Average bias on 10⁶ MC noise realizations for the conventional estimator for different true values as a function of S/N: in the canonical case of the noise covariance matrix configuration (ε_eff = 1) − colored plain curves and in the extreme regime (ε_eff up to 2). The colored curves are shown from top to bottom in the same order as the legend lines on the right part of the figure. The low regime regions are invisible at the current plot scale and coincides with colored curves. The dashed line represents the “zero bias” level.