h***i 发帖数: 89031 | 1 结果经过元朝的90年残暴统治,两边又一边多了
你说说南蛮造谣怎么都不长脑子 |
b**g 发帖数: 949 | 2 assume 20 years per generation, 90 years means 4.5 generations. 4 kids per couple implies 2^(4.5) = 22. if 18 years per generation, 90 years means 5 generations, which implied 32 times as much population.
or, from another perspective, assume 4% annual growth rate, which implies 1.04 ^ 90 = 34.
if also assume the population in the south has reached the equilibrium (thus
constant). 20 to 30 times difference is certain a magnitude.
so this is not too rediculous.
【在 h***i 的大作中提到】 : 结果经过元朝的90年残暴统治,两边又一边多了 : 你说说南蛮造谣怎么都不长脑子
|
h***i 发帖数: 89031 | 3 扯
蒙古人的统治下,儿童存活率达到现代水平
果然很残暴的统治阿
implies
thus
【在 b**g 的大作中提到】 : assume 20 years per generation, 90 years means 4.5 generations. 4 kids per couple implies 2^(4.5) = 22. if 18 years per generation, 90 years means 5 generations, which implied 32 times as much population. : or, from another perspective, assume 4% annual growth rate, which implies 1.04 ^ 90 = 34. : if also assume the population in the south has reached the equilibrium (thus : constant). 20 to 30 times difference is certain a magnitude. : so this is not too rediculous.
|
b**g 发帖数: 949 | 4 if someone said 蒙古人的统治残暴, go find this guy and discuss with him NOT
me.
in ancient times, even in very recent past, it is very usual to give birth
to a lot of kids. the birth rate way higher than the actual growth rate.
the population growth rate after war is usually much higher than the normal
time.
【在 h***i 的大作中提到】 : 扯 : 蒙古人的统治下,儿童存活率达到现代水平 : 果然很残暴的统治阿 : : implies : thus
|
k***n 发帖数: 3158 | 5
couple implies 2^(4.5) = 22. if 18 years per generation, 90 years means 5
generations, which implied 32 times as much population.
1.04 ^ 90 = 34.
OK
thus
This assumption has a huge question mark. I would say it's invalid without
evidence.
【在 b**g 的大作中提到】 : assume 20 years per generation, 90 years means 4.5 generations. 4 kids per couple implies 2^(4.5) = 22. if 18 years per generation, 90 years means 5 generations, which implied 32 times as much population. : or, from another perspective, assume 4% annual growth rate, which implies 1.04 ^ 90 = 34. : if also assume the population in the south has reached the equilibrium (thus : constant). 20 to 30 times difference is certain a magnitude. : so this is not too rediculous.
|
b**g 发帖数: 949 | 6 forgot to ask this first: who when said "经过90年,两边又一边多了"? or you
just created this from air?
【在 h***i 的大作中提到】 : 结果经过元朝的90年残暴统治,两边又一边多了 : 你说说南蛮造谣怎么都不长脑子
|
b**g 发帖数: 949 | 7 i know. my purpose was to show what could happen in just 90 years.
and i have no intention to prove anything ... since the original statement
of LZ was not proved valid at the first place.
【在 k***n 的大作中提到】 : : couple implies 2^(4.5) = 22. if 18 years per generation, 90 years means 5 : generations, which implied 32 times as much population. : 1.04 ^ 90 = 34. : OK : thus : This assumption has a huge question mark. I would say it's invalid without : evidence.
|
s*****d 发帖数: 66 | 8 if also assume the population in the south has reached the equilibrium (thus
constant). 20 to 30 times difference is certain a magnitude. |
b**g 发帖数: 949 | 9 楼主所声称在元后期南北人口相同,这一点没有提供依据。所以谈论北方人口如何最后和南方相同缺乏可信的前提。我讨论的重点是北方是否可以实现人口呈一个数量级的增长。我的计算表明如果北方人口在元初只剩下原来的百分之三到五(即损失95%到97%),那么通过九十年就可以恢复原来的数量。当然这些假设没有多么严谨,只是个大概的估量,但是也可以说明问题。比如人口增长达到每一代翻一翻不太可能。但同时,人口的减少的估计也没有那么多。
thus
last
【在 s*****d 的大作中提到】 : if also assume the population in the south has reached the equilibrium (thus : constant). 20 to 30 times difference is certain a magnitude.
|