On 05/15/2013 10:08 PM, Dixon, Mark wrote:
I think there is a type of chi-square analysis that takes into account rank
order levels of one of the categorical variables. Can anyone remember what
this is called? We want to use it in an analysis in which the response
variable is in abundance categories (e.g., 0, 1-10, 11-25..., etc.) and we want
to compare two different treatments. For these data, we don't think it would
be appropriate to just use the midpoint of the range.
If you're using R (and if not, convert before using anything else is
declared statistical apostasy), polr() in the MASS package should do
what you want. "Ordinal regression" is the general term for this sort of
analysis.
Bob
--
Bob O'Hara
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