SD

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

      \( \mbox{GSD} = e^{sd(\log{X_i})} \)

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

Syntax:
    LET <par> = DIFFERENCE OF GEOMETRIC 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 geometric standard deviations is stored;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = DIFFERENCE OF GEOMETRIC SD Y1 Y2
    LET A = DIFFERENCE OF GEOMETRIC SD Y1 Y2 SUBSET X > 1
Note:
    Dataplot statistics can be used in a number of commands. For details, enter

Default:
    None
Synonyms:
    None
Related Commands: Applications:
    Data Analysis
Implementation Date:
    2003/03
Program:
    SKIP 25  
    READ IRIS.DAT Y1 TO Y4 X  
    .  
    LET A = DIFFERENCE OF GEOMETRIC SD Y1 Y2  
    TABULATE DIFFERENCE OF GEOMETRIC SD Y1 Y2 X  
    .  
    XTIC OFFSET 0.2 0.2 
    X1LABEL GROUP ID 
    Y1LABEL DIFFERENCE OF GEOMETRIC SDS 
    CHAR X  
    LINE BLANK  
    DIFFERENCE OF GEOMETRIC SD PLOT Y1 Y2 X  
    . 
    CHAR X ALL  
    LINE BLANK ALL  
    BOOTSTRAP DIFFERENCE OF GEOMETRIC SD PLOT Y1 Y2 X   
        
    Dataplot generated the following output.
           ************************************************
           **  LET A = DIFFERENCE OF GEOMETRIC SD Y1 Y2  **
           ************************************************
      
      
     THE COMPUTED VALUE OF THE CONSTANT A             = -0.21327734E-02
      
      
           ***************************************************
           **  TABULATE DIFFERENCE OF GEOMETRIC SD Y1 Y2 X  **
           ***************************************************
      
      
                     *    Y1       AND Y2
         X           *    DIFFERENCE OF GEOMETRIC SD
     **********************************************
         1.00000     *   -0.462339E-01
         2.00000     *   -0.331452E-01
         3.00000     *   -0.122206E-01
      
           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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