> It's not just random noise. A small population is more impacted by individual events so far there is often reasons for such aberrations. 

That is random noise. A small population is impacted far more by noise.



I would not call a nearby chemical dump 'random noise'.

Consider the dean of a tiny school wants to be different where the dean of a large school wants to be better at a wide range of things. The first dean will have a larger impact on a smaller number of things. Further, the dean of the smaller schools choice of focus is going to have a major impact.