Comparison of M_BH estimates between incident and simulated data derived from the Hα (see Sect. 7.3 for details). Left panel: M_BH derived from the best fit of the incident data that considers only the broad component of the Hα emission line profile (see Sect. 6.1). Right panel: M_BH derived from the best fit of the incident data that considers one single Gaussian component of the Hα emission line profile (see Sect. 7.1). Symbols are as in Fig. 11.