xref: /freebsd/usr.bin/ministat/ministat.1 (revision 7776d3ccd16ec8fd78db34083eb182c2a2d18e26)
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.\" $FreeBSD$
27.\"
28.Dd November 10, 2012
29.Dt MINISTAT 1
30.Os
31.Sh NAME
32.Nm ministat
33.Nd statistics utility
34.Sh SYNOPSIS
35.Nm
36.Op Fl Anqs
37.Op Fl C Ar column
38.Op Fl c Ar confidence_level
39.Op Fl d Ar delimiter
40.Op Fl w Op width
41.Op Ar
42.Sh DESCRIPTION
43The
44.Nm
45command calculates fundamental statistical properties of numeric data
46in the specified files or, if no file is specified, standard input.
47.Pp
48The options are as follows:
49.Bl -tag -width Fl
50.It Fl A
51Just report the statistics of the input and relative comparisons,
52suppress the ASCII-art plot.
53.It Fl n
54Just report the raw statistics of the input, suppress the ASCII-art plot
55and the relative comparisons.
56.It Fl q
57Suppress printing of summary statistics and data-set names; typically for use
58alongside
59.Fl n .
60.It Fl s
61Print the average/median/stddev bars on separate lines in the ASCII-art
62plot, to avoid overlap.
63.It Fl C Ar column
64Specify which column of data to use.
65By default the first column in the input file(s) are used.
66.It Fl c Ar confidence_level
67Specify desired confidence level for Student's T analysis.
68Possible values are 80, 90, 95, 98, 99 and 99.5 %
69.It Fl d Ar delimiter
70Specifies the column delimiter characters, default is SPACE and TAB.
71See
72.Xr strtok 3
73for details.
74.It Fl w Ar width
75Width of ASCII-art plot in characters.
76The default is the terminal width, or 74 if standard output is not a
77terminal.
78.El
79.Pp
80A sample output could look like this:
81.Bd -literal -offset indent
82  $ ministat -s -w 60 iguana chameleon
83  x iguana
84  + chameleon
85  +------------------------------------------------------------+
86  |x      *  x            *      +              + x           +|
87  | |________M______A_______________|                          |
88  |             |________________M__A___________________|      |
89  +------------------------------------------------------------+
90      N        Min        Max     Median        Avg       Stddev
91  x   7         50        750        200        300    238.04761
92  +   5        150        930        500        540    299.08193
93  No difference proven at 95.0% confidence
94.Ed
95.Pp
96If
97.Nm
98tells you, as in the example above, that there is no difference
99proven at 95% confidence, the two data sets you gave it are for
100all statistical purposes identical.
101.Pp
102You have the option of lowering your standards by specifying a
103lower confidence level:
104.Bd -literal -offset indent
105  $ ministat -s -w 60 -c 80 iguana chameleon
106  x iguana
107  + chameleon
108  +------------------------------------------------------------+
109  |x      *  x            *      +              + x           +|
110  | |________M______A_______________|                          |
111  |             |________________M__A___________________|      |
112  +------------------------------------------------------------+
113      N        Min        Max     Median        Avg       Stddev
114  x   7         50        750        200        300    238.04761
115  +   5        150        930        500        540    299.08193
116  Difference at 80.0% confidence
117        240 +/- 212.215
118        80% +/- 70.7384%
119        (Student's t, pooled s = 264.159)
120.Ed
121.Pp
122But a lower standard does not make your data any better, and the
123example is only included here to show the format of the output when
124a statistical difference is proven according to Student's T method.
125.Sh SEE ALSO
126Any mathematics text on basic statistics, for instances Larry Gonicks
127excellent "Cartoon Guide to Statistics" which supplied the above example.
128.Sh HISTORY
129The
130.Nm
131command was written by Poul-Henning Kamp out of frustration
132over all the bogus benchmark claims made by people with no
133understanding of the importance of uncertainty and statistics.
134.Pp
135From
136.Fx 5.2
137it has lived in the source tree as a developer tool, graduating
138to the installed system from
139.Fx 8.0 .
140