I have an error on Differential abundance testing with ANCOM part.
In the tutorial written:
ANCOM assumes that few (less than about 25%) of the features are changing between groups. If you expect that more features are changing between your groups, you should not use ANCOM as it will be more error-prone (an increase in both Type I and Type II errors is possible).
While in my samples different ASVs. Absolutely it is not unique. Now I would like to know why it said ’ there are no ‘within’ variance because each group of samples contains only a single sample’?