Scatter plot of predicted RMs versus observed RMs in the best-fit parameter configuration, using a model with B₀₁ left as free parameter and setting C_n = 1. Results are displayed for the two cases of non-uniform weights, after the two analyses described in step 1 (yellow squares) and step 2 (green circles), respectively. The dashed 1:1 line shows the diagonal, corresponding to the ideal situation where predicted and measured values are equal. The solid (red and brown) error bars denote the σ_RM,i uncertainties for each measurement due to radiometer noise as quoted in Mancuso & Spangler (2000), whereas the dashed (blue) errorbars denote the σ_RM,i^∗ total uncertainties obtained after adding the contribution of RM fluctuations, estimated to be δRM  = 1 rad m^-2 for the sake of this analysis.