Left: cumulative density of the TS_max distribution for the on-time (red) and off-time regions (blue) including only sources with TS_max< 25. Dotted (dashed) lines show the Gaussian equivalent one-sided 3σ (2σ) probability of finding a larger TS than the TS indicated by the intersection of the dashed line with the blue distribution. The dash-dotted line shows the 2σ probability after correction for trials. Right: sum of TS values for 69 novae. The value of the on-time data is shown as a red line, while the off-time data are shown in blue. The shaded blue band reflects the uncertainty introduced by the limited statistics of the off-time sample.