Example of a comparing probability distribution parameters
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Suppose you are analyzing the rate at which bulbs on a piece of machinery tend to burn out. You think a Weibull distribution might model burn-out times well. Use Probability Distribution Plot and your extensive process knowledge to select a shape parameter.

1    Choose Graph > Probability Distribution Plot.

2    Choose Vary Parameters, then click OK.

3    From Distribution, choose Weibull.

4    In Shape, type 1 1.5 2 2.5 3 3.5.

5    In Scale, type 1.

6    Click Multiple Graphs.

7    Under Show Distributions, choose In separate panels of the same graph.

8    Click OK in each dialog box.

Graph window output

Interpreting the results

In your experience, burn-outs tend to increase fairly steadily for a time and then taper off slowly. There are always a few bulbs that last longer than expected. In your opinion, this is captured very well by the Weibull distribution with a shape of 2.