Histograms of measured ﹩t_{\sigma 10}/ t_{\mathrm{FWHM}\,}﹩. In all cases, ﹩t_{\mathrm{FWHM}\,}=3﹩ days, and the S/N is ﹩Q_{0}=42﹩. The five dashed vertical lines correspond, from left to right, to the true values when ﹩\delta =10﹩, 20, 50, 100, and ∞. The four points and error bars indicate the mean measured values and errors.