[Vegan-commits] r2199 - pkg/vegan/inst/doc

[noreply at r-forge.r-project.org]

Author: jarioksa
Date: 2012-05-27 16:55:57 +0200 (Sun, 27 May 2012)
New Revision: 2199

Modified:
   pkg/vegan/inst/doc/FAQ-vegan.texi
Log:
FAQ: some words about local, hybrid and metric scaling and their data size requirements

Modified: pkg/vegan/inst/doc/FAQ-vegan.texi
===================================================================
--- pkg/vegan/inst/doc/FAQ-vegan.texi	2012-05-27 14:47:03 UTC (rev 2198)
+++ pkg/vegan/inst/doc/FAQ-vegan.texi	2012-05-27 14:55:57 UTC (rev 2199)
@@ -382,6 +382,12 @@
 (@code{k}) and with very small data sets you should not use @code{NMDS},
 but rely on metric methods.
 
+It seems that local and hybrid scaling with @code{monoMDS} have similar
+lower limits in practice (although theoretically they could differ).
+However, higher number of dimensions can be used in metric scaling, both
+with @code{monoMDS} and in principal coordinates analysis
+(@code{cmdscale} in @pkg{stats}, @code{wcmdscale} in @pkg{vegan}).
+
 @node Zero dissimilarities in isoMDS, How the RDA results are scaled?, I get zero stress but no convergent solutions in @code{metaMDS}, Ordination
 @section Zero dissimilarities in isoMDS