Hi qiime2 community, I have a volcano plot interpretation question resulting from my ANCOM analysis
Having ran ANCOM at the genus (level 6) and species level (7) comparing a control group to a lesion group . and it gave me interesting results: Treponema species has a high W – so they are standout taxa that qiime pointed out.
These really high W-statistic numbers have negative clr – and I am unsure why that is. Does it actually mean it is decreasing in abundance across the categories? I was under the impression that usually taxa on the upper right are the ones that are differentially abundant where taxa increased abundance.
And included in the output is the abundance table – and it is pretty clear that these species are clearly more abundant in the lesions than in the control samples. So WHY are these taxa despite the high W’s have a NEGATIVE clr.
I have also other examples at different taxonomic levels and found taxa (genus, family, etc) have high Ws and positive clr’s.
How do I properly interpret this – Should I basically disregard whether it’s on the left or the right side of the graph (+/- clr) because the W number is so high?
Thanks a bunch, and appreciate any feedback and for reading this,