Bias analysis for for an equatorial activity band (θ₀ = 85°, δ = 10°) with similar intensity to the Sun (ϵ_nl = 5 × 10⁻⁴) for T_obs = 2 years (top) and T_obs = 4 years (bottom). The colour and size of the circles indicate the modulus of the bias. The colour bar gives its scale normalised by the uncertainty, b(a_j)/σ. A white cross indicates an underestimation. A white dot is for an overestimation. Below 30° of inclination (grey area and symbols), the results are not reliable.