WY-test statistics.

Test statistics from WY-tests with 15% trimming for the silica concentration, microwear (primary surface only) and texture analyses of the primary surface (A), S-F surface (B), and S-L surface (C).Values in bold indicate a significant difference (p≤0.05). Ft = test statistics, nu1 and nu2 = 1st and 2nd degree of freedom, p = significance level, SC = silica concentration [%] in animal feeds, Np = number of pits, Ls = length of scratches (µm), Sda = closed dale area [µm2], Sdv = closed dale volume [µm3], S5v = five point pit height [µm], Sal = auto correlation length [µm], Sp = maximum peak height [µm], Ssk = skewness, Sv = maximum pit height [µm], Sz = maximum height [µm].