Fig. 4.

With high precision MEG data, model evidence decreases with dipole orientation error.

a Each line shows the change in model evidence (ΔF) as the orientation of the dipole used for inversion is rotated away from the true orientation at different SNR levels (co-registration error ​= ​0 ​mm). The shaded regions represent the standard error of ΔF over all 100 simulations at each angular error value tested. The lower dotted line (at ΔF ​= ​−3) show the point at which the imperfect model is 20 times less likely than the true model. The differences between models become more apparent at higher SNR. b As in a, for different magnitudes of co-registration error (SNR ​= ​0 ​dB). Co-registration error has a smaller impact than SNR on discriminating between models with different dipole orientations.