ministat1

Usage

Overview

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:

-A

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

-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. The default is the terminal width, or 74 if standard output is not a terminal.

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.