Hello,

I am running beta group significance to see what days are significantly different from other days, and I’m surprised by my results.

Based on the taxonomic bar plots of my samples from group 1 or group 2 (both over time as the x axis) if anything would be significant, I would expect it to be certain days in group 2 (for example day 1 and day 4). But when I run the analysis on each group separately, group 1 has days that show up as significantly different from one another, but not group 2. This is of course looking at the q values, after correcting for multiple comparisons.

Am I correct in that this is a surprising result, and suggests that something went wrong here? Am I making a critical error in how I am running my beta group significance command or is my understanding of this statistical test wrong?

Attached are the bar plots for the two different groups, as well as the results of the command. I tried other distance matrix’s as well, with the similar results.

Group1-weighted-unifrac-DayPhys-significance.qzv (397.1 KB)

Group2-weighted-unifrac-DayPhys-significance.qzv (445.6 KB)

qiime diversity beta-group-significance

–i-distance-matrix core-metrics-results-H+/weighted_unifrac_distance_matrix.qza

–m-metadata-file metadata2.tsv

–m-metadata-column DayPhys

–o-visualization core-metrics-results-H+/weighted-unifrac-DayPhys-significance.qzv

–p-pairwise

Any help would be appreciated,

thanks in advance for your time!

Masha