Immaturity of Chance
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Immatuiity ofChance Most of us trained in science or engineering hâve been exposed to a course or two in probability and statistics. At least we probably hâve. Perhaps at the rime, the concepts were not enrirely intuitive. That the standard déviation in a total number of occurrences of events occurring randomly in time is the square root of that number may hâve been obvious to Poisson, but not necessarily to the rest of us. Yet, for example, that the chances of both of two probability-1/2 events happening is one out of four seems somehow natural enough. I suspect that comfort with such concepts cornes more from faith ingrained in class than from expérience. The Law of Large Numbers, in fact, often prevents us mère mortals from living long enough to test an event's true likelihood. Probably because I am among the faithful, I am continuaUy perplexed by the apparent predictability of supposedly random or accidentai events. (Many accidents can occur randomly but ail random events, e.g., earthquakes, need not arise accidentally.) Of ail the laws I remember from that statistics course, Murphy's was not among them. Murphy's version of the coin-flipping experiment is the rule that, "more often than not, a dropped slice of bread will land buttered side down." Although it is tempting to work out the torque arising from différenciai drag between bare bread and my favorite spread, I rarely drop food from so high a height that it would matter. Anecdotal évidence, however, clearly favors Murphy over physics. Another phenomenon many travelers encounter is the affinity shown by hooks on those elastic "bungee" cords for any and ail objects to which you don't want them to attach. Unless you handle thèse récalcitrant ropes in an excruciatingly measured and methodical manner, always keeping a grip on the free ends, they will invariably latch on to something, despite being surrounded by cavernous régions of free space where they could dangle harmlessly. Any number of other supposedly random types of events which seem to rise above their natural probabilities could also be cited. The call for which you've waited hours cornes just when you step
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