similar to: metaMDS

Dear R-community, dear Jari Oksanen! I use metaMDS (package vegan) to calculate NMDS. In a lot of papers I read that it is recommended to use previous best solutions as a new starting configuration to get better results and to avoid local minima. On the help page I found that a previous.best-command is already implemented in metaMDS: metaMDS(comm, distance = "bray", ...,plot = FALSE,

I have looked all over the internet for being able to color sites differently in a plot of an MDS (metaMDS)- I would like to color the different sites in the ordination plot (plot or ordiplot). I have set the matrix up so that my site code is 1 .... 296 (first column). is there a way to make 1-23 blue, 24-40 red etc. thanks Stephen -- Let's not spend our time and resources thinking

Hello, I am using vegan to do an NMDS plot and I would like to suppress the labels for the loading vectors. Is this possible? Alternatively, how can I avoid overlap? Many thanks for the help. Example code: #perform NMDS using metaMDS() function spe.nmds<-metaMDS(data, distance='bray',k=2 , engine = "isoMDS", autotransform=F, trymax=1000) #calculate the loading (i.e.,

Hi Listers, I am trying to reflect a PCA biplot in the x-axis (i.e. PC1) but am not having much success. In theory I believe all I need to do is multiply the site and species scores for the PC1 by -1, which would effectively flip the biplot. I am creating a blank plot using the plot command and accessing the results from a call to rda. I then use the calls to scores to obtain separate site and

Dear r-helpers! How can I integrate other distances (in the form of a dist object) into function metaMDS? The problem: metaMDS needs the original data.frame for the calculation and only the default distances of function vegdist are allowed. Any suggestions are greatly appreciated! Thank you, Kim -- Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3.5 - sicherer, schneller

Hi, I've been using R for a while now but I've got a problem with metaMDS (in the vegan package) that I can't quite figure out. I have a set of proportion data (from 0-1, rows sum to 1) that I apply metaMDS to using the command: nMDS.set=metaMDS(sqrt(test.set),distance="euclidean",k=3,zerodist="add",autotransform=FALSE) I am using a squared-chord distance

Hello R experts, I've used metaMDS to run NMDS on some fish abundance data, and am also working on correlating environmental data to the NMDS coordinates. I'm fairly new to metaMDS and NMDS in general, so I have what are probably some very basic questions. My fish abundance data consists of 66 sites for which up to 20 species of fish were identified and counted. I ran metaMDS on this data

Hello R-user community! I am running R 2.7.0 on a Power Book (Tiger). (I am still R and statistics beginner) Presently I try to run the function metaMDS (vegan) using an existing dissimilarity-matrix. As I would like to start with this matrix I thought I could just give the matrix using the x= -argument Test<-metaMDS(x=Dist.Gower) Fehler in inherits(comm, "dist") :

Hello all, I recently used the Vegan library quite extensively (in the context of text similarity assessment) on an Ubuntu 6.06 LTS system with R version 2.2.1 (2005-12-20 r36812). The Vegan lib is version 1.6-10. I hit on a problem yesterday, though, when trying to install R and Vegan on two further computers - one Windows XP and one further Ubuntu 6.06 machine, taking either R version 2.4.0

Hello, R-Help - I am trying to plot the results of an ordination from package vegan. The tricky part for me right now is getting the colors of the ellipses denoting the 95% confidence intervals of the group centroids to match the colors of the points for those same groups. >From and earlier post, I saw the code to make a plot of the ordination using different colors for my different groups.

The design decision in metaMDS says that it uses: Minchin, P.R. (1987) An evaluation of relative robustness of techniques for ecological ordinations. Vegetatio 71, 145-156. This is the paper that I found by the same name. Is this the correct reference? Minchin, Peter R.1987. An Evaluation of the Relative Robustness of Techniques for Ecological Ordination. Vegetatio. Vol. 69, No. 1/3: 89-107.

H ello R-experts, I want to do ordination plots using vegan metaMDS. I have a where many cells have zero values. Data structure: X[1:10,1:14] Height.1 Height.2 Height.3 Height.4 Height.5 Height.6 Height.7 Height.8 Height.9 Height.10 Height.11 Height.12 Height.13 D30I1A 46 0 0 0 0 0 0 0 0 0 39 0 98 D30I1B

I am using the function metaMDS with jaccard distances to ordinate a set of constituent by site matrix. I can post this data if it would be helpful, but it is large to include in an email. I can also provide reproducable code if necessary. I would like to get an R^2 value for the axes of the ordination configuration that I get with metaMDS in the vegan package is there a way to do this- is it

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

Hello, I read a lot about ordination, but I am still confused... I have data on species presence/absence for 8 different sites and I would like to represent my species and the sites on an ordination plot to see if some species are associated with specific sites. I used metaMDS function, which displays both sites and species and it seems to work well. However why are most people using CA instead of

Hello everyone! metaMDS(cm, distance = "euclidean", k = 2, trymax = 50, autotransform =TRUE, trace = 1, plot = T) (cm is a similarity matrix, in which values are positive integers or 0) I use this command to run NMDS on my matrix "cm". But the stress is very high after analysis. About 14. Actually, there is no improvment comparing with using isoMDS.

Hi, I'm trying to use metaMDS with a dissimilarity matrix of angles, not Bray-Curtis, and I wanted to know if there is an in-built function to produce a plot of stress values against dimensions, that could be used to determine the 'true' dimension of the solution. The number of objects is only a lowly 8 so any solution higher than 2-dimensional is not likely to be interpretable,

Dear r-Community, Step1: I would like to calculate a NMDS (package vegan, function metaMDS) with species data. Step2: Then I want to plot environmental variables over it, using function envfit. The Problem: One of these environmental variables is cos(EXPOSURE). But for flat releves there is no exposure. The value is missing and I can't call it 0 as 0 stands for east and west. Therefore I

am at my wit's end. I am not sure what is wrong with this data matrix. It is sparse because it is a matrix of species, but I have looked at the row totals and column totals and they are positive. rmetaMDS(x.d) Error in if (autotransform && xam > 50) { : missing value where TRUE/FALSE needed What is wrong? And in the future how in God's name do I easily diagnose whatever

I''m running a loop (illustrated below) that retrieves records from a table based on an id that might be different with each iteration. The loop uses the array scrns (composed of IDs) to find the related records in the Screens table. I''m attempting to store the returned results in an instance variable so I can use that data in a view. However, this code simply is overwriting