AS/A2 Stats 1 Stats 2

S3 Topic 4: Goodness of fit and contingency tables
Fitting a Poisson distribution 1
Enter some figures (each should be greater than 5 but definitely bigger than 1) for Observed data in the top row of this table. An estimate of the mean l of an assumed Poisson distribution P(l) is found, together with the Expected data and the calculation of S[O-E]²/E. H0: A Poisson distribution is a suitable model for the observed data H1: A Poisson distribution is not a suitable model for the observed data If S[O-E]²/E is greater than 14.067 then you can be 95% certain that your Observed data is not, in fact, from a Poisson distribution.

x	0	1	2	3	4	5	6	7	8
Observed data
l =
Expected data
[O-E]²/E =
S[O-E]²/E =

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