Fig. 7. Plots of (a) (0) vs. D₀ and (b) widths of -intervals: (0) - (q_i,+) vs. (q_i,-) - (0) for soils in the three groups considered. The numerical values of q_i,+ and q_i,- were the same and equal to the smallest of the two values defining a q interval (see Table 3). Proximity to the 1:1 line implies (a) more homogeneous distributions, or (b) more symmetric f()-spectra. In plot (b) two soils of Group 2 had identical values and show as one point in the graph.