Normal probability plots > Normal probability plot in Minitab
How to create a normal probability plot in Minitab
Step 1: Type your data into columns in a Minitab worksheet. Give your variables meaningful names in the first (blank) row (this makes it easier to build the plot when you select a variable name in Step 4).
Step 2: Click “Graph” on the toolbar and then click “Probability plot.”
Step 3: Click the “Single” probability plot image. This is the option you’re likely to use 99% of the time in elementary statistics.
Step 4: Choose a variable name and then click “Select” to move the variable name to the Graph Variables box. If you didn’t name your variables in Step 1, the variable names will be listed as column identifiers (C1, C2 etc.).
Step 5: Click “OK.” Minitab will create a normal probability graph in a new window.
Tip: Make a histogram in minitab to see how well your data fits a normal distribution. Often a normal probability plot will appear to be fairly straight, but it might not be a great match to a bell curve. Checking the histogram first will allow you to see if your data fits a bell curve before you make assumptions about your data using the normal probability plot.
If you prefer an online interactive environment to learn R and statistics, this free R Tutorial by Datacamp is a great way to get started. If you're are somewhat comfortable with R and are interested in going deeper into Statistics, try this Statistics with R track.Comments are now closed for this post. Need help or want to post a correction? Please post a comment on our Facebook page and I'll do my best to help!