Fig. 6

Result comparisons when linking microbiome compositions with location (A1–A4) and gender (B1–B4). A1 and B1 plot the U-Curve of number of significant hits. In A2 and B2, we rank the significance of the 267 features, and then plot their \(-\,\log _{10} p\)-values with the same order across permutation scenarios. A3 and B3 plot the U-Curve of proportion of significant hits. A4 and B4 plots the fragility index of the top 50 features with a decreasing order. To save space, the legend listing the names of the 50 features are omitted