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StatCalc: Statistical Calculators

PAGE 8 of 12

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Poisson

To analyze the Poisson distribution, enter the expected number of positive outcomes in Expected # of events and the value of positive outcomes you would like to determine the probability of in Observed # of events.

Figure 10.14: Poisson Distribution

The results show that there is a 0.13% chance of having six or more positive outcomes when the expected value is 1.16. Additional percentages are stated for the ranges outlined in the left column of the table.