Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12859-019-2783-8/MediaObjects/12859_2019_2783_Fig2_HTML.png)
ROC curves for group comparison tests. In SIM1, seven parametric methods and six rank-based methods are compared. (a): normal with small correlation; (b) normal with large correlation; (c): double exponential with small correlation; (d) double exponential with large correlation. AUC values are reported in the legend. Plot A is zoomed to facilitate the view of curves that overlay on top of each other. When curves are severely overlaid, line widths are slightly adjusted to improve readability. For both ρ=0.2 and ρ=0.8, the PB-transformed parametric and rank-based tests outperform all other tests