...process
See next section.

...algorithm
It is interesting to note the origin of the appellation of this statistical method. It is of course taken from Greek mythology. Procrustes is the villainous son of Poseidon who forced travelers to fit into his bed by stretching their bodies or cutting off their legs. He was killed by Theseus who delivered to him the same punishment he had meted out to his victims.

...large
The resulting errors are obviously more tedious to quantify in terms of physical units (i.e. mm) if the pixel calibration errors are large, requiring inclusion in quadrature [Bev69], but the errors in the determination of voxel dimensions are usually negligible in practice and are so treated for simplicity.

...A
The correct registration transformations are actually known from the generation of the random transformations to simulate the uncorrelated orientation which requires registration. This method of storing the correct registration transformation was chosen for ease of coding the simulation and greater conceptual similarity to the study based on real scans.

...Simplex
From an implementation of the Nelder-Meade algorithm from Matlab.

lukban@pet.mni.mcgill.ca
Wed Jan 18 14:28:16 EST 1995