Granularity required for accurate computation with From Score to P-value. This figure compares the theoretical necessary granularity and the granularity reached by FROM SCORE TO P-VALUE. For example, granularity 10-2 is necessary for 17 matrices. It means that the round matrix with granularity 10-1 gives a wrong P-value, whereas the round matrix with granularity 10-2 gives an accurate P-value. Amongst these 17 matrices, FROM SCORE TO P-VALUE stops at 10-2 for 11 matrices, performs one supplementary step at 10-3 for 5 matrices, and two supplementary steps, at 10-3 and 10-4, for one matrix.