Fixing Demographics for GURPS BANESTORM

[DrTemp]

If the population in year n is X and the growth rate is A, then the population in year n+1 is X*(1+A).

Now, if you apply this simple formula iteratively, you might find that using, say, 100 (one hundred) initial colonists in 1800 and an annual growth rate of 7%, you'll have some 112 million Caitnessers in 2005. Anything between that and total extinction is possible.

Edit: Just checked the World Fact Book- an annual population growth rate of 2.8% (such as found in Benin, which has almost 6 children per woman) is perfectly within the human norm. Do the numbers- 2.8% will give you a a lot more population than 2.0%. For three million Caithnessers, about 12,000 initial colonists would suffice, for example.

[hal]

Originally Posted by DrTemp

If the population in year n is X and the growth rate is A, then the population in year n+1 is X*(1+A).

Now, if you apply this simple formula iteratively, you might find that using, say, 100 (one hundred) initial colonists in 1800 and an annual growth rate of 7%, you'll have some 112 million Caitnessers in 2005. Anything between that and total extinction is possible.

Edit: Just checked the World Fact Book- an annual population growth rate of 2.8% (such as found in Benin, which has almost 6 children per woman) is perfectly within the human norm. Do the numbers- 2.8% will give you a a lot more population than 2.0%. For three million Caithnessers, about 12,000 initial colonists would suffice, for example.

So, you're telling me that Caithness has what amounts to TL 7 medical knowledge instead of TL 3 medical knowledge. You are also saying that their growth rate is a little over 9 times that of Great Britian's from 1200 AD until approximately 1500 AD. Interesting.

[hal]

In thinking this over, I've come to the following conclusion.

1) either we have a TL3 growth rate marginally upgraded thanks to the spells like CURE DISEASE, HEAL PLANTS, BLESS PLANTS, etc or

2) We have a world where the growth rates are more modernistic, approaching modern technological states.

If we have option 1 - then the population growth rates are less than modern rates. Problem with that is, when using the lesser growth rates, 3 million population is too high for Caithness. It also permits the initial population of Megalos to be relatively large in 1800 AD.

If we choose option 2 - then the population of 3 million in Caithness is mathematically attainable, but the population of Megalos in 1800 AD is under 2 Million. You want to be able to have both a large population of Megalos in 1800 AD and stipulate that Caithness could have grown fast enough to have a 3 million population. Options 1 and 2 are mutually exclusive of each other.

So, despite the math models that you've been shown, despite the fact that I'm trying to blend both history with magic and still come up with something reasonable - you conclude that there is nothing wrong and that my points are invalid. OK, I know when to call it quits...

[Bruno]

Got a question: When you ran the math backwards to get the population of Megalos, did you realize that you'd get the population *sans* the settlers?

The modern population of Megalos is by definition decended from the nonsettlers, so just running the numbers backquards, and THEN subtracting the settlers, means that if you then run the numbers forwards you get less people in Megalos than there are now - you're double dipping.

[Ludek]

Originally Posted by hal

It occurs to me that my biggest issue with the history of Yrth is
that the density of population plus the history plus the actual population
figures seem all contradictory. Never one to point out a problem without
trying to find a solution, I think I've hit upon the solution neccessary
for "demographic realism".

Problem: in order to have a population of 3 million in 200 years, assuming
a 2% population growth rate, the colonizing population at start needed
to be 310,000. This is HORRENDOUSLY huge for the resources of DUKE of
Craine - ie, beyond his capability to set up on his own, let alone for a
3rd son. Using a 2% growth rate means that the population of Megalos
around 200 years in the past, would have been roughly 2 million population.
Clearly NOT realistic in light of the history of Megalos.

