Metamorphic testing of a Monte Carlo modeling program

Abstract

Photon propagation in biological tissue can be equivalently modeled with Monte Carlo simulations numerically or by the Radiative Transfer Equation (RTE) analytically. However, testing of a Monte Carlo program modeling photon propagation in biological tissue is difficult due to the unknown character of the test oracles. Although approaches based on Beer-Lambert law, van de Hulst's table or RTE can be used for testing the Monte Carlo modeling program, these approaches are only applied to the program that is designed for homogeneous media. A rigorous way for testing the Monte Carlo modeling program for heterogeneous media is needed. In this paper, we investigate the effectiveness of the metamorphic testing approach to test a Monte Carlo modeling program for heterogeneous media. In addition, the metamorphic testing is extended with the evaluation of the adequacy of testing coverage criteria to measure the quality of the metamorphic testing, to guide the creation of metamorphic relations, to generate testing inputs, and to investigate the found exceptions. The effectiveness of the approach has been demonstrated through testing a Monte Carlo modeling program we developed for simulating photon propagation in human skins.