An Evil Guest science errors

From: "Gwern Branwen" <gwern0 at gmail.com> Sent: Monday, January 04, 2010 10:07 AM To: "The Urth Mailing List" <urth at lists.urth.net> Subject: (urth) An Evil Guest science errors I forgot to include this in my tone email, but another thing that bothered me coming from an engineer is the apparent sloppiness with his scientific assertions. Reis claims that even if humans didn't age, we'd still only get 2 or 300 years because of accidents and murders and self-slaughter. This is a classically conservative argument against being interested in curing aging - you're going to die anyway, and soon - but as far as I can tell, his numbers are just wrong. I have seen statistics to the effect that a 12 year old who stopped aging could expect a median lifespan of >1000 years before disease or something else finally got her. But the mortality rates for young people in general are low enough that 2 or 300 years is ridiculously too little, and we can see this very easily, http://gravityandlevity.wordpress.com/2009/07/08/your-body-wasnt-built-to-last-a-lesson-from-human-mortality-rates/ mentions that 1/3000 or 0.03% of 25 year-olds will die age 25. (Seems reasonable to me.) If we assume a cohort of 10x people, and each year 0.03% of them die, then 1000 years from now, 7.4x will still be alive. 300 years from now, 9.15x will still be alive, and 200 years will see 9.42x. It's a low death rate! Even a little basic figuring would have show 2-300 years to be absurd. And we can't make the excuse that Wolfe was estimating from the mid-40s ages of the protagonists, since the mortality rate cited for 42 year-olds is 1/750 or 0.13%. Plug in the 1/750 to the formula and ask for 300 years from now, and 6.7x are still alive. Heck, 2.6x are still alive 1000 years from now. 7/10ths or 3/10ths odds are not grounds for despair and dismissal. I'm calculating this in a Haskell REPL, GHCi, using this expression for 100 years: 'take 100 $ iterate (\x -> x - (x * 0.0003)) 10' You can see that each step is a year, and each step subtracts 0.03% of the previous year's population-total: [10.0,9.997,9.9940009,9.99100269973,9.98800539892008,9.985008997300405,9.982013494601215,9.979018890552835,9.97602518488567,9.973032377330204,9.970040467617006,9.96704945547672,9.964059340640077,9.961070122837885,9.958081801801034,9.955094377260494,9.952107848947316,9.949122216592631,9.946137479927653,9.943153638683675,9.940170692592071,9.937188641384294,9.934207484791878,9.931227222546442,9.928247854379677,9.925269380023364,9.922291799209358,9.919315111669595,9.916339317136094,9.913364415340952,9.91039040601635,9.907417288894546,9.904445063707877,9.901473730188766,9.898503288069708,9.895533737083287,9.892565076962162,9.889597307439074,9.886630428246841,9.883664439118366,9.88069933978663,9.877735129984694,9.874771809445699,9.871809377902865,9.868847835089495,9.865887180738968,9.862927414584746,9.859968536360372,9.857010545799463,9.854053442635724,9.851097226602933,9.848141897434953,9.845187454865723,9.842233898629264,9.839281228459674,9.836329444091136,9.83337854525791,9.8304 28531694333,9.827479403134824,9.824531159313883,9.821583799966088,9.8186373248261,9.815691733628652,9.812747026108564,9.809803202000731,9.80686026104013,9.803918202961817,9.80097702750093,9.79803673439268,9.795097323372362,9.79215879417535,9.789221146537097,9.786284380193136,9.783348494879078,9.780413490330615,9.777479366283515,9.77454612247363,9.771613758636889,9.768682274509297,9.765751669826944,9.762821944325996,9.759893097742697,9.756965129813375,9.75403804027443,9.751111828862348,9.74818649531369,9.745262039365095,9.742338460753285,9.739415759215058,9.736493934487294,9.733572986306948,9.730652914411056,9.727733718536733,9.724815398421171,9.721897953801644,9.718981384415503,9.716065690000178,9.713150870293179,9.71023692503209,9.70732385395458] -- gwern _______________________________________________

