At a local supermarket receiving dock, the number of truck arrivals per day is recorded for 100 days.
(a) Estimate the mean from the sample. (b) Calculate the expected frequencies assuming a Poisson
distribution. Show your calculations in a spreadsheet format. (c) Carry out the chi-square test, combining
end categories as needed to ensure that all expected frequencies are at least five. Show your
degrees of freedom calculation. (d) At α = .05, can you reject the hypothesis that arrivals per day
follow a Poisson process? Trucks
Arrivals per Day at a Loading Dock
Number of Arrivals
0 1 2 3 4 5 6 7 Total
Frequency 4 23 28 22 8 9 4 2 100
The solution provides step by step method for the calculation of goodness fit statistics for chi square test. Formula for the calculation and Interpretations of the results are also included.