Well I think that assuminig uniform urowth rate in Megalos
across 200 years is wrong .. IMO Megalos had very high growth rate at it's
early history but it become much lower at it's latter history
(but probaly at it's beginig it was quite low becouse all human seletments
were just trying to survive and try to build up infrastructure)
Adding to this fact that humans were seletting in new land with foregin
microbal life (potential to many new diseases .. perchaps some of them may
be magicaly based ie. as part of it's efect invoking some magic based efects
on victims), competition with other sentient races (Orcs,Goblins, Halfings,
Kobolds and to some degree Elves and Dwarfes) and some of teh brinig
problay own diseases. With so many unknowns nubers you give for Megalos
population are quite prbable (so would figures biger
or smaler by fraction of x-.5-x2). It's not numbers nubers that are problem but
what you make of them. IMO barrinig or gettinig lighly on new
diseases Meglos population should be higer in 2000AD, if we assume significant
influence of new diseases we may get our target population.
Let's assume that your numbers as starting point so 200 years ago we had
5-9 milions of humans in Megalos(assuming taht in next 200 years they had
0.5-1%growth rate)and need around 200-400 thousands of setters in Caithiness
in order to have 3M population 200 years latter(with 2% growth).
It implies of course that Caithiness is growing much faster than Megalos but
you can fator in this taht during those 200 years Meglasoe would 'export'
significat portion of it's own growth to Caithiness (with would explain
in part it's own 0.5-1% efective growth). But why people would want to move?
My bet is on climate change resulting in series of bad harvest in Megalos
with might result in starvation in population dense areas of Megalos,
combined with outbreaks of diseases (badly fed peple are more prone to fall
ill). Combine this with charismatic and clewer leader who know value of good
propaganda of good air(no diseases), frefitle land in the west.
All you need initial and sucessfull expedition/expedions of 5-20 thousands
people followed by increasinig numbers after initial sucess. So in the end
you can get 200-300K (K=10^3) of initial population within 20-40 years(that's migration of 5-10K people per year on average).

DICLAIMER: I haven't read Banestorm yet.. it's all based on your figures
form other Banestorm thread and what I rember form old Yrth worldbook.
So if I made grevious error please point it, not pound me with it :P

[cccwebs]

Originally Posted by hal

So, you're telling me that Caithness has what amounts to TL 7 medical knowledge instead of TL 3 medical knowledge. You are also saying that their growth rate is a little over 9 times that of Great Britian's from 1200 AD until approximately 1500 AD. Interesting.

Any Magical healing would be better than TL7 medical knowledge. Assuming the amounts listed in Banestorm (2% population having minimal Magery, with possibly 1/10 of those capable of further training), a kingdom of 3 million will have at least 6000 people capable of learning healing spells which make TL7 healing look like "leeches and bloodletting" (possibly even more as the basic prerequisite in the chain for Minor Healing, which is Lend Energy only requires Magery 1 or Empathy). Add in Alchemy (which isn't factored with Magery, so there's no stats on how widely available that is) and what you have is a society which can all but eliminate disease, which leaves accidents, old age, and migration as the main factors for population decrease.

[DrTemp]

Originally Posted by hal

So, you're telling me that Caithness has what amounts to TL 7 medical knowledge instead of TL 3 medical knowledge. You are also saying that their growth rate is a little over 9 times that of Great Britian's from 1200 AD until approximately 1500 AD. Interesting.

Well, Benin isn't exactly state-of-the-art in medical technology- and Chaithness has certainly a lot of qualified alchemists, the ever underestimated magical art.

You cannot extrapolate from guessed medieval growth rates in England, because England was thoroughly settled by that time. Caithness not only had more resources available for feeding children, it should also have attracted new settlers over the centuries.

(Why is everybody only referring to England when talking about the middle ages? I mean, it's not as if it was more important than many other parts of Europe then...)

[hal]

Originally Posted by DrTemp

(Why is everybody only referring to England when talking about the middle ages? I mean, it's not as if it was more important than many other parts of Europe then...)

Most of the material I read is about the English Feudal system. It also has something of interest known as the Doomsday book - you ought to read it sometime ;)

As for England being settled circa 1200 AD? You were joking right?

[joewolz]

I'm not a math guy, but population is important...

In regard to caithness, wasn't it colonized for a period of 50 years or so? I haven't studied the demographic of the 1849 Gold Rush, nor the Gold rushes of the Yukon nor that of the Rockies...but couldn't that create huge numbers of colonists?

[Flyndaran]

Originally Posted by hal

Most of the material I read is about the English Feudal system. It also has something of interest known as the Doomsday book - you ought to read it sometime ;)

As for England being settled circa 1200 AD? You were joking right?

Hee. Domesday Book.
A Doomsday Book would cover plagues.