Fig. 2

Median area under the receiver operating characteristic curves. This was obtained by LOOCV of a 5-nearest-neighbor classifier across 200 random selections of 50% of the arrays, using the HAGS probe sets (green dots) and 500 random selections of 150 probe sets (box plots), over the two AD cohorts. AD Alzheimer’s disease, AUC area under the receiver operating characteristic curve, HAGS healthy ageing gene signature, LOOCV leave-one-out cross validation