Statistical relative | Bias_ψ | (left-hand panel) and Risk_ψ (right-hand panel) averaged over ψ₀ between − π/ 2 and π/ 2, as a function of the S/N on p₀/σ_p,G, for the four estimators: naïve (black), ML / MAP (blue), MP2 (green), and MB (pink). We consider two set-ups of the covariance matrix here: ε_eff = 2 (solid line) and and ε_eff = 1.1 (dotted line). 1000 Monte Carlo realizations are performed for each S/N, and for each one of the 100 values of the polarization angle used in the average.