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MINISTAT(1)               BSD General Commands Manual              MINISTAT(1)

NAME
     ministat -- statistics utility

SYNOPSIS
     ministat [-ns] [-C column] [-c confidence_level] [-d delimiter]
              [-w [width]] [file ...]

DESCRIPTION
     The ministat command calculates fundamental statistical properties of
     numeric data in the specified files or, if no file is specified, standard
     input.

     The options are as follows:

     -n          Just report the raw statistics of the input, suppress the
                 ASCII-art plot and the relative comparisons.

     -s          Print the average/median/stddev bars on separate lines in the
                 ASCII-art plot, to avoid overlap.

     -C column   Specify which column of data to use.  By default the first
                 column in the input file(s) are used.

     -c confidence_level
                 Specify desired confidence level for Student's T analysis.
                 Possible values are 80, 90, 95, 98, 99 and 99.5 %

     -d delimiter
                 Specifies the column delimiter characters, default is SPACE
                 and TAB.  See strtok(3) for details.

     -w width    Width of ASCII-art plot in characters, default is 74.

     A sample output could look like this:

             $ ministat -s -w 60 iguana chameleon
             x iguana
             + chameleon
             +------------------------------------------------------------+
             |x      *  x            *      +              + x           +|
             | |________M______A_______________|                          |
             |             |________________M__A___________________|      |
             +------------------------------------------------------------+
                 N        Min        Max     Median        Avg       Stddev
             x   7         50        750        200        300    238.04761
             +   5        150        930        500        540    299.08193
             No difference proven at 95.0% confidence

     If ministat tells you, as in the example above, that there is no
     difference proven at 95% confidence, the two data sets you gave it are
     for all statistical purposes identical.

     You have the option of lowering your standards by specifying a lower
     confidence level:

             $ ministat -s -w 60 -c 80 iguana chameleon
             x iguana
             + chameleon
             +------------------------------------------------------------+
             |x      *  x            *      +              + x           +|
             | |________M______A_______________|                          |
             |             |________________M__A___________________|      |
             +------------------------------------------------------------+
                 N        Min        Max     Median        Avg       Stddev
             x   7         50        750        200        300    238.04761
             +   5        150        930        500        540    299.08193
             Difference at 80.0% confidence
                   240 +/- 212.215
                   80% +/- 70.7384%
                   (Student's t, pooled s = 264.159)

     But a lower standard does not make your data any better, and the example
     is only included here to show the format of the output when a statistical
     difference is proven according to Student's T method.

SEE ALSO
     Any mathematics text on basic statistics, for instances Larry Gonicks
     excellent "Cartoon Guide to Statistics" which supplied the above example.

HISTORY
     The ministat command was written by Poul-Henning Kamp out of frustration
     over all the bogus benchmark claims made by people with no understanding
     of the importance of uncertainty and statistics.

     From FreeBSD 5.2 it has lived in the source tree as a developer tool,
     graduating to the installed system from FreeBSD 8.0.

BSD                              June 28, 2010                             BSD

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | HISTORY