Dear all
I got this request from a friend:
In theory, the more fish there is on a reef, the more species are
expected
to exist by chance (if fish of different species have a random chance of
joining the community). My own hypothesis is different so I am trying to
disprove the hypothesis that different fish species appear at random in
a
fish community.
So he took 150 samples, each containing up to 12 fishes.
For example he has (out of a maximum of 7 species)
sample 1 6 fish 2 species
sample 2 4 fish 1 species
sample 3 8 fish 5 species
He needs to determine the expected number of species in each sample or
the probability of observing sample 1.
According to me (and him) he is testing the hypothesis prob(getting
species i)=1/7. So in principle in a sample of 6, he should get 6
species.
This seems intuitively wrong.
Can anyone help please?
Coomaren
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Dr Coomaren P Vencatasawmy
Senior Research Fellow
Spatial Modelling Centre (SMC)
P.O. Box 839
S-981 28
Kiruna
Sweden
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Telephone: 46 980 67013
Fax : 46 980 67190
"Perfection is achieved, not when there is nothing more to add, but when
there is nothing left to take away." - Antoine de Saint Exupery
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