5 ms·

“It sounds dramatic to say that they don’t age at all, but basically their likelihood of dying does not change with age once they’re past reproduction,”

JoeAltmaier 4y ago
Same with humans, to a degree. Actuarials place your chance of dying at 50% after the age of 80. So we 'stop aging' after 80!
- spython 4y ago
  71569457046263802294811533723186532165584657342365752577109445058227039255480148842668944867280814080000000000000000000 is a good age to stop aging. Sorry, couldn't miss a factorial joke.
  - RGamma 4y ago
    You could witness https://czep.net/weblog/52cards.html https://czep.net/weblog/52cards.html 3748508088259971967302999598973478215811072000000 times until then. Frankly, I'm terrified.
- vaishnavsm 4y ago
  Correct me if I'm wrong, but shouldn't the criterion be that the probability of death is the same between 80-90, 90-100, and so on (for example) to say that humans stop aging after 80? Saying that your chance of dying is 50% after 80 != saying it's the same consistently after 80?
  - zamfi 4y ago
    I think the parent poster meant "annual chance of dying after 80" as in, for any year 80+, you have a 50% chance of dying that year: it doesn't go up each year, so you don't "age" in that sense.
    - jewayne 4y ago
      But this is not true. The life expectancy for an 80 year-old Caucasian American woman is over 9 years. The life expectancy a 90 year-old Caucasian American woman is less than 5 years.
      - peregren 4y ago
        Yes the coin of death remembers how lucky you were in your eighties and skews towards tails in your 90s. Still 50/50 as its a coin.
        cylon13 4y ago
        There’s only two possibilities: I’ll either win the lottery or I won’t, so it’s a 50/50 shot!
        mejutoco 4y ago
        I guess I am a bayesian :)
- izzydata 4y ago
  But if you flip a coin every year the chances of getting heads after 10 rolls is quite high.
  - hutzlibu 4y ago
    Yup, it is then still quite high - exactly 50%.
    - capitainenemo 4y ago
      I'm sure he meant within 10 years. So (1-(0.5¹⁰))=99.9% chance (that is, chance of flipping tails 10 times in a row is 0.5¹⁰ - chance of any head is what's left)
- pawelmurias 4y ago
  Wasn't this result largely cause by small sample size?
- deleted 4y ago
  [deleted]
- andsoitis 4y ago
  Does this actuarial table support your claim that chance of dying is stable at 50% after 80: https://www.ssa.gov/oact/STATS/table4c6.html https://www.ssa.gov/oact/STATS/table4c6.html
  - jewayne 4y ago
    I love how, even for men, life expectancy doesn't fall below one year until age 113.
    - candiodari 4y ago
      Well that happens because the ones who die get excluded from the calculation. So it doesn't drop off nearly as fast. It's calculating P(death|age = N), not P(death|age <= N). Now luckily you can calculate the second one, by adding all values up to that age together. I would argue the value you're looking for, "when you die", is different still: P(death|age <= N, current_age=M), where M is your current age. You know, taking into account that you didn't die from sudden infant death syndrome or measles, or you wouldn't be here, but leaving everything in the future up to chance. To get that value, you should the odds of dying at all ages up to N, but only starting at your current age.
  - LeifCarrotson 4y ago
