Fit of ordination axes always given?
Dear group, I have used the as.mlm.cca(vegan) function to derive statistical measures for the goodness of fit of my environmental variables and the ordination axes of an RDA. I prepared a manuscript in which I used spectral indices (NDVI etc.) as environmental variables in a RDAand have now received answers from a reviewer in which he/she states that: /'Ordination axes that show a good statistical fit with the spectral indices' - all ordination axes are linearly related to the predictors - this is forced by the CCA or RDA method itself (see l. 203 ff). Thus, statistical fit is always given. / I agree that all ordination axes are linearly related to the predictors, but I refuse to believe that therefore a good (!) 'statistical fit is always given'. It might be also pretty poor, in my opinion. Am I wrong? I would be very grateful if someone could comment on that, thank you in advance, Jens //
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Dipl.Biol. Jens Oldeland
University of Hamburg
Biocentre Klein Flottbek and Botanical Garden
Ohnhorststr. 18
22609 Hamburg,
Germany
Tel: 0049-(0)40-42816-407
Fax: 0049-(0)40-42816-543
Mail: Oldeland at botanik.uni-hamburg.de
Jens.Oldeland at DLR.de (for attachments > 2mb!!)
http://www.biologie.uni-hamburg.de/bzf/fbda005/fbda005.htm
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