Normalised distribution of the number of chance coincidences between GRBs and FRBs obtained by cross-matching the 10⁵ realisations of GRB and FRB samples when only spatial and temporal constraints (cyan) were applied and when the distance constraint (blue) was also taken into account. The vertical solid lines mark the 3σ confidence interval, and the vertical arrow marks the number of matches using real samples when only spatial and temporal constraints were considered.