Reproduction error of the speed ratio η. For a given exact η, after fitting the approximate formulations to the exact cratering distribution (assuming α_p = 1.75) and using the theoretical relations between asymmetry amplitude and speed ratio to reproduce the latter with the fits of the former, the reproduction error is calculated as the relative difference between the reproduced and the exact η. The reproduction errors that the spatial distributions of V, Θ, V_⊥, D, N, and N_c lead to (red, orange, yellow, green, cyan, and blue curves) are compared. Where v_enc = 10, 20, 30, and 40 km s^-1 on condition v_M = 1.0 km s^-1 are indicated (vertical dot lines).