It is believed that the number of drivers who are ticketed i
It is believed that the number of drivers who are ticketed in an hour for speeding on a particular stretch of highway is a Poisson distribution with a mean of 3.0 per hour. A random sample of 100 hours is selected with the following results:
These data are included in the Final Exam Excel Files under the tab
| Tickets | Frequency | 
| 0 | 5 | 
| 1 | 9 | 
| 2 | 20 | 
| 3 | 18 | 
| 4 | 20 | 
| 5 | 15 | 
| 6 | 4 | 
| 7 | 6 | 
| 8 | 1 | 
| 9 | 2 | 
Solution
For testing whether it is a Poisson
find mean and std dev.
As mean and variance are considerably difference this data does not fit a Poisson model
| Tickets | Frequency | tickets*freq | tickets^2*freq | 
| 0 | 5 | 0 | 0 | 
| 1 | 9 | 9 | 81 | 
| 2 | 20 | 40 | 800 | 
| 3 | 18 | 54 | 972 | 
| 4 | 20 | 80 | 1600 | 
| 5 | 15 | 75 | 1125 | 
| 6 | 4 | 24 | 96 | 
| 7 | 6 | 42 | 252 | 
| 8 | 1 | 8 | 8 | 
| 9 | 2 | 9 | 18 | 
| Total | 100 | 341 | 4952 | 
| Mean | 3.41 | ||
| Variance | 37.8919 | 

