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There are ~9000 Adventists in Loma Linda. This is two categories you can split people into, then intersect. There are 330,000,000 million Americans. There are likely millions of categories people can be split into. Just for fun let's say counties (6000+) then any of a zillion other cross items (left handed, blue eyed, above average height, smells like butter, etc., etc.,Etc.) Say we find 10,000 of these categories. Life expectancy is decently modeled as a gaussian with std deviation 8 years. A 10 year excess is a z-score of 1.25, and 10% of samples will be at this point. The odds of TONS of subsets of size 9000 of the 330,000,000 people that can be found in the same pair of county+trait from the 600,000,000 pairs is nearly 1. Thus the Adventists in Loma Linda are far more likely to be one of these many blips that have zero causal power than they are to have special life sauce. Finding them is merely an artifact of being able to filter data, not a special power of the objects. Or a simpler way: pick two binary traits, split the 330m Americans into 33,000 chunks of size 10,000 where each group has all in one of the four pairs of traits, and you would expect (more or less - there is some more math to do here) that 10% of these groups has average lifespans over 10 years, i.e., 3,300 of the groups are the same as the Loma Linda Adventists. No magic needed. Just rolling dice. |