Question

The number of calls arriving at a switchboard from noon to 1 p.m. during the business days Monday through Friday is monitored for six weeks (i.e. 30 days). Let X be defined as the number of calls during that one-hour period. The relative frequency of calls was recorded and reported as:

Values 5 6 8 9 10 11 12 13 14 15

Rel. Freq. 0.067 0.067 0.100 0.133 0.200 0.133 0.133 0.067 0.033 0.067

Does the assumption of a Poisson distribution seem appropriate as a probability model for these data? Perform a goodness-of-fit procedure with

a-0.05

Note: Please combine cells to the following categories: 7 or less, 8, 9, 10, 11, 12 or more.

(a) Calculate the test statistic $\chi _{0}^2$ Round your answer to two decimal places (e.g. 98.76).

Answer 1