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354 Part V: Appendices
Continued
Figure B.13 Minitab display of the pie chart for the data in Example B.9.
Probability Distributions
To calculate various probabilities, select Calc > Probability Distributions from
the command menu and then the probability of choice. This will prompt a dialog
box to appear where the choice of how the probabilities are calculated, that is,
probability density, cumulative probability, or inverse probability can be selected.
Based on the probability distribution being calculated, appropriate parameter
entries need to be made. The choices of probability distribution include uniform,
binomial, t, chi-square, normal, f, Poisson, exponential, and others. We discuss
several of these examples below. The technique for other distributions is quite
similar and self-explanatory.
Normal Distribution. Using Minitab we can calculate three values related to the
normal distribution:
1. Probability density, which means finding an area under the normal
distribution curve
2. Cumulative probability, which means finding an area under the
normal distribution curve below a certain value of x
3. Inverse cumulative probability, which means that the area under
the normal distribution curve below x is given, and we want to find
out the corresponding value of x
To calculate any of the above probabilities proceed as follows. From the menu
bar select Calc > Probability Distributions > Normal. This will prompt a dialog