Greetings everyone,
I am running MDS on a very large dataset (12 x 25071 - 12 model runs with 25071
output values each), and also on a very much reduced version of the dataset
(randomly select 1000 of the 25071 output values). I would like to look at
similarities/dissimilarities between the 12 model runs. When I use metaMDS on
the full dataset, I get a warning message:
Warning message:
In metaMDS(MDSdata, distance = "bray", k = 2, autotransform = FALSE) :
Stress is (nearly) zero - you may have insufficient data
I don't think I have insufficient data, with 12 x 25071 data points, and when I
reduce the dataset to only 1000 values per model run (so only 12 x 1000) I
don't get this warning (though the final stress is now only just below 0.2 - my
desired value).
Is this warning because I have insufficient data? Or is it because of the
nature of a large dataset?
I can supply a dataset in .txt format by email, if that would be helpful.
Thanks for your help,
Raeanne
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