Perhaps Chase is using different variables based on empirical data in other non-aging cultures. Perhaps un-aging cultures tend toward more violence and risk. And for self-slaughter, we're talking suicide. We simply cannot know the rates of suicide in cultures where life goes on and on. -------------------------------------------------- From: "Gwern Branwen" <gwern0 at gmail.com> Sent: Monday, January 04, 2010 10:07 AM To: "The Urth Mailing List" <urth at lists.urth.net> Subject: (urth) An Evil Guest science errors

I forgot to include this in my tone email, but another thing that bothered me coming from an engineer is the apparent sloppiness with his scientific assertions. Reis claims that even if humans didn't age, we'd still only get 2 or 300 years because of accidents and murders and self-slaughter. This is a classically conservative argument against being interested in curing aging - you're going to die anyway, and soon - but as far as I can tell, his numbers are just wrong. I have seen statistics to the effect that a 12 year old who stopped aging could expect a median lifespan of >1000 years before disease or something else finally got her. But the mortality rates for young people in general are low enough that 2 or 300 years is ridiculously too little, and we can see this very easily, http://gravityandlevity.wordpress.com/2009/07/08/your-body-wasnt-built-to-last-a-lesson-from-human-mortality-rates/ mentions that 1/3000 or 0.03% of 25 year-olds will die age 25. (Seems reasonable to me.) If we assume a cohort of 10x people, and each year 0.03% of them die, then 1000 years from now, 7.4x will still be alive. 300 years from now, 9.15x will still be alive, and 200 years will see 9.42x. It's a low death rate! Even a little basic figuring would have show 2-300 years to be absurd. And we can't make the excuse that Wolfe was estimating from the mid-40s ages of the protagonists, since the mortality rate cited for 42 year-olds is 1/750 or 0.13%. Plug in the 1/750 to the formula and ask for 300 years from now, and 6.7x are still alive. Heck, 2.6x are still alive 1000 years from now. 7/10ths or 3/10ths odds are not grounds for despair and dismissal. I'm calculating this in a Haskell REPL, GHCi, using this expression for 100 years: 'take 100 $ iterate (\x -> x - (x * 0.0003)) 10' You can see that each step is a year, and each step subtracts 0.03% of the previous year's population-total: [10.0,9.997,9.9940009,9.99100269973,9.98800539892008,9.985008997300405,9.982013494601215,9.979018890552835,9.97602518488567,9.973032377330204,9.970040467617006,9.96704945547672,9.964059340640077,9.961070122837885,9.958081801801034,9.955094377260494,9.952107848947316,9.949122216592631,9.946137479927653,9.943153638683675,9.940170692592071,9.937188641384294,9.934207484791878,9.931227222546442,9.928247854379677,9.925269380023364,9.922291799209358,9.919315111669595,9.916339317136094,9.913364415340952,9.91039040601635,9.907417288894546,9.904445063707877,9.901473730188766,9.898503288069708,9.895533737083287,9.892565076962162,9.889597307439074,9.886630428246841,9.883664439118366,9.88069933978663,9.877735129984694,9.874771809445699,9.871809377902865,9.868847835089495,9.865887180738968,9.862927414584746,9.859968536360372,9.857010545799463,9.854053442635724,9.851097226602933,9.848141897434953,9.845187454865723,9.842233898629264,9.839281228459674,9.836329444091136,9.83337854525791,9.83 04 28531694333,9.827479403134824,9.824531159313883,9.821583799966088,9.8186373248261,9.815691733628652,9.812747026108564,9.809803202000731,9.80686026104013,9.803918202961817,9.80097702750093,9.79803673439268,9.795097323372362,9.79215879417535,9.789221146537097,9.786284380193136,9.783348494879078,9.780413490330615,9.777479366283515,9.77454612247363,9.771613758636889,9.768682274509297,9.765751669826944,9.762821944325996,9.759893097742697,9.756965129813375,9.75403804027443,9.751111828862348,9.74818649531369,9.745262039365095,9.742338460753285,9.739415759215058,9.736493934487294,9.733572986306948,9.730652914411056,9.727733718536733,9.724815398421171,9.721897953801644,9.718981384415503,9.716065690000178,9.713150870293179,9.71023692503209,9.70732385395458] -- gwern _______________________________________________

