PDA

View Full Version : fascinating link on demographics



Spazzle
05-29-2009, 05:02 PM
I was trying to come up with numbers and such for my campaign in terms of populations and city sizes. I ran across this link - its fascinating!

Figured I would pass it along as it directly relates to folks trying to create fanciful maps, and it might help to have a bit of perspective on populations, city sizes, number of cities, and amount of land devoted to farming to support each city.

http://www.io.com/~sjohn/demog.htm

Cheers,

Richard

PS - if this was shared previously, sorry for the repeat!

msa
05-29-2009, 05:39 PM
Great link!

Gandwarf
05-29-2009, 06:29 PM
Yeah, it's quite a famous article.

Midgardsormr
05-30-2009, 09:47 AM
Incidentally, the author of that article is a sometime poster here. His user name is Ghalev. He hasn't posted since August, but he promised to come by from time to time to see what's going on.

So if you see his name in a post somewhere, hit him with your rep stick to thank him for that article!

Ramah
06-01-2009, 06:19 AM
That is a brilliant article. Thanks for posting the link to that. :)

alaskanflyboy
06-02-2009, 01:21 PM
That's pretty well done. Now I find myself wanting to find a modern/sci-fi version.

Spazzle
06-02-2009, 06:20 PM
Sci Fi may be a bit tough - as the variables could (potentially) have no limits.

For example, if you had a miracle protein plant that grew itself in a pot with little effort involved, it might seriously reduce any need for local farm land. Plus the advent of modern technology would mean food could theoretically come from anywhere, even off planet.

That said, current trends could probably be distilled into basic guidelines for modern games and the ratios of residences/businesses could closely match real world examples.

su_liam
06-03-2009, 01:34 AM
You could set limits on that super-plant based on energy requirements. Best-case scenario a 5000 calorie diet requires no less than 5000 calories of energy to produce. If that comes from solar energy, you could set a maximum yield per acre. At perfect efficiency with the amount of Solar energy impinging on the outer atmosphere one acre could produce 113.6 million kilocalories. Given a 2000 calorie(actually kcal) diet, that would feed 56,788 people more or less. A pretty extreme limit, but still a limit.

alaskanflyboy
06-03-2009, 11:29 AM
I lumped modern and sci-fi together as sci-fi generally sticks close to modern considerations. Whether the food comes from Mars or Argentina, cities would likely develop in a similar manner to modern, but the support values for the various industries would be similar enough to modern that one could tweak the values to what ever degree they needed to come up with their level of development in sci-fi. I just know there are services and industries in existence today that weren't in the medieval world, such as groceries, fuel stations, and power plants. I wouldn't even know where to begin in considering a rough number of their support values. And, yes, I know that power-plants would likely increase in sci-fi, but having a modern base-line would be helpful to work with.

Spazzle
06-03-2009, 12:53 PM
A pretty extreme limit, but still a limit.

True, though the only thing that pretty much makes the limits infinite is transportation - one planet could convievably produce no food, yet sustain millions if all their food was transported from another planet.


I just know there are services and industries in existence today that weren't in the medieval world, such as groceries, fuel stations, and power plants. I wouldn't even know where to begin in considering a rough number of their support values.

This is also pretty tricky. For example, if you had an automobile sales business, it could be built in a small town of 3,000. Yet it depends on someone somwhere else to actually make the autos as the town couldn't support the industry by itself.

I think that's what makes the "fantasy" element a little easier to manage, because we have hard values about how much land it takes to grow x amount of calories, which can support x population. Given x population, we could support Y numbers of industries/businesses. Since there was no global economy, and local economies were pretty much limited to their own villages, each village was a microcosm and distinct.

Of course, in any fantasy setting we could propose almost any combination of support structures (magical/natural) that would invalidate "real world" demographics. However, I think its easier to work with those numbers than modern/sci fi equivalents.

I'd still be curious to see what would be determined as a baseline - however inaccurate it may be. It can always serve as a starting point to build on.

