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You’re in a world the place precisely 90% of all folks dwell for precisely 3 years, and precisely 10% of all folks dwell for precisely 100 years. Apart from what I point out right here there isn’t any info that may point out whether or not you might be somebody who may have lived for 3 years by the top of your life or whether or not you might be somebody who may have lived for 100 years. Regardless of how lengthy you’ve got been alive, or whether or not you’ll die after having lived for precisely 3 years or precisely 100 years, your reminiscence lasts for precisely 1 hour, and something that occurred greater than 1 hour in the past you could have completely no reminiscence of. Whether or not you might be somebody with a lifetime of precisely 3 years or somebody with a lifetime of precisely 100 years a second is the smallest unit of time you’ll be able to expertise and a second looks like the identical size of time both means. From while you pop into existence till you die you feel and look precisely the identical, and there’s no method to know your age. You additionally look the identical whether or not you might be somebody who will die after having lived for precisely 3 years or somebody who will die after having lived for precisely 100 years. You’re additionally aware for each second of your life and each second of your life feels the identical. Principally nothing apart from the statistics I gave earlier can provide you a clue as as to whether you might be somebody who may have lived for precisely 3 years or precisely 100 years when you die.
From your individual perspective what’s the likelihood that when you die you should have lived for precisely 100 years?
requested yesterday
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In a inhabitants of 10 random folks, 1 can be long-lived, accumulating 100 person-years, and 9 can be short-lived, accumulating 27 person-years. So 100/127 person-years are lived by long-lived folks. So underneath the sturdy self-sampling assumption, the likelihood is 100/127, or ~79%.
That assumption is
philosophically controversial, however I feel you most likely agree with it.
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Let’s name B is the yearly start fee.
The overall inhabitants is on common B*90%*3 + B*10%*100 folks.
The quick lived inhabitants is on common B*90%*3.
So if you happen to decide any individual alive, the likelihood for it to be short-lived is
27 / 127 = ~21%.
However
However on the opposite facet, as a citizen of the world, you might be born with 90% likelihood to be short-lived.
So…
Which one is appropriate?
I feel that the truth that you might be alive is a measurement of your life span. Alive means most likely long-lived, as a long-lived individual has extra alternatives to ask the query of its life-span.
So you could have an a priori likelihood of 90% to be short-lived. However the truth that you might be alive and you don’t have any concept how previous you might be tilts the steadiness in the direction of being long-lived. And the calculations offers solely 21% for being short-lived.
So it offers a 79% probabilities to dwell 100 years.
answered 20 hours in the past
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The frequentist reply to this query is
Both 0 or 1, however you do not know which
It is because
You have not specified the way in which that the person is sampled, so there is no randomness in the issue as it’s at the moment said.
This isn’t simply pedantry – the sampling mechanism is significant to the issue’s decision and totally different sampling procedures will result in fully totally different options.
Two cautious descriptions of sampling procedures could be:
(1) You begin as a disconnected consciousness that’s positioned in a child being born that’s chosen uniformly at random from all infants born that day. You’re requested the query after your loss of life. On this case, there isn’t any lifetime bias, and the likelihood that you simply lived for 100 years 10%.
(2) You’re enrolled within the examine on a selected day. When you die, the investigator asks you the query. On this case, the truth that you have been enrolled within the examine on a selected day is informative, since short-lived individuals are much less prone to be round to be enrolled. Due to this fact, on this case, the lifetime bias is related and the likelihood is 79% as mentioned in earlier solutions.
answered 2 hours in the past
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