Journal of Statistical Physics, Vol. 88, Nos. 3/4, 1997. p. 637-664.
A novel class of multigrid algorithms for the variable-coupling isotropic Gaussian models is presented. In addition to the elimination of the critical slowing down (which otherwise might become much worse than usual in the case of strongly varying coupling values), the "volume factor" is also eliminated. That is, the need to produce many independent fine-grid configurations for averaging out their statistical deviations is removed, by applying multigrid cycles that sample mostly on coarse grids.