interpretation beta diversity / permdisp / adonis

[colinbrislawn (Colin J Brislawn)]

Hello @AnkeWigger,

Great questions! I'm more of an numerical ecologist than a 'real' statisticien, but hopefully I can help.

@AnkeWigger

What is the difference between unweighted and weighted and what does this say about my data?

Here, the unifrac distance is being 'weighted' (or not!) by the abundance of the ASVs you are comparing between samples. Unweighted compares all differences in branch lengths equally, while weighted gives more weight to ASV based on their abundance in the data set.

@AnkeWigger

unweighted unifrac (p=0.043) and weighted unifrac (p=0.319)

This means that when you look at all ASVs there's a significant difference (p=0.043), but the most common ASVs that make up most of the community are not very different (p=0.319).

@AnkeWigger

I continued with the unweighted treatment data and also performed a permdisp on this data. This was not significant (p=0.349). From this, I conclude that the significant result in unweighted unifrac distances for treatment is not caused by a high dispersion.

It's not caused by a difference in dispersion. But yeah.

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@AnkeWigger

I am a bit lost in the statistical maze of all kinds of different analysis methods
What have I exactly calculated and what do these results mean?

Check out these posts! (probably easier to read then a stats paper, and with more emoji )

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And of course, let us know if you have any questions!