4 ms·
> If "longevity" were a bell curve, we would see some humans at the 150 years old mark. We do not. I agree with everything else (including that its not a bell
by setr 5y ago
> If "longevity" were a bell curve, we would see some humans at the 150 years old mark. We do not.
I agree with everything else (including that its not a bell curve), but this particular reasoning seems off — it could still follow a bell curve even if we never see the rarer items… because we’re only talking about approximating a bell curve. Just as height’s bell curve suggests a 30ft human could eventually occur, but we’d never actually expect it to actually happen in reality (because confounding factors will start to trigger) - but we still say height follows a bell curve.
- bsder 5y agoNo, the bell curve for height does not suggest a 30ft human would ever occur. That would be somewhere around 90+ standard deviations out--that's so wildly improbable as to be effectively 0. A "mere" 7 standard deviations is effectively 1 in a billion. And that's somewhere around a 7 1/2 foot tall human (who we do see occasionally). "Standard deviation of lifespan" (a somewhat erroneous idea since we're not actually on a bell curve) is somewhere around 10 years. 150 years old is 7 standard deviations--improbable but not impossible. If we're following a bell curve, 1 in a billion people should be 140 years+ and 1 in 10,000 should be 120 years+. The fact that we don't see these probabilities is extremely strong evidence we're not on a bell curve. And not being on a bell curve immediately throws out huge chunks of statistical "rules".