Survival times of the isolated non-resonant systems (T_{s, isolated}) versus the survival times of the perturbed non-resonant systems (T_{s, perturbed}) for HR 8799. The systems are biased towards surviving longer when perturbed. The colour of a data point indicates if a system survived longer when isolated (blue, i.e. left of y = x) or survived longer when perturbed (orange, i.e. right of y = x). The background shows a kernel density estimation.