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 December 20, 2007 29.Dt MINISTAT 1 30.Os 31.Sh NAME 32.Nm ministat 33.Nd statistics utility 34.Sh SYNOPSIS 35.Nm 36.Op Fl ns 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 n 51Just report the raw statistics of the input, suppress the ASCII-art plot 52and the relative comparisons. 53.It Fl s 54Print the average/median/stddev bars on separate lines in the ASCII-art 55plot, to avoid overlap. 56.It Fl C Ar column 57Specify which column of data to use. 58By default the first column in the input file(s) are used. 59.It Fl c Ar confidence_level 60Specify desired confidence level for Student's T analysis. 61Possible values are 80, 90, 85, 98, 99 and 99.5 % 62.It Fl d Ar delimiter 63Specifies the column delimiter characters, default is SPACE and TAB. 64See 65.Xr strtok 3 66for details. 67.It Fl w Ar width 68Width of ASCII-art plot in characters, default is 74. 69.El 70.Pp 71A sample output could look like this: 72.Bd -literal -offset indent 73 $ ministat -s -w 60 iguana chameleon 74 x iguana 75 + chameleon 76 +------------------------------------------------------------+ 77 |x * x * + + x +| 78 | |________M______A_______________| | 79 | |________________M__A___________________| | 80 +------------------------------------------------------------+ 81 N Min Max Median Avg Stddev 82 x 7 50 750 200 300 238.04761 83 + 5 150 930 500 540 299.08193 84 No difference proven at 95.0% confidence 85.Ed 86.Pp 87If 88.Nm 89tells you, as in the example above, that there is no difference 90proven at 95% confidence, the two data sets you gave it are for 91all statistical purposes identical. 92.Pp 93You have the option of lowering your standards by specifying a 94lower confidence level: 95.Bd -literal -offset indent 96 $ ministat -c 80 iguana chameleon 97 x iguana 98 + chameleon 99 +------------------------------------------------------------+ 100 |x * x * + + x +| 101 | |________M______A_______________| | 102 | |________________M__A___________________| | 103 +------------------------------------------------------------+ 104 N Min Max Median Avg Stddev 105 x 7 50 750 200 300 238.04761 106 + 5 150 930 500 540 299.08193 107 Difference at 80.0% confidence 108 240 +/- 212.215 109 80% +/- 70.7384% 110 (Student's t, pooled s = 264.159) 111.Ed 112.Pp 113But a lower standard does not make your data any better, and the 114example is only included here to show the format of the output when 115a statistical difference is proven according to Student's T method. 116.Sh SEE ALSO 117Any mathematics text on basic statistics, for instances Larry Gonicks 118excellent "Cartoon Guide to Statistics" which supplied the above example. 119.Sh HISTORY 120The 121.Nm 122command was written by Poul-Henning Kamp out of frustration 123over all the bogus benchmark claims made by people with no 124understanding of the importance of uncertainty and statistics. 125.Pp 126From 127.Fx 5.2 128it has lived in the source tree as a developer tool, graduating 129to the installed system from 130.Fx 8.0 . 131