U WI Statistics Minitab Guide

Minitab is a versatile statistical processing language that is used in many courses taught in the U WI Statistics Department. This document is adapted from Stat 1000: Statistics Computer Handbook. Return to U WI Statistics Computing Facilities

Getting Started

Before using Minitab, you will need to know how to communicate with the computer. The beginning part of this document should provide enough information for most beginning use. After you have logged on and have the system prompt (%) you can call Minitab by simply typing: 
	% minitab
The Minitab processor will respond with something like this: 
	MINITAB RELEASE 82.1 *** COPYRIGHT - MINITAB, INC. 1983	 
	AUG. 29, 1984 *** Univ. of Wisconsin, Statistics - Instructional
	STORAGE AVAILABLE 50000
	There is HELP on new features of Rel. 82.1.  Type NEWS for details.
	MTB >
The prompt MTB > indicated that Minitab is ready to accept a line of input. After it processes the line you enter, Minitab prints the prompt again to indicated that it is ready for the next line. In the examples which follow the essential Minitab key words will be printed in italics. This is for emphasis only.

When you are finished using Minitab, type: 

	% stop
The screen than displays these messages: 
	*** MINITAB *** STATISTICS DEPT * PENN STATE UNIV> * RELEASE 82.1 *
	STORAGE AVAILABLE 50000
	%
If you have finished with your computing session, you can log-off the computer by typing 
	% logout

Minitab Commands

Minitab stores data and results in an area called a worksheet. The worksheet is an array that can be from 1 to 200 columns wide and contain at most 50000 items. (The size of the worksheet can be varied, but for most class applications 50000 items is more than sufficient)

Data can be read into Minitab in a variety of ways. The easiest is to use the read or set command to enter data at your terminal. read and set, along with other Minitab commands are described in the Minitab Reference Manual. Often, however, the data are already in a file. In this case, use one the following methods to input the data:

If your data are in free format (the values are separated by commas or spaces), you can use the command 

	MTB > read from file 'filespec' into C1-C8
where filespec is the name of a file in the current directory. If the file is in some other directory you will need to give the full path name of the file. For example, a data file for course 572 might be in its data directory, 
	MTB > read from `/u/course/st572-1/data/crane.dat' into C1-C3
If your data are formated, you can use the command: 
	MTB > fred `filespec' into C1-C9
fread prompts you for a Fortran format, which you enter, parentheses and all, as if it followed the keyword FORMAT in a Fortran program. You can use F.E. A, and X formats. To Read an integer with 14 format, use F4.0. For instance, if you use the command 
	MTB > fread `minfor' into C1, C2-C6
then an appropriate response to the prompt 
	ENTER FORMAT
	CONT >
could be 
	(F4.0,3x,5f8.4)
The save and retrieve commands will (respectively) save an restore the contents of a workspace. Thus if you are halfway through a problem and find you have to leave you can save the workspace via: 
	save `filename'
and then exist from Minitab. Later you could continue your Minitab session and restore the worksheet with 
	MTB > retrieve `filename'
Note that Minitab actually stores the contents of the worksheet in a local file called filename .MTW. (Minitab automatically adds the .MTW extension).

Hard Copy Output

There are at least two ways of saving the output from Minitab in a file for later printing on a printer. The simplest way is to use Minitab's outfile command so selectively save those parts of the output that you are interested in. An alternative is to use the UNIX script command to make a copy of the entire Minitab session, and then later edit the session for presentation. It is certainly much easier to use the outfile method, and that is what is described here. (For information on the script program, see the manual entry.)

Using the outfile command, selected pieces of output can be saved in a file. This file can then be edited and/or printed. For example, the following sequence of Minitab commands would save the output from the regression and info commands in the file save.LIS. 

	MTB > outf 'save'
	MTB > regr Cl 1 C2
	MTB > outf
	.
	.
	.
	MTB > outf 'save'
	MTB > info
	MTB > outf
The first outf command diverts the output to the file save.LIS (the .LIS is automatically added by Minitab). The next outf command restores output to the terminal, and so on. One can save output in several different files by giving outf different arguments. A null argument to outf always results in output reverting to the terminal.

The usual way of proceeding would be to execute a Minitab command and if the output looks interesting, saving the output by turning on outfile, re-executing the command, and then turning off outf. To actually get a hardcopy of your file then you have to stop Minitab and use the lpr or print commands (as described in the UNIX Guide) to send the file to the line printed. That is, type 

	% lpr save.LIS
or 
	% print save.LIS
Remember that it is always a good idea to preview your listing file to make sure you have what you want. Please conserver paper!

Datasets for Minitab Examples

Most of the data sets used as examples in the Minitab Student Handbook are stored in the directory /usr/stat/lib/minitab/handbook. You can use the retrieve command to put them into your workspace. For example to get the cartoon data you would say; 
	MTB > retr '/usr/stat/lib/minitab/handbook/cartoon'
Currently the following data sets are available in /usr/stat/lib/minitab/handbook: 
	acid1      choleste   ga         meatloaf   radon
	acid2      cities     gb         peru       restrnt
	alfalfa    employ     grades     plywood    schools
	azalea     fa         hcc        potato     trees
	cartoon    fabric     lake       pres       twain
	cholestc   furnace    maple      pulse
If you actually want to look at the raw data, they are available in the following files in /usr/stat/lib/minitab/handbook: 
acid1.DAT      choleste.DAT   ga.DAT         meatloaf.DAT   radon.DAT
acid2.DAT      cities.DAT     gb.DAT         peru.DAT       restrnt.DAT
alfalfa.DAT    employ.DAT     grades.DAT     plywood.DAT    schools.DAT
azalea.DAT     fa.DAT         hcc.DAT        potato.DAT     trees.DAT
cartoon.DAT    fabric.DAT     lake.DAT       pres.DAT       twain.DAT
cholestc.DAT   furnace.DAT    maple.DAT      pulse.DAT
Note that the ending .DAT must be capitalized.

More Information

An up to date description of the current version of Minitab is available with the help command.

Many of the features of Minitab, along with explanatory text and examples, are documented in the Minitab Student Handbook by TA Ryan, et al., Duxbury Press 1985. Copies of the Handbook are available for checkout at the Kurt F Wendt Library, or for purchase in the DoIT lobby.

A more complete description of Minitab commands is in the Minitab Reference Manual. This manual does not contain as much supporting text and examples as the Handbook but it includes descriptions of features not included in the Handbook. The reference manual is available for checkout at the Kurt F Wendt Library, or for purchase in the DoIT lobby. Again, be aware that this document might not exactly describe the implementation on our computer. DoIT also sells a Minitab Quick Reference Card. This card contains a brief description of Minitab commands.

Last modified: Sun Feb 26 17:21:55 1995 by Stat Www (statwww@stat.wisc.edu)