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Population replacement calculation.

Anonymous Sat 14 Mar 10:25:38 2020 No.11468405 View Reply Original Report

Quoted By: >>11468511 >>11469161

Suppose a disease came around that killed 20% of the worlds population every year. Accounting for the shortened life expectancy, how many children would the average female need to have over the course of her life to sustain the current population?

Anonymous

Anonymous Sat 14 Mar 2020 12:09:52 No.11468511 Report

Quoted By: >>11468631 >>11468771 >>11469102 >>11469161

>>11468405
A quick calculation would suggest each woman needs to have 1.5 children a year

7billion people, half men, half women
3.5b + 3.5b
Each year only 0.8 remain
3.5b*0.8 + 3.5b*0.8
Women limit the rate of child birth
3.5b*0.8 + 3.5b*0.8*n
where n is number of children per woman

3.5b*0.8 + 3.5b*0.8*n = 7b
the equation to solve to find the number of children for replacement, assuming death only occurs from the disease, and every female from 0-130 years old can have children

3.5b*0.8 + 3.5b*0.8*n = 7b
0.8 + 0.8n = 7b/3.5b = 2
0.8n = 1.2
n = 1.2/0.8
n = 1.5 children per female per year

Anonymous

Anonymous Sat 14 Mar 2020 13:26:44 No.11468631 Report

Quoted By:

>>11468511
So we would be fucked then

Anonymous

Anonymous Sat 14 Mar 2020 13:58:35 No.11468696 Report

Quoted By: >>11468821

Higher death rates tend to cause lower infection rates because people die before they spread it

Anonymous

Anonymous Sat 14 Mar 2020 14:42:29 No.11468771 Report

Quoted By: >>11468971

>>11468511
Holy Shit, 1.5 children per woman per year. That's insane.

Anonymous

Anonymous Sat 14 Mar 2020 15:03:20 No.11468821 Report

Quoted By:

>>11468696
No

Anonymous

Anonymous Sat 14 Mar 2020 15:06:11 No.11468826 Report

Quoted By:

>implying humanity is worth saving

Anonymous

Anonymous Sat 14 Mar 2020 16:13:23 No.11468971 Report

Quoted By:

>>11468771
it's right at the limit of feasibility though, considering the gestation length. There would need to be hormones taken to increase the rate of twins.

Anonymous

Anonymous Sat 14 Mar 2020 16:23:07 No.11468995 Report

Quoted By: >>11469011

It's honestly better for the environment if we lose a few billion, though.

Anonymous

Anonymous Sat 14 Mar 2020 16:29:24 No.11469011 Report

Quoted By:

>>11468995
no disagreements there, also it would improve worker conditions too which will help to reduce suicide rates. Maybe the disease will peter out once the population becomes self isolating, like how antarctic explorers no longer caught colds after their long voyage.

Anonymous

Anonymous Sat 14 Mar 2020 16:36:00 No.11469024 Report

Quoted By:

>population culled a bit
>everything is a little nicer, less traffic, etc
>society finally values population control as a virtue

Anonymous

Anonymous Sat 14 Mar 2020 17:13:41 No.11469102 Report

Quoted By:

>>11468511
kek, nice troll

Anonymous

Anonymous Sat 14 Mar 2020 17:40:31 No.11469161 Report

Quoted By:

>>11468405
>>11468511
A disease that kills 20%each year kills 20 of each 100, leaving 80 alive, 40 of those are women who need to have 20 children each year, which gives me one child per 2 years. Is that wrong?

Anonymous

Anonymous Sat 14 Mar 2020 19:21:34 No.11469339 Report

Quoted By:

I ran the numbers again. in a population of 100 average persons 12.5% of women are at childbearing age, so that subset would have to produce 20 a year or 1.6 persons.
Then consider infant mortality. if 20 children are born in a year 16 of them will be alive after a year due to the attrition rate of the disease, 12.8 after the second year 10.24 after the third year 8.92 after the fourth, 6.55 after the fifth, 5.24 after the sixth, 4.19 after the seventh, 3.3 after the eighth year, 2.64 after the ninth, 2.1 after the tenth year, 1.6 after the 11th, 1.35 after the 12th, 1.08 after the thirteenth and then 0.86 after the their fourteenth birthday, numbers under one means their all dead.

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