David Orton wrote:
> Whether the data are at the taxon or the element level, the arguments
> surrounding NISP and MNE/MAU are still entirely relevant.
Surely whether they are relevant depends on the question that is being
asked, which here is about "differences in element frequencies between
the two [stratigraphic] units". If the question about is simply about
whether there is a difference in the proportions of recovered material,
then NISP and chi-squared (or Fisher's exact) test are sufficient: they
test whether the proportions in two assemblages are within the expected
random variation after two sets of animals have been subject to the same
butchery, taphonomic and identification processes. MNE and MAU are
derived measures that attempt to account for differing taphonomic
processes, including fragmentation, and as has been noted in this
discussion their statistical properties are not well understood, but I
am not clear whether they are relevant.
Andrew
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Dr. Andrew Millard [log in to unmask]
Durham University
Senior Lecturer in Archaeology Tel: +44 191 334 1147
Deputy Director of Combined Honours Tel: +44 191 334 3006
Archaeology: http://www.dur.ac.uk/archaeology/
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Personal webpage: http://www.dur.ac.uk/a.r.millard/
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