All Questions
Tagged with ecology multidimensional-scaling
10 questions
0
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1
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44
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test for significant differences in communtiy composition between habitats? required PERMANOVA sample size?
I sampled spiders in 5 different forest-stands. I originally had a sample size of 32 per forest-type, but as I had to pool the data I now just have 8 samples per forest type.
I did an ordination with ...
- 69
0
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0
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40
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NMDS with Morisita-Horn Index: which data-transformation makes sense?
I have a community matrix of spiders, which I captured during winter in different forest stand-types.
I now want to perform an NMDs. For that I want to use the Morisita-Horn Index from R in the ...
- 69
1
vote
1
answer
360
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Best solution was not repeated - no reliable result for metaMDS?
I have abundance data of spiders that I captured in different forest stands and I want to perform an NMDS. It generally works, although the stress value is relatively high. However, I get the message ...
- 69
1
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1
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246
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Transforming count data for NMDS?
I am looking at species count data. Due to large counts of certain species, I initially fourth root transformed the data. I am using Bray-Curtis distance measurement.
However when using vegan::metaMDS,...
- 63
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9
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Should data be transformed for NMDS? [duplicate]
I am looking at species count data. Due to large counts of certain species, I initially fourth root transformed the data. However when using vegan::metaMDS-Bray Curtis distance, the stress value for ...
- 63
1
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1
answer
2k
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How to deal with stress over 0.2 in NMDS in large dataset [closed]
I am analysing a large dataset (2000 rows by 250 columns) of the presence of species in several locations over the last 20 years. I have conducted a NMDS in order to identify differences between the ...
2
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1
answer
3k
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How to analyse community composition in relation to environmental variables with nMDS?
I have a big data set (over 1000 observations) with abundances of over 60 species at 15 different sites over two years. Each site was divided into 30 sampling points and these were each sampled four ...
- 33
2
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2
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353
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Book about ordination in ecology
I am looking for a book that would cover a lot of different ordinations techniques (indirect gradient analysis e.g. PCA, CA, DCA, MDS, nMDS but also direct gradient analysis e.g. CCA, CCorA, RDA) with ...
2
votes
1
answer
325
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Method named 'BEST' in multivariate analysis - what is it?
I've read a few ecological papers where a 'BEST' procedure is used to assess effect of environmental parameters on biological community composition, after multivariate analysis like MDS. For instance ...
- 459
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0
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1k
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Representing experimental data by unconstrained ordination: PCA, PCoA, or NMDS?
I have a dataset composed by presence of different bacterial families in function at different pesticide treatment. I need to find a good representation of my data but I don't know which method (...
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