A simple and powerful way to deal with reciprocals of vanishingly small singular values recognizes that smaller singular values and the corresponding singular vectors, corresponding to sloppy parameter combinations, refer to the (effective) null space of the basis matrix. Sloppy, null space components make no discernable contribution to the quality of the fit. Their fitted magnitudes give no useful information about the relaxing system. SVD allows these components to be handled appropriately. The simplest way to handle them is to discard them. If one keeps only the first k numerically relevant columns of W and V , and keeps the upper left k -byk sub-matrix of Σ to create the truncated matrices ( )