    No, not exactly. Your chance of dying at year 80, per that table, is about 5% at 80, 15% at 90, and 30% at 100 (averaging for males and females). Not the same, and not 50. I think the observation they're trying to convey is that your expected number of years remaining goes down by much less than one year per year at those ages. A 90-year-old can expect to live for another 4.5 years, but on their 91st birthday, the chart surprisingly predicts not 3.5 but 4.2 years remaining. The number of expected years left drops more than 0.95 years per year until age 20, 0.9 years per year until age 40, down to 0.8 at 60, 0.5 at 80, and 0.1 at 100.
    - bena 4y ago
      Quirks of statistics. To have an average of 4.5, you need people to die before and after the mark. So a lot of people drop off between 91 and 92. But those who make it to 92 have about 4.2 years remaining. If you have a population of 100 people and 50 of them will live less than 1 year, and 50 of them will live an average of 10 years, that's 5.5 years on average for the whole population. But if you check that same population one year later, you will have 50 people who all live 9 years on average. You've managed to increase the average by eliminating the bottom. Same thing is happening here. And it's probably similar to professional sports careers. The average NFL career is about 3 years. However, if you make to 3 years, your average career length is about 7 years. We probably need more of a median or mode than a mean.
- ddulaney 4y ago
  This is not true. Either that it’s 50% at 80 or that it is flat after 80. Here’s an actuarial table: https://www.ssa.gov/oact/STATS/table4c6.html https://www.ssa.gov/oact/STATS/table4c6.html Annual chance of dying is 5% at 80 and continues rising every year (9% by 85, 16% by 90, 25% by 95, 35% by 100).
  - JoeAltmaier 4y ago
    I see that! The chart I recall is clearly very out of date. Thanks!
- Someone 4y ago
  https://en.wikipedia.org/wiki/Gompertz–Makeham_law_of_mortality https://en.wikipedia.org/wiki/Gompertz–Makeham_law_of_mortal...: “The Gompertz–Makeham law states that the human death rate is the sum of an age-dependent component (the Gompertz function, named after Benjamin Gompertz), which increases exponentially with age and an age-independent component (the Makeham term, named after William Makeham). In a protected environment where external causes of death are rare (laboratory conditions, low mortality countries, etc.), the age-independent mortality component is often negligible. In this case the formula simplifies to a Gompertz law of mortality. In 1825, Benjamin Gompertz proposed an exponential increase in death rates with age. The Gompertz–Makeham law of mortality describes the age dynamics of human mortality rather accurately in the age window from about 30 to 80 years of age. You probably remembered the first part of the sentence following that: “At more advanced ages, some studies have found that death rates increase more slowly – a phenomenon known as the late-life mortality deceleration – but more recent studies disagree.” Even if that were true (something wikipedia contests. See also https://en.wikipedia.org/wiki/Late-life_mortality_deceleration https://en.wikipedia.org/wiki/Late-life_mortality_decelerati...), that doesn’t mean rate of death decreases, just that it increases slower than this model predicts.
- sethammons 4y ago
  to the downvoters: https://www.science.org/content/article/once-you-hit-age-aging-appears-stop https://www.science.org/content/article/once-you-hit-age-agi... At a certain point, humans appear to stop aging. Just it is at 105, not 80 :)

