Minitab

Minitab is an easy-to-use general purpose statistical computing system. It is a flexible and powerful tool that has been designed especially for students and researchers who have no previous experience with computers. It is designed primarily for moderate sized data sets which can be stored in main memory. On UNIX, Minitab is run on an interactive basis. It consists of a worksheet of rows and columns to store data. Minitab has an on-line HELP facility, which gives short explanations of commands and syntax. The Minitab program recognizes about 150 commands. The most commonly used commands will be described below.

Throughout this handout the prompts and responses typed by the computer will be typed in plain text, like this. The responses from you, the user, will be typed in bold type, like this.

Invoking Minitab:

Log in on the computer as you normally would. At the 'cda.morris.umn.edu' prompt enter the command MINITAB and press ENTER. You will then receive a brief commercial for MINITAB and you will be off and ready to begin. Minitab uses MTB> as its prompt.

Exiting Minitab:

STOP ends the current session.

General Information:

• In the examples below K is a constant, C is a column number, E is either a constant or a column number.
• For most Minitab commands you need only enter the first 4 characters of a command, followed by the column number or constant. In the examples below only the bolded portions need to be entered by the user.
• Each command must start on a separate line.
• Commands cannot appear within a number e.g., you should type 1241 instead of 1,241.
• A list of consecutive column numbers (or stored constants or matrices) may be indicated using a dash. Example: READ C2-C4.
• Commands can be continued onto a second line by putting an ampersand ('&') at the end of the first line.
• Columns, stored constants, and matrices can be reused any number of times. When a column number is reused, all previous contents are automatically erased before the new results are stored in memory.
• A column may be given a name by using the command NAME. The name may then be used in place of the column number. Any time a name is used it must be enclosed in single quotes.
• To use a subcommand, end the main command line with a semicolon. The semicolon tells Minitab that there will be a subcommand on the next line. End the last subcommand with a period.

Printing a Minitab Session on Paper:

Note: Type the OUTFILE command at the beginning of your Minitab session or no copy will be made of your Minitab session.

OUTFILE the session in 'filename'. Puts all Minitab output that follows into a computer file at the system level that can be printed after you exit Minitab.

Example:
MTB> OUTFILE 'SOMENAME'
MTB> (other Minitab commands)
MTB> STOP


To print the file after you have "stopped" out of Minitab, type the following command at the 'cda.morris.umn.edu' prompt:

lpr -Pprintquename SOMENAME.LIS

Entering Data:

READ the following data into C,...,C
Note: Data is entered on separate lines which follow a READ or SET command.
Example: MTB> READ C6,C7

SET the following data into column C
Example: MTB> SET C1

END Use this command after you've entered all your data (either with a READ or SET command) and before you use another command.

Printing Data on the Screen within Minitab:

PRINt the data in C,...,C
Example: MTB> PRIN C1

Saving and Retrieving Data:

SAVE the worksheet in 'filename'. (The worksheet will include all data columns, rows, values and titles that have been entered.)
Example: MTB> SAVE 'SOMENAME'
(Creates a VMS file called SOMENAME.MTW)

OUTFILE 'FILENAME' will create a file which is a snapshot of what has occured in your minitab session.

WRITE [to 'filename'] the following data from C,...,C
Example: MTB> WRITE 'SOMENAME' C3,C4
(Saves columns 3 & 4 in a file)

RETRieve the worksheet stored in 'filename'. After using RETRIEVE, the worksheet will contain the same columns it had when SAVE was used to create the file.
Example: MTB> RETR 'MYFILE'

Modifying Data Columns:

INSErt between rows K and K of C,...,C OR into C,...,C (To add data to the end of columns)
Example: MTB> INSERT 3 4 C2
(would insert values which follow between rows 3 & 4 of column 2)

DELEte rows K1,...,Km of C
Example: MTB> DELE 1 C3
(Would delete row 1 from column 3)

LET C (K) = E
Example: MTB> LET C1 (3) = 1.3
(Would replace the value in row 3 of column 1 with the value 1.3)

COPY The following data from one column to another. Can be used with the OMIT subcommand as shown below:
Example: MTB> COPY C1 INTO C2;
SUBC> OMIT 2.
(Would omit row 2 from column 1 and store remainder in column 2.)

Sorting and Numbering:

SORT C,...,C put into C,...,C

RANK the values in C, put ranks into C

Plots and Historgrams:

HISTogram of C,...,C [first midpoint K, interval width K]
Example: MTB> HIST C5

PLOT y in C vs x in C y in C from K to K vs x in C from k to K
Example: MTB> PLOT C7 C8

STEM-and-leaf display of C,...,C
Example: MTB> STEM C3

BOXPlot display of C,...,C
Example: MTB> BOXP C6

ERASE C,...,C

Other Minitab commands can be found in the MINITAB Student Handbook in the User's Room of Computing Services.