Results from the fitting different noise realisations of the Fig. 11 observations. Frame a shows a few examples of the observations (black crosses) and individual fits (solid curves). Frame b–d show the distributions of τ estimates (100 noise realisations) for the 1-MBB, 2-MBB, and 3-MBB models, respectively. Each frame quotes the mean value and the standard deviation for the estimates relative to the true value, τ/τ₀.