Figure 2

Permutation test procedure with simulations. (a) The identified region with p < 0.05, through a voxel-by-voxel based t-test (gray contour) and the permutation test (black contour). (b) The average dose difference map${\tilde{d}}_k$ (k = 1,…,128×128) for the observed sample. (c) The SD σ _k of the dose difference, computed from 1000 permutated random samples. (d) The normalized dose difference map${\tilde{T}}_k$ for the observed sample, which is (b) divided by (c). (e) The distribution of T_max,i from i = 1,…,1000 permutation samples, where${\tilde{T}}_{\text{max}}$ is the maximum value in figure (d) and T^∗ is the 95 percentile of T_max,i.