I have a question about metadata categorical column. But the categories is :0,1,2,3, in the Zahnverlust-durch-Zahnlockerung-unter-Verwandten (teeth loss) column when do Alpha diversity plot, category 0 does not show up. Could someone please explain this? also about continued variable, what method should be used in Alpha diversity analysis? Thank you in advance.
0 samples been rarefied out of your table?