A phyloseq object containing merged information of abundance,
taxonomic assignment, sample data including the measured variables and categorical information
of the samples, and / or phylogenetic tree if available.
group
group. A character string specifying the name of a categorical variable containing grouping information.
pvalue
pvalue threshold for significant results from kruskal.test
normalize
to normalize the data before analysis(TRUE/FALSE)
method
A list of character strings specifying method to be used to normalize the phyloseq object
Available methods are: "relative","TMM","vst","log2".