Power functions and their use in selecting distance functions for document degradation model validation

Two document degradation models that model the perturbations introduced during the document printing and scanning process were proposed recently. Although degradation models are very useful, it is very important that we validate these models by comparing the synthetically generated images against real images. In recent past, two different validation procedures have also been proposed to validate such document degradation models. These validation procedures are functions of sample size and various distance functions. In this paper we outline a statistical methodology to compare the various validation schemes that result by using different distance functions. This methodology is general enough to compare any two validation schemes.