Minitab - Frequency Distributions

The data for the ungrouped frequency distribution is in a column given the name "X" and the data for the grouped frequency distribution is in a column given the name "Y". The Minitab Worksheet is available.

Use the "Tally Individual Variables..." command off of the "Stat, Tables" menu. That is:

That will take you to the following dialog box:

Type the relevant variable(s) in the box (or double click them from the left hand menu) and make sure all of the display option boxes are checked. The output will look like this:

 Tally for Discrete Variables: X ``` X Count CumCnt Percent CumPct 2 3 3 15.00 15.00 4 3 6 15.00 30.00 5 4 10 20.00 50.00 6 5 15 25.00 75.00 7 5 20 25.00 100.00 N= 20```

Here we have to use Minitab's graphs to get what we want. Use the "Histogram..." command off of the "Graph" menu. That is:

That will take you to the following dialog box:

Choose "Simple". Then you will see the following dialog box:

Type the relevant variable(s) in the box (or double click them from the left hand menu). Then press "OK" and you will see a graph that shows the frequencies.

However, the midpoints are not correct. To solve this problem, double click the X axis. This will take you to the following dialog box:

Then you need to click on the third tab that says "binning", and you will see this dialog box:

Now, Choose the "Midpoint/Cutpoint positions" and type in the values you want for the the midpoints. The output will look like this (which mirrors our in class computations):

If you want the percents, cumulative frequencies, or cumulative percents, double click the Y axis which will lead to this dialog box:

• Checking the Percent Radio button will give you percents on the Y axis.
• Checking the Frequency Radio button along with the "Accumulate values across bins" box will give you Cumulative Frequecies.
• Checking the Percent Radio button along with the "Accumulate values across bins" box will give you Cumulative Percents.