Complementary cumulative distribution of the H_tr values obtained by performing an H test on W2 data at 100,000 independent trial periods (see the main text for details). The solid black and grey lines indicate the best-fit function of the observed distribution, p(H_tr > H) = exp( − B ⋅ H) for B = 0.3, and the relation expected if the noise is uncorrelated (B = 0.4; de Jager & Büsching 2010), respectively. The horizontal dashed line marks the false alarm probability of the H^* = 18.1 value observed in SiFAP2 W2 data.