AS/A2 Stats 1 Stats 2

S3 Topic 4: Goodness of fit and contingency tables
Fitting a Poisson distribution 2
In this version you will choose as part of your hypothesis the value of l. Enter some figures (each should be greater than 5 but definitely bigger than 1) for Observed data in the top row of this table. Choose a vlaue for l. The Expected data is then found along with the calculation of S[O-E]²/E. H0: P(l) is a suitable model for the observed data H1: P(l) is not a suitable model for the observed data If S[O-E]²/E is greater than 15.507 then you can be 95% certain that your Observed data is not, in fact, from the Poisson distribution P(l).

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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