An Evil Guest science errors

Jeff Wilson · 04 Jan 2010, 17:21 · from 2010-January.txt.gz

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From: jwilson at io.com (Jeff Wilson)
Date: Mon, 04 Jan 2010 11:21:27 -0600
Subject: (urth) An Evil Guest science errors
In-Reply-To: <cbf55b101001040807k746b10c5r263738f07e799eee at mail.gmail.com>
References: <cbf55b101001040807k746b10c5r263738f07e799eee at mail.gmail.com>
Message-ID: <4B422397.6010402 at io.com>

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]


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)

or

click View | click Scientific
.9997 [x^y] 100 [=]		(for CALC.EXE)



-- 
Jeff Wilson - jwilson at io.com
IEEE Student Chapter Blog at
< http://ieeetamut.org >

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