What funny is that rarely (for understandable reasons) do fiction writers dwell on these things. About the only show I know that dealt with real-world needs was Star Trek:Voyager, and that was simply due to the fact that not being able to return to a nearby starbase to resupply had a serious effect on the ship's stores. It was only dealt with superficially, but at least they acknowledged the fact that the food had to come from somewhere. :D

alaskanflyboy
06-03-2009, 01:33 PM
As you say, things like manufacture are global as are things like food. I'm more curious in terms of those things common to all towns. Things like schools, grocery stores, pharmacies (seems like one on every corner these days), gas-stations, theaters, malls, fast-food restaurants, hospitals, clinics, etc. Though, even with food and goods potentially being built on other planets, countries, or towns; it would be nice to also come up with some idea of the consumption of places for those of us that world-build.

Granted I tend to enjoy complexity, I'm sure there are others that would find it interesting to see what could be developed.

And to go with the original post, I found that Welsh Piper made a generator based on that very article. http://welshpiper.com/content/low-fantasy-population-generator

Spazzle
06-04-2009, 11:13 AM
I'd be curious to see what could be developed as well. But then again, I'm a number's geek!

Great calculator, btw. Makes running the numbers rather easy...

alaskanflyboy
06-04-2009, 12:30 PM
I'd be curious to see what could be developed as well. But then again, I'm a number's geek!

I am as well, especially given my current project of mapping and building a world that is terraformed and inhabited by lost colonists. The planet was created in AstroSynthesis and the surface in Fractal Terrains Pro with some Wilbur editing, so I already had some stats. But I went further and calculated things out that neither program automatically gives, such as speed in orbit and rotation, the planet's volume, surface area, perihelion and aphelion, and longitude of ascending node. So, given my nearly psychotic inclination towards numbers, trying to estimate their needs in a believable way would be a plus.

The setting also has a terraformed Mars involved so there is trade between Mars and Earth, but no highly perishable goods such as fresh fruit. Though, even with that constraint, it's still considered too expensive to ship food except in emergency. It's still given that all travel is at sub-light (yet faster than modern vessels) with inter-system travel run through naturally occurring nodes as is done in Wing Commander and Free Space, which accounts for the constraint.

Midgardsormr
06-04-2009, 07:13 PM
I think it was Sigurd who embarked on an interesting demographic study of Herefordshire. That kind of approach might lend itself to developing some numbers that could then be used as generalizations. A study of a major metropolitan area and one of a nearby agrarian community together might provide a great deal of data that could be used in a number of ways.

Spazzle
06-05-2009, 11:50 AM
I'm also thinking that, at least in terms of modern numbers, there's most likely real world research already done for business development and marketing industries. That said, getting your hands on that data may be more difficult than we imagine... :-)

Karro
06-05-2009, 02:05 PM
I'm also thinking that, at least in terms of modern numbers, there's most likely real world research already done for business development and marketing industries. That said, getting your hands on that data may be more difficult than we imagine... :-)

If, by more difficult, you mean more costly. There's marketing research firms that have data on this kind of thing, but that won't run cheap - particularly since you'd probably have to pay separately for each industry's data.

Some data might also be available through the local SBA, or through the business development outreach of your local business college/university, though it won't be as sofisticated there, and will probably be focused primarily on the local market. I'd imagine you'd still pay for that, as well.

Spazzle
06-05-2009, 03:41 PM
That's what I was thinking. I did manage to find some numbers available for free via local governments, but you'd have to extrapolate the information and make some general assumptions for it work. From what I could find, it was VERY market specific - but there is hope, if someone had the time and inclination.

Midgardsormr
06-05-2009, 10:35 PM
For more generalized info (that is, applicable to the country at large rather than specific markets), try the U.S. Chamber of Commerce. There are a few papers there that might be of use.

alaskanflyboy
06-06-2009, 03:05 AM
This is starting to sound like a community/committee project. I don't even know if it'd need to be so much realistic as it was plausible, but a handy reference to give a realistic feel. We all know that the world differs between countries, which might be something to add as a general modifier between first, second, and third world. Salt and pepper to taste. That's mostly what I'm interested in, a baseline that makes things feel real to the outside observers who look at a fictional world setting.

