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Chapter 13: Chi Square test

J

jensen

Member
Hi

In Chapter 12, the example applying ChiSq test to graduation A and B (page 30) uses the test statistic of the form:

Sum {(Actual - Expected)^2}/Expected.

In Chapter 13 (section 5.2 pg 23), to test the fit of graduated rates the test statistic there is:

Sum {standardised deviations, z_i}^2

There is no difference between the two above if the Poisson model was used, but not so for the Binomial model since the variance have an additional (1-q) term. One can argue that q is approx 0, hence negligible, but it bugs me that the notes are not consistent.

In the exam, can we assume the q is approx 0, hence the first form of ChiSq test statistic applies?
 
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