Rank transformation and threshold calculation. Rank transformations constitute an efficient strategy to perform robust analyses with respect to distributional assumptions.22 (A) Posterior probability densities for MPN,U-ET and MPN,U-MPF patients fitted to the measurements after rank transformation. A rank transformation of the data was applied to perform the classification analysis. The posterior probability densities are plotted for both MPN,U-ET and MPN,U-PMF patients. The threshold of 10.48 for the ranks is obtained by determining the rank with equal posterior probabilities. (B) Transformation. The threshold value for the ranks (10.48) was translated to the measurement scale. Ranks are plotted in a vertical direction; the horizontal axis denotes the measurements as percent of nuclear-positive cells. The threshold 10.48 for ranks (vertical axis) corresponds to 20.26% nuclear-positive cells (horizontal axis).
