Margin and 2D histograms of time lags and associated maximum correlation values for couple 193 –171. Subfigure (a) in red shows the original distribution for the event pixels. Subfigure (b) shows the background subtracted event pixels. The blue contours in the central panel of subfigure (a) are the 20, 40, 60, and 80 percentiles of the QS pixel distribution. The green colors in the main panels are the confidence levels, and the distributions of the light curves used to compute them are plotted with the same color in the margin histograms. The margin histograms were normalized by their total number of pixels. The parameter ν_{> 95} is defined as in Fig. 5.