Fig. 9.

Assessment of the model optimality of the NLS approach. The results using ideal STAPLE and ideal NLS represent the estimates using the globally ideal performance level parameters with 5 atlases per estimate. NLS consistently converged to an estimate that is very close to “ideal” NLS (i.e., the global optimum). On the other hand, STAPLE consistently converged to a value significantly less than the global optimum. Additionally, the results of the “Ideal STAPLE” approach are only slightly better than a MV, which indicates the non-optimality of the traditional STAPLE observation model.