JoeAltmaier 4y ago

Same with humans, to a degree. Actuarials place your chance of dying at 50% after the age of 80. So we 'stop aging' after 80!

spython 4y ago
71569457046263802294811533723186532165584657342365752577109445058227039255480148842668944867280814080000000000000000000 is a good age to stop aging. Sorry, couldn't miss a factorial joke.
- RGamma 4y ago
  You could witness https://czep.net/weblog/52cards.html https://czep.net/weblog/52cards.html 3748508088259971967302999598973478215811072000000 times until then. Frankly, I'm terrified.
vaishnavsm 4y ago
Correct me if I'm wrong, but shouldn't the criterion be that the probability of death is the same between 80-90, 90-100, and so on (for example) to say that humans stop aging after 80? Saying that your chance of dying is 50% after 80 != saying it's the same consistently after 80?
- zamfi 4y ago
  I think the parent poster meant "annual chance of dying after 80" as in, for any year 80+, you have a 50% chance of dying that year: it doesn't go up each year, so you don't "age" in that sense.
  - jewayne 4y ago
    But this is not true. The life expectancy for an 80 year-old Caucasian American woman is over 9 years. The life expectancy a 90 year-old Caucasian American woman is less than 5 years.
    - peregren 4y ago
      Yes the coin of death remembers how lucky you were in your eighties and skews towards tails in your 90s. Still 50/50 as its a coin.
      - cylon13 4y ago
        There’s only two possibilities: I’ll either win the lottery or I won’t, so it’s a 50/50 shot!
      - mejutoco 4y ago
        I guess I am a bayesian :)
izzydata 4y ago
But if you flip a coin every year the chances of getting heads after 10 rolls is quite high.
- hutzlibu 4y ago
  Yup, it is then still quite high - exactly 50%.
  - capitainenemo 4y ago
    I'm sure he meant within 10 years. So (1-(0.5¹⁰))=99.9% chance (that is, chance of flipping tails 10 times in a row is 0.5¹⁰ - chance of any head is what's left)
pawelmurias 4y ago
Wasn't this result largely cause by small sample size?
deleted 4y ago
[deleted]
andsoitis 4y ago
Does this actuarial table support your claim that chance of dying is stable at 50% after 80: https://www.ssa.gov/oact/STATS/table4c6.html https://www.ssa.gov/oact/STATS/table4c6.html
- jewayne 4y ago
  I love how, even for men, life expectancy doesn't fall below one year until age 113.
  - candiodari 4y ago
    Well that happens because the ones who die get excluded from the calculation. So it doesn't drop off nearly as fast. It's calculating P(death|age = N), not P(death|age <= N). Now luckily you can calculate the second one, by adding all values up to that age together. I would argue the value you're looking for, "when you die", is different still: P(death|age <= N, current_age=M), where M is your current age. You know, taking into account that you didn't die from sudden infant death syndrome or measles, or you wouldn't be here, but leaving everything in the future up to chance. To get that value, you should the odds of dying at all ages up to N, but only starting at your current age.
- LeifCarrotson 4y ago
  No, not exactly. Your chance of dying at year 80, per that table, is about 5% at 80, 15% at 90, and 30% at 100 (averaging for males and females). Not the same, and not 50. I think the observation they're trying to convey is that your expected number of years remaining goes down by much less than one year per year at those ages. A 90-year-old can expect to live for another 4.5 years, but on their 91st birthday, the chart surprisingly predicts not 3.5 but 4.2 years remaining. The number of expected years left drops more than 0.95 years per year until age 20, 0.9 years per year until age 40, down to 0.8 at 60, 0.5 at 80, and 0.1 at 100.
  - bena 4y ago
    Quirks of statistics. To have an average of 4.5, you need people to die before and after the mark. So a lot of people drop off between 91 and 92. But those who make it to 92 have about 4.2 years remaining. If you have a population of 100 people and 50 of them will live less than 1 year, and 50 of them will live an average of 10 years, that's 5.5 years on average for the whole population. But if you check that same population one year later, you will have 50 people who all live 9 years on average. You've managed to increase the average by eliminating the bottom. Same thing is happening here. And it's probably similar to professional sports careers. The average NFL career is about 3 years. However, if you make to 3 years, your average career length is about 7 years. We probably need more of a median or mode than a mean.
ddulaney 4y ago
This is not true. Either that it’s 50% at 80 or that it is flat after 80. Here’s an actuarial table: https://www.ssa.gov/oact/STATS/table4c6.html https://www.ssa.gov/oact/STATS/table4c6.html Annual chance of dying is 5% at 80 and continues rising every year (9% by 85, 16% by 90, 25% by 95, 35% by 100).
- JoeAltmaier 4y ago
  I see that! The chart I recall is clearly very out of date. Thanks!
Someone 4y ago
https://en.wikipedia.org/wiki/Gompertz–Makeham_law_of_mortality https://en.wikipedia.org/wiki/Gompertz–Makeham_law_of_mortal...: “The Gompertz–Makeham law states that the human death rate is the sum of an age-dependent component (the Gompertz function, named after Benjamin Gompertz), which increases exponentially with age and an age-independent component (the Makeham term, named after William Makeham). In a protected environment where external causes of death are rare (laboratory conditions, low mortality countries, etc.), the age-independent mortality component is often negligible. In this case the formula simplifies to a Gompertz law of mortality. In 1825, Benjamin Gompertz proposed an exponential increase in death rates with age. The Gompertz–Makeham law of mortality describes the age dynamics of human mortality rather accurately in the age window from about 30 to 80 years of age. You probably remembered the first part of the sentence following that: “At more advanced ages, some studies have found that death rates increase more slowly – a phenomenon known as the late-life mortality deceleration – but more recent studies disagree.” Even if that were true (something wikipedia contests. See also https://en.wikipedia.org/wiki/Late-life_mortality_deceleration https://en.wikipedia.org/wiki/Late-life_mortality_decelerati...), that doesn’t mean rate of death decreases, just that it increases slower than this model predicts.
sethammons 4y ago
to the downvoters: https://www.science.org/content/article/once-you-hit-age-aging-appears-stop https://www.science.org/content/article/once-you-hit-age-agi... At a certain point, humans appear to stop aging. Just it is at 105, not 80 :)