Law of Frequency of Error


In the earliest laboratory notebooks, the wall-mounted m­echanism shown in this image was simply called “the pinball machine.” In the published output of the research program of which it was a part, it wen­t by the more dignified­ appellation Random Mechanical Cascade, yielding a catchy acronym: RMC. Around the lab, however, the ­device was known affectionately as ­Murphy, since if anything could go wrong, it would. In a way, of course, this was exactly the point: the whole system—the nine thousand polystyrene balls droppin­­g through a pegboard of 330 precisely cantilevered nylon pins, the real-time photoelectric counters tallying (by LED readout) the segmented heaps forming belo­w, the perennially balky bucket-conveyor for resetting an experimental run—had all been painstakingly constructed and ca­librated in order first to exemplify, and then to defy, what the Victorian statistician ­Francis Galton dubbed the “Law of Frequency of Error.”­

more from D. Graham Burnett at Cabinet here.