Top panel: Comparison of the dispersion in the Hyades sample (thick line) and the average of the mock data sets with mean pollution of 1.0 M_⊕ (thin line); 90% confidence bands are drawn for the dispersion in the data (dotted lines) and the mock data sets (dashed lines). Bottom panel: Same as the top panel but for the 0.5 M_⊕ case.