Using the Computer and Minitab

This page contains some basic information on how to use the computer, specifically the MINITAB statistics program

At the beginning of each computer session you need to log on:
Turn the computer on
Username: Last six digits of your student ID number
Password: First time you log on leave this blank and then choose your own password
The class webpage is at http://www.math.uprm.edu/wrolke/esma3015

At the end of each session save your work on a floppy disk, close Minitab and Explorer, log off

File Handling:
Getting a MINITAB file: File > Open Project (careful: Project, not Worksheet)
In the Open dialog box click the down arrow on the right of the "look in" box and go to: Rolke$ > 3015

When saving a file click on FiIe > Save Current Project As..
In the Save as.. dialog box click the down arrow on the right of the "save in" box and go to: Floppy (A)

In order to print a graph or the session window click on File > Print
If necessary click on the arrow next to the 'Name' box and change the printer to hpm119

MINITAB 'thinks" in terms of columns, that is all the observations belonging to the same variable go into the same column. Most commands work on all the numbers (words, etc.) in a column

The first row (in gray) is used for column names. This is very important, you should always have a nice descriptive name for your variables (columns)

MINITAB is mostly point-and-click, and you begin by clicking a category on top, just like in most Windows based programs.

Example: As a little exercise consider the WR INC company

What is the mean income of the people working in this company?
Stat > Basic Statistics > Display Descriptive Statistics, Variable= Income
Mean = 39594

What is the mean income of the men and women working in this company?
Stat > Basic Statistics > Display Descriptive Statistics, Variable= Income, By variables=Gender
Female: 39594, Male: 40206

Say we decide that everybody gets an extra $1.50 for every mile they have to drive to work, what would their new income be?
Calc > Calculator, Store in: NewIncome, Expression: 'Income' + 1.5 * 'Distance'

Who is the employee (his/her id) with the highest income?
From the descriptive command above we see that the highest income is $96300. Going through the worksheet we find it belongs to the employee with id 8915 (in row 467)
This makes it a little easier: Calc > Calculator, Store in: c10, Expression: 'Income' = MAX('Income')
This puts a 1 if a person has the highest income, a 0 otherwise, so now we just need to find the 1
Even easier: Data > Sort, Sort columns: ID, By column: Income, check Descending

Draw a scatterplot of Income by Years and Gender