Fig. 2.

Global statistics and parameters for the iterative optimisation of the OMP global models MII (sphere), MIII (prolate spheroid), MIV (oblate spheroid), and MV (ellipsoid) using the new model-free optimisation protocol. Each glyph in the plots corresponds to one iteration of the new protocol and consists of the optimisation of the model-free parameters of models m0 to m9, model elimination, AIC model selection, and finally the optimisation of the diffusion tensor simultaneously with all model-free parameters. Hence each point prior to convergence corresponds to the optimal parameters located at the global minimum of a different space . In the plot of the parameter, absolute values have been presented. Hence for the oblate tensor the values are the negative of those shown. For the optimisation of the diffusion tensor the orientation of the backbone NH bond vectors were taken from the X-ray crystallographic structure 1F35