I have exported the weighted unifrac PCoA data to a file called “ordination.txt.” However, I am not sure if I understand this file correctly.
Can anyone please explain what the numbers for each section corresponding to?
“Eigvals”
Proportion explained
Are the numbers for each samples corresponding to their location of PC1, PC2, PC3…etc (from left to right)?
If I would like to know the PCA value by obesity status or by gender, will I be able to use these values and incorporate with the demographic information?
Funny enough I just came across this thread expounding upon PCA. I’m guessing a bit of Googl’ing will lead you down many roads; for an exhaustive list of references, you might start here; the same site has quite a bit of background info on ordination too see here.
Am I the only one who finds tremendous joy when stumbling across websites that remind me of my time browsing with NetScape Navigator circa 1993?
Thanks for the info. I will read through them to get a better idea of the PCA analysis.
Can I ask you a quick question before that? I would like to confirm that columns next to the first column which lists all the sample ID are the values from the axes1 (2nd column), then axes2 (3rd column) and axes3 (4th column)…etc.