On 1/4/2010 10:07 AM, Gwern Branwen wrote: I'm calculating this in a Haskell REPL, GHCi, using this expression for 100 years: 'take 100 $ iterate (\x -> x - (x * 0.0003)) 10' You can see that each step is a year, and each step subtracts 0.03% of the previous year's population-total: [10.0,9.997,9.9940009,9.99100269973,9.98800539892008,9.985008997300405,9.982013494601215,9.979018890552835,9.97602518488567,9.973032377330204,9.970040467617006,9.96704945547672,9.964059340640077,9.961070122837885,9.958081801801034,9.955094377260494,9.952107848947316,9.949122216592631,9.946137479927653,9.943153638683675,9.940170692592071,9.937188641384294,9.934207484791878,9.931227222546442,9.928247854379677,9.925269380023364,9.922291799209358,9.919315111669595,9.916339317136094,9.913364415340952,9.91039040601635,9.907417288894546,9.904445063707877,9.901473730188766,9.898503288069708,9.895533737083287,9.892565076962162,9.889597307439074,9.886630428246841,9.883664439118366,9.88069933978663,9.877735129984694,9.874771809445699,9.871809377902865,9.868847835089495,9.865887180738968,9.862927414584746,9.859968536360372,9.857010545799463,9.854053442635724,9.851097226602933,9.848141897434953,9.845187454865723,9.842233898629264,9.839281228459674,9.836329444091136,9.83337854525791,9.8 304 28531694333,9.827479403134824,9.824531159313883,9.821583799966088,9.8186373248261,9.815691733628652,9.812747026108564,9.809803202000731,9.80686026104013,9.803918202961817,9.80097702750093,9.79803673439268,9.795097323372362,9.79215879417535,9.789221146537097,9.786284380193136,9.783348494879078,9.780413490330615,9.777479366283515,9.77454612247363,9.771613758636889,9.768682274509297,9.765751669826944,9.762821944325996,9.759893097742697,9.756965129813375,9.75403804027443,9.751111828862348,9.74818649531369,9.745262039365095,9.742338460753285,9.739415759215058,9.736493934487294,9.733572986306948,9.730652914411056,9.727733718536733,9.724815398421171,9.721897953801644,9.718981384415503,9.716065690000178,9.713150870293179,9.71023692503209,9.70732385395458]

On Mon, Jan 4, 2010 at 11:28 AM, James Wynn <crushtv at gmail.com> wrote: Perhaps Chase is using different variables based on empirical data in other non-aging cultures.

Perhaps un-aging cultures tend toward more violence and risk.

And for self-slaughter, we're talking suicide. We simply cannot know the rates of suicide in cultures where life goes on and on.

On Mon, Jan 4, 2010 at 11:43 AM, <brunians at brunians.org> wrote: When you are talking about something totally speculative, you can make up whatever result you like, basically, and justify your assumptions however you like. Hey, the Shivapuri Baba took up smoking at the age of 107, and died at the age of 137.

On Mon, Jan 4, 2010 at 12:21 PM, Jeff Wilson <jwilson at io.com> wrote: Those more modestly equiped with Excel or Windows' built-in CALC.EXE can check this by treating it as a survival chance of .9997 per year, and raise that value to (for example) 100 years with =0.9997^100 (for Excel)

Gwern Branwen wrote: The intuitive arguments are for exactly the opposite: if your lifespan is indefinitely long, you jeopardize indefinitely many years with violence or risk, whereas with aging, no matter the risk you take you can lose no more than 120 years of life. A ceiling on losses encourages risk-taking. (Consider recent financial bail-outs...)