Cumulative number of individual galaxies for which the absolute value of the difference between observed and computed oxygen abundance at the optical edge of the galaxies’ R₂₅ isophotal radius is less than a given value. The cumulative number is normalized to the total number of galaxies. The computed oxygen abundances are obtained from the one-dimensional relation O/H = ﹩f({{{\rm \Sigma}}_{{{L}_{W1}}}})﹩ (Equation (12)) (dotted line), from the two-dimensional relation O/H = ﹩f({{{\rm \Sigma}}_{{{L}_{W1}}}},{{h}_{W1}})﹩ (Equation (13)) (solid line), from the two-dimensional relation O/H = ﹩f({{{\rm \Sigma}}_{{{L}_{W1}}}},{{f}_{B}})﹩ (Equation (14)) (long-dashed line), and from the two-dimensional relation O/H = ﹩f({{{\rm \Sigma}}_{{{L}_{W1}}}},T)﹩ (Equation (15)) (short-dashed line).