DIFFERENCE OF HARMONIC MEAN

DIFFERENCE OF HARMONIC MEAN (LET)

Let Subcommand

Compute the difference between the harmonic means for two response variables.

The harmonic mean is defined as:
\( \mbox{HM} = \frac{n} {\sum_{i=1}^{n}{1/X_{i}}} \)

For the differeence of harmonic means, the harmonic mean is computed for each of two samples then their difference is taken.

LET <par> = DIFFERENCE OF HARMONIC MEAN <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 harmonic means is stored;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.

LET A = DIFFERENCE OF HARMONIC MEAN Y1 Y2
LET A = DIFFERENCE OF HARMONIC MEAN Y1 Y2 SUBSET X > 1

Dataplot statistics can be used in a number of commands. For details, enter
HELP STATISTICS

None

None

HARMONIC MEAN	= Compute the harmonic mean.
DIFFERENCE OF GEOMETRIC MEAN	= Compute the difference of geometric means.
DIFFERENCE OF MEAN	= Compute the difference of means.
DIFFERENCE OF MEDIAN	= Compute the difference of medians.
DIFFERENCE OF TRIMMED MEAN	= Compute the difference of trimmed means.
DIFFERENCE OF MIDMEAN	= Compute the difference of midmeans.
DIFFERENCE OF BIWEIGHT LOCATION	= Compute the difference of biweight locations.
STATISTICS PLOT	= Generate a statistic versus subset plot.
BOOTSTRAP PLOT	= Generate a bootstrap plot.
TABULATE	= Perform a tabulation for a specified statistic.

Data Analysis

2003/03

SKIP 25 
READ IRIS.DAT Y1 TO Y4 X 
. 
LET A = DIFFERENCE OF HARMONIC MEAN Y1 Y2 
TABULATE DIFFERENCE OF HARMONIC MEAN Y1 Y2 X 
. 
XTIC OFFSET 0.2 0.2
X1LABEL GROUP ID
Y1LABEL DIFFERENCE OF HARMONIC MEAN
CHAR X 
LINE BLANK 
DIFFERENCE OF HARMONIC MEAN PLOT Y1 Y2 X 
CHAR X ALL 
LINE BLANK ALL 
BOOTSTRAP DIFFERENCE OF HARMONIC MEAN PLOT Y1 Y2 X  
    

Dataplot generates the following output.

       *************************************************
       **  LET A = DIFFERENCE OF HARMOMIC MEAN Y1 Y2  **
       *************************************************
  
  
 THE COMPUTED VALUE OF THE CONSTANT A             =  0.27330902E+01
  
  
       ****************************************************
       **  TABULATE DIFFERENCE OF HARMOMIC MEAN Y1 Y2 X  **
       ****************************************************
  
  
                 *    Y1       AND Y2
     X           *    DIFFERENCE OF HARMONIC MEANS
 **********************************************
     1.00000     *     1.59614
     2.00000     *     3.15893
     3.00000     *     3.58727
  
       GROUP-ID AND STATISTIC WRITTEN TO FILE DPST1F.DAT