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Homework Statement
Hi everybody! In the context of a physics experiment about radioactivity, I am asked to perform two distributions (poisson and normal) and run a chisquare test for both of them in order to define which one is the most adapted to the histogram (see attached picture).
Homework Equations
##\chi^2 = \sum \frac{(k_j(x) n \cdot P_j)^2}{n \cdot P_j}##
The Attempt at a Solution
So I've used the equation above and got for the Poisson distribution ##\chi^2 = 13.992##. How do I interpret this result? I've got 11 degrees of freedom (13 bins  1  1 parameter) so I looked in that table: http://passel.unl.edu/Image/NamuthCovertDeana956176274/chisqaure distribution table.PNG
and I see that ##\alpha \approx .25##. What does that mean? Is that good/bad? With this calculator: http://stattrek.com/onlinecalculator/chisquare.aspx
I've got for pvalue .77, which seems to be ##1 \alpha##. I'm just not sure just what to think about those numbers.
Thanks a lot in advance for your answers.
Julien.
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