Explanation of population growth and squalor

[Quinn Inuit]

This post is epic: http://www.twcenter.net/forums/showt...035#post802035

[Quinn Inuit]

Here are my thoughts so far. Warning: this will ramble.

Chart from linked post:
6,000 . . . . 2% . . . . -20%
12,000 . . . 4% . . . . -40%
15,000 . . . 5% . . . . -50%
18,000 . . . 6% . . . . -60%
21,000 . . . 7% . . . . -70%
24,000 . . . 8% . . . . -80% <--- HUGE CITY
25,500 . . . 8.5% . . . -85%
27,000 . . . 9% . . . . -90%

I'm not going to worry about happiness. With the multi-temple-mod installed (it was in RTR6G), that's not a problem.

Health buildings are dangerous, but I don't want to remove them. I suspect the game uses them when determining the likelihood of a plague.

We want cities growing only slightly faster than they need to. We also don't want huge cities cropping up everywhere.

You only have 1% squalor at 3K. The interesting thing here is that the base fertility bonuses (even at their new low levels of 1-3) are going to have a heavy effect through 6K. So I think we actually don't want the low-level buildings giving more than a couple of pop bonuses. Maybe limit it to the farm bonuses. That'll slow growth through 6K. Then again, you don't have a lot of people at that level, so growth will be slow, regardless. Hmmm...eh, the basic fertility bonuses will help the most at the lowest levels where it'll be needed the most, so I don't think I'll worry about it.

I'm not going to control for pop growth bonuses from ancillaries or skills. That'll be a wildcard. Where's the fun in controlling for everything?

I'm worried the AI will mess up all of this by taxing too much. We'll cross that bridge when we come to it, though.

Draft pop growth (notation = PG) plan:
Squalor numbers _doubled_ so they match the pop growth increments. When a settlement size range encompasses multiple squalor levels, the higher is used. Notation = Sq
X = 1, 2, or 3 (depending on the fertility level)
Y = Other PG bonuses, like markets
F = farming level. Capped at 4 in this chart because the fifth level will be available at large city level.
Village: just fertility bonus X
Town: X + 1 level F = 2-4, with most settlements at 3. Squalor = 0.
Large Town: X + 2F + 1Y - Sq2 = X + 1 PG, with most settlements at 3.
City: X + 3F + 3Y - Sq6 = X PG, with most settlements at 2. This is where growth starts to slow for the low-fertility areas
Large City: X + 4F + 1F + 8Y - Sq14 = X-1 PG. Low fertility areas therefore stop at city level.
Huge City: X + 4F + 1F + 10Y - Sq18 = X-1 PG.

I'm pretty sure I did that wrong, but I need to go to bed now. I'll work on it again tomorrow. If anyone has any suggestions, feel free to post them.

[Quinn Inuit]

Update:
Draft pop growth (notation = PG) plan:
Squalor numbers _doubled_ so they match the pop growth increments.
When a settlement size range encompasses multiple squalor levels, the higher is used. Notation = Sq

X = 1, 2, or 3 (depending on the fertility level)
Y = Other PG bonuses, like markets
P = Public health
F = farming level. Capped at 4 in this chart because the fifth level will be available at large city level.
Village: just fertility bonus X
Town: X + 1 level F = 2-4, with most settlements at 3. Squalor = 0.
Large Town: X + 2F + 1Y - Sq2 = X + 1 PG, with most settlements at 3.
City: X + 3F + 3Y - Sq6 = X PG, with most settlements at 2. This is where growth starts to slow for the low-fertility areas
Large City: X + 4F + 1F + 8Y - Sq14 = X-1 PG. Low fertility areas therefore stop at city level.
Huge City: X + 4F + 1F + 11Y - Sq18 = X-2 PG.


So, what to make the Ys?
Large Town: 1Y
1 PG from sewers

City: 3Y
1 PG from market
2 PG from public health building

Large City: 8Y
2 PG from trade building
3 PG from public health building
1 PG from infrastructure building
2 PG from additional farm level (double farm bonus of last two levels)

Huge City: 11Y
2 PG from trade building
4 PG from public health building
2 PG from infrastructure buildings
2 PG from additional farm level (double farm bonus of last two levels)
1 PG from high temple

Only Romans will get aqueducts, but other civilized factions will get an additional bonus from a trade building of some sort.
Infrastructure buildings are to be named later.
Major trade hubs will have a separate bonus to be determined later.

[Carados]

It took me a short while to read over it several times, but I got it eventually. Nice.

Btw, squalor contributes to public order so we might want to give buildings suitable bonuses to counteract that. As in, large cities look to be getting a -140 to public order here. That's not including corruption and other negatives. It might be an idea to construct a public order equation to go along with these.








And I still think public baths shouldn't give a public health bonus

[Quinn Inuit]

Heh, you think was bad, try writing it. ^_^ That took awhile.

According to the link at the top, the huge cities will only get a -90%, but that's not counting other negatives. You're probably right that we should look into a PO equation, too.

PO is fine at lower levels. The temples are pretty much bottom-loaded. The trick is at the higher levels. I'm guessing most factions can count on maybe 55% in temple boosts, then a couple of happiness points from the law, theater, games, or tavern buildings. That gets you up to, say, 65%. Then we can add a boost to all of the sewer buildings, along with a small boost to the walls. After that, they're on their own.


I know, but I still like the baths. Besides, what could we replace them with?

