#1
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Help Needed on Stats Q
Hi,
I'm having a really hard time solving this question. Any help would be greatly appreciated. "Airborne spores produce tiny mould colonies on gelatin plates in a laboratory. The many plates average 3 colonies per plate. What fraction of plates contains exactly 3 colonies? If the average number of colonies is some large integer m, what fraction of plates contains exactly m colonies?" Thanks, |
#2
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Re: Help Needed on Stats Q
Looks like a Poisson distribtuion to me.
P(k,m) = [exp(-m) m^k]/k! is the probability that there are exactly k occurances when m is the expected number of occurances (the average in your problem). I think. I'm not a statistician. |
#3
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Re: Help Needed on Stats Q
I thought that might be the case but it just seemed too easy. So since for the 1st part k = 3 and m = 3, P(3,3) = [exp(-3)3^3) / 3! and for the 2nd, P(m,m) = exp(-m)m^m / m! ?
I'm not very good at stats but I have to take this course b/c it's a prerequisite for some other course... help |
#4
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Re: Help Needed on Stats Q
Looks right to me.
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#5
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Re: Help Needed on Stats Q
thanks for the help borodog.
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