xref: /freebsd/usr.bin/ministat/ministat.1 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)
1.\"
2.\" Copyright (c) 2007 Poul-Henning Kamp
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions and the following disclaimer.
10.\" 2. Redistributions in binary form must reproduce the above copyright
11.\"    notice, this list of conditions and the following disclaimer in the
12.\"    documentation and/or other materials provided with the distribution.
13.\"
14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24.\" SUCH DAMAGE.
25.\"
26.Dd November 10, 2012
27.Dt MINISTAT 1
28.Os
29.Sh NAME
30.Nm ministat
31.Nd statistics utility
32.Sh SYNOPSIS
33.Nm
34.Op Fl Anqs
35.Op Fl C Ar column
36.Op Fl c Ar confidence_level
37.Op Fl d Ar delimiter
38.Op Fl w Op width
39.Op Ar
40.Sh DESCRIPTION
41The
42.Nm
43command calculates fundamental statistical properties of numeric data
44in the specified files or, if no file is specified, standard input.
45.Pp
46The options are as follows:
47.Bl -tag -width Fl
48.It Fl A
49Just report the statistics of the input and relative comparisons,
50suppress the ASCII-art plot.
51.It Fl n
52Just report the raw statistics of the input, suppress the ASCII-art plot
53and the relative comparisons.
54.It Fl q
55Suppress printing of summary statistics and data-set names; typically for use
56alongside
57.Fl n .
58.It Fl s
59Print the average/median/stddev bars on separate lines in the ASCII-art
60plot, to avoid overlap.
61.It Fl C Ar column
62Specify which column of data to use.
63By default the first column in the input file(s) are used.
64.It Fl c Ar confidence_level
65Specify desired confidence level for Student's T analysis.
66Possible values are 80, 90, 95, 98, 99 and 99.5 %
67.It Fl d Ar delimiter
68Specifies the column delimiter characters, default is SPACE and TAB.
69See
70.Xr strtok 3
71for details.
72.It Fl w Ar width
73Width of ASCII-art plot in characters.
74The default is the terminal width, or 74 if standard output is not a
75terminal.
76.El
77.Pp
78A sample output could look like this:
79.Bd -literal -offset indent
80  $ ministat -s -w 60 iguana chameleon
81  x iguana
82  + chameleon
83  +------------------------------------------------------------+
84  |x      *  x            *      +              + x           +|
85  | |________M______A_______________|                          |
86  |             |________________M__A___________________|      |
87  +------------------------------------------------------------+
88      N        Min        Max     Median        Avg       Stddev
89  x   7         50        750        200        300    238.04761
90  +   5        150        930        500        540    299.08193
91  No difference proven at 95.0% confidence
92.Ed
93.Pp
94If
95.Nm
96tells you, as in the example above, that there is no difference
97proven at 95% confidence, the two data sets you gave it are for
98all statistical purposes identical.
99.Pp
100You have the option of lowering your standards by specifying a
101lower confidence level:
102.Bd -literal -offset indent
103  $ ministat -s -w 60 -c 80 iguana chameleon
104  x iguana
105  + chameleon
106  +------------------------------------------------------------+
107  |x      *  x            *      +              + x           +|
108  | |________M______A_______________|                          |
109  |             |________________M__A___________________|      |
110  +------------------------------------------------------------+
111      N        Min        Max     Median        Avg       Stddev
112  x   7         50        750        200        300    238.04761
113  +   5        150        930        500        540    299.08193
114  Difference at 80.0% confidence
115        240 +/- 212.215
116        80% +/- 70.7384%
117        (Student's t, pooled s = 264.159)
118.Ed
119.Pp
120But a lower standard does not make your data any better, and the
121example is only included here to show the format of the output when
122a statistical difference is proven according to Student's T method.
123.Sh SEE ALSO
124Any mathematics text on basic statistics, for instances Larry Gonicks
125excellent "Cartoon Guide to Statistics" which supplied the above example.
126.Sh HISTORY
127The
128.Nm
129command was written by Poul-Henning Kamp out of frustration
130over all the bogus benchmark claims made by people with no
131understanding of the importance of uncertainty and statistics.
132.Pp
133From
134.Fx 5.2
135it has lived in the source tree as a developer tool, graduating
136to the installed system from
137.Fx 8.0 .
138