[Carados]

I'm fairly good with mathematics, I just have great trouble reading it unless you put in an uber word equation to start it off (so rather than letters, you put the actual word in).

You said you'll increase squalor to match growth so those numbers are actually far higher, no? This is what I'm not quite getting, it's supposed to be on a linear scale (every 3000 people in your settlement gives -1% population gorwth in squalor and -10% in public order), but in your equations those numbers are much higher (14 squalor in large cities, -14% growth and -140% public order). Squalor is manageable at the low levels but it reaches very high values at larger settlement sizes.

A rough public order equation is something like this:
Public Order = [(Influence*5%) + (happiness*5%) + (law*5%) + (entertainment*5%)] - [(squalor*10%) - (unrest*5%) - (corruption*5%) - (culture penalty*5%) - (distance to capital*5%) - (tax%{linked to unrest?})]

The most important number is squalor. If we assume a large city of 12'000, then we have an instant -140% (or -40%, depending on how squalor will actually be worked out). If we assume 40%, then at normal tax rate we would need to have 40% of influence, happiness, law, entertainment etc to have a public order of 100%. Off the top of my head, these include arenas (5% happiness + extra entertainment), acadamies (5% law), execution squares (10% law?), odeons (5% happiness), large temples (15% happiness), up to five minor temples (0-25% happiness). Assuming everything is built, then a settlement reaching 12'000 (so it doesn't have the government building) will have around 110% public order bonus [no one faction can build all of these buildings]. If we take off the 40% from squalor then we have a net of 80% thus resulting in a city with 170% public order. This is without a governor nor a garrison. Even if we were to take into account other negative public order problems, there is 95% to lose before it gets dangerous.

If, however, the value of squalor is in fact 140%, then we get a more interesting situation. With all the buildings public order takes a 20% hit which drops the net value to 70%. A garrison and governor can easily offset this deficit, but there is a very good chance that the other factors that I've not included (corruption, unrest, culture) are taking off public order at a sufficient rate to cause you to keep an eye on the city.

Roughly speaking, anyway.


As for baths. I've no idea. Though I do wonder if giving a happiness, public health and squalor value would be the right way to do things. Sure, you can wash things away off your skin but there are still loads of bacteria floating around in the water vapour. Breath that in and you're stuck, you can't wash it away (though you could try eating honey? ). Chest infections are worse than smelling bad. The happiness is for the social experience which does have benefits.

[Juan_de_Marco]

Hence the emphasis on hot/cold baths, and scraping off dirt. And lets not forget the game simulates with such a building a comparison to other cultures. (in the hygienic sense, it is better than... washing in the same spot as where your waste goes?)

[Quinn Inuit]

I see the problem here. First, I probably wasn't clear enough about the squalor number. That's been doubled, so it matches the population growth increments. Halve it to get the squalor percentage. Second, the number at any particular level represents the highest squalor a city at that level can get. So the maximum squalor a large city could get would be 7% at the 18k mark...

Oh, blast. I think I did that slightly wrong. The squalor point comes on at the 1,500 mark, not two at the 3,000 mark. Hmmm...we may need to add one growth level to the city and large city levels, then.

[Juan_de_Marco]

Why would you do that? -Maybe you shouldn't. A city does not 'naturally grow'.

Because this way [with handicapped growth] cities will not grow 'to the next level', unless they have had an excellent administrator in the past. Someone exceptionally skilled at, I don't know, taxing the latrines, urban planning, funding new housing projects for the poor, devising a new agricultural system, or having a religion that promotes large families... In fact if you could model it to cap below the expansion threshold, you would be simulating that a population always falls to an equilibrium without 'special plans'. Quite realistic, I'd say.

This may be in fact only a problem for the AI, as they cannot 'steer' this development quite so good as a human player. But given that the timeframe does not allow for quick growth anyway, the overall result will be quite realistic. And besides, what is to say there won't be, somewhere in the game, a gifted pop growth administrator amongst AI governors? Most of the AI has fertility temples too...

(not sure if my point is clear?)

[Quinn Inuit]

That would be a reasonable plan if these were just human players, but the AI would fail miserably at that. I want to keep it just at the buildings--the AI will have enough trouble with those as-is. It's as unrealistic to have too few huge cities as it is to have too many.

[Metaluis90]

TL;DR





jk, there's heavy maths applied there... something I proudly left alone a lot ago

[Quinn Inuit]

Yeah, this is one of those inside baseball threads. I post them here in case anyone's curious besides the mod team.

[Boom S]

I am, so you have one reader at least !

[Juan_de_Marco]

Yes it has been very enlightening, I had a hunch when playing, but never got around to break it down into a formula. Thanks for that at least.

re: AI; I understand that, but I disagree where you say it is unrealistic. In fact when looking at the 'what farming levels should the be in which province' thread, it can be considered more realistic -I mean historically- to have really few Huge cities. You may be right if you mean that it could potentially become unplayable with the AI not using it as well as a human player. I meant to say too that the AI usually (okay, not always) puts squalor reducing or agriculturalist generals in place as governors as well, -for reasons of public order AND income- negating their perceived disability to grow cities over the threshold. If it would be possible to set the AI to a higher 'enslave when conquered' percentage (is too few in 3.5.3 in my opinion), cities in the heartland of every nation have a realistic potential to become huge. I'm willing to playtest it if somebody can hand me the code.

edit: Anyway, just pleading the case here :p Hope its convincing.