The town I went to high school in has a population of just over two-thousand and contains one grocery store, two pharmacies (one of which also sells art supplies), four gas stations (two with mini-marts), one hardware store, two bars, one butcher shop, one barber shop, at least five coffee shops, two bakeries, one elementary school, one middle school, and one high school, two small car lots, three auto repair shops, two auto-part stores, a post office, at least eight churches, two parks, three spa/salons, a public library, one fire station, one police station, one hospital, two clinics, at least three apartment complexes, and that's all that comes immediately to mind.

Spazzle
06-06-2009, 10:04 PM
If this was turned into a project, I'd definitely be up for helping with research and calculations.

Karro
06-09-2009, 09:22 AM
If/when I had time, I'd be interested in contributing research/data. The problem is the having of that time, but it would be an interesting project to contribute to.

Caleb
06-09-2009, 04:46 PM
Yes, thank you for the link. This is beyond helpful, and it really gives perspective to how the medieval era worked. Though of course, this is for "our real" world, so for me, I cannot follow this to the most strict definition. Because of magic, and other supernatural feats possible in most fantasy worlds, demographics will have a curve to them.

But anyway, this is amazingly helpful, it serves as a perfect foundation to build any medieval world.

Thanks for the link,
Caleb

Notsonoble
06-18-2009, 09:40 PM
Kicking the topic back to the op:

I've been using stuff from this particular article for a while trying to build my campaign settings... but I'm having trouble getting a good idea of how to factor in stuff like magical assistance, the type of leadership the kingdom has... and some of the other things he mentions. Also, my 190K sq mi area that's had a stable ruling system for 350 years is generating a 11million population (give or take 2 mill for things like wars and such), even with really low population densities... This makes for some absolutely-freakin-huge largest settlements...

My current attempt is taking "Govt Nature", Land Quality, and Magical Influence, rating them 1-5, and using 6d4*(Events+(gov nature+land quality+magical influence/3)+(age/100) to get a pop/square mile... it seems to be generating reasonable population densities... but pop totals with all the rest come out kinda crazy...

Midgardsormr
06-19-2009, 10:08 AM
11 milllion isn't unreasonable for that land area under a stable government. It's a little smaller than France, which had similar extents in the middle ages as it does today. A 1328 census estimated the population of France at 17.6 million, although "other authorities" suggest a number closer to 15 million, around 90% of which were rural.

That census followed a relatively peaceful era, about 300 years following the surcease of raids from both Vikings and Muslims.

The black death and a few wars reduced France's population thereafter to about 10 million in 1450, which is still in line with the calculator's prediction.

Data taken from the article "Population and Demography" by William Percy, jr in Medieval France: an Encyclopedia, by William W Kibler and Grover A Zinn, editors.

Notsonoble
06-20-2009, 02:46 PM
Okay, so if they are reasonable, I suppose I'll just go with them... It seemed odd, since his example wasn't all that much smaller of an area, but he had something like 8 million... and a 5% urban population. I seem to be getting (based on his city/town breakdowns) 1.5% to maybe 2.5% urban populations...

Notsonoble
08-20-2009, 07:44 PM
so that 11 mi number, well when you break down his stuff in more detail about distance between towns citys and such... I noticed that even just blowing concentrations away and spreading my communities out evenly in this one country... I'd get a community every 13 miles in any direction!? The pop numbers make since, but the number of communities seems to really have crapped out...

13 miles apart as an average makes since if you do the 2/3 populated 1/3 wilderness... but for that I got a community every 8 miles

Overland movement for a human in DND is 24 miles a day, this is actually pretty reasonable... I could probably (despite being in horrid shape) make 15-18 in a day pretty easy... and most military personnel can beat 24/day... so this would mean that a character could run across on average 3 communities a day on the road???

I'm thinking that it's not really the math's fault, its either something I screwed up... or simply not taking in to effect the idea that magic would have an effect of +100 years technology would... and cause a bit more concentration in places... So I'm thinking about simply halving the numbers. (not pop, but separate communities)

Also, again, on doing civilizations with lower populations (under the 5 million mark it seems so far) the distribution makes a lot more since... which is why I think I screwed up the math somewhere, and its small enough a goof that it doesn't show up on smaller populations...

Midgardsormr
08-20-2009, 11:34 PM
Have you also referenced Sigurd's in depth study of Herefordshire?
http://www.cartographersguild.com/showthread.php?t=3391