Re: NANFA-L-- Diversity Indicies

Bruce Stallsmith (fundulus at
Thu, 29 Sep 2005 10:48:45 -0400

For more statistically rigorous and informative index values, check out the
various Hill's diversity numbers, especially the second diversity number
(N2), which is the inverse of Simpson's index. That N2 value gives you the
number of very abundant species, which use can be argued for on a variety of
practical and theoretical grounds. I'm happy to hand out references

--Bruce Stallsmith
biostatistics are king in the Tennessee Valley
Huntsville, AL, US of A

>From: matt ashton <ashtonmj2003 at>
>Reply-To: nanfa-l at
>To: nanfa-l at
>Subject: Re: NANFA-L-- Diversity Indicies
>Date: Thu, 29 Sep 2005 06:44:19 -0700 (PDT)
>I have a copy of the Ohio IBI manual so with the right info, like
>ecoregion, drainage size I could give you a rough score from it. The few
>problems I see using that is 1) im assuming you seined and not
>electroshocked 2) not sampling the entire community, every available
>habitat thing, so its somewhat bias and 3) unless I have missed some of the
>updates alot of the subclassifications of species were incomplete. Usually
>it was for things that were rare or not much known about, which
>coincidentally is usually things that are dependent upon good water quality
>so it would effect your scoring. Some of the major western ohio ecoregions
>go into that area of IN so I think it might cover it, if it didn't it might
>still be applicable or easily adaptable.
>Matt Ashton
>Tenneessee Tech University
>Cookeville TN
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