demand propagation along railroads

[Alfed E Neumann]

Sometimes, demand will propagate by rail.

If you can't make sense of the above sentence, I'll try to explain a bit: at station A, there's a sawmill; at station B there is none. Sometimes, station B will become aware of the demand at the other end of the line and increase the price it bids for timber, becoming the center of a local maximum. The price may vary, but it's always lower than at station A so that the goods can still be hauled at a profit.

This can be helpful, as it funnels the goods towards station B where they can be picked up in bulk; it's certainly convient if you no longer have to snatch the wares from a passing stream, sparing you all the hassles of dedicated trains waiting for custom consists. On the other hand, it cuts into your freight rate.

However, wether or not this happens seems to be rather erratic. I usually employ a hub-and-spoke scheme and frequently see that demand at the hub propagates to some, but not all spokes. If there's any system behind it, I fail to notice. What can I do in order to force or avoid this?

[Gwizz]

I can't say why the supply and demand system works the way it does.

I get around it by routing the train to a demand station then after the train starts I reroute it to where I want to send the cargo. I seem to be able to make a profit doing this. If more or less I can't say.

[thegrindre]

Welcome to the forum, Al.

Enjoy yourself and happy holidays to ya.

[Alfed E Neumann]

Hello again.

I've been watching this closely, and here's what I found out so far. There's probably more to it, and/or I may have gotten something wrong. But anyway:

- there has to be an actual train running the route. The current station may only inherit demand from the next station on the train's route.

- there may be no supply of the ware in question within range of the current station. The logic seems to be that if the ware is available anyway, increasing the local price would merely spoil the freight rate. But even if there is a producer, or a large strem of the ware flowing through the stations' sphere of influence, the price may be updated provided the ware is momentarily sold out. Trifle amounts don't matter, though -- I've seen a station increase the price for iron repeatedly although 0.3 cartloads were still sitting there. If there's not enough to justify a cart, this apparantly counts as "unavailable".

- Probably the train has to have unused capacity in order to update any prices. But I'm not entirely sure of this.

- There's obviously some chance involved: a station will not update the prices for all wares everytime a train stops there. It also seems that the chance isn't equal for all cargoes. In my current game,
-- demand for iron and aluminum spreads like wildfire.
-- timber, goods and all sorts of foodstuff propagate reasonably well.
-- bauxite and paper didn't receive any updates at all, in more than 20 years.

- custom consists don't seem to work: as it seems, you cannot specifically request any ware.

[KevinL]

This writeup on GameFAQs explains the supply and demand system fairly well:

http://www.gamefaqs.com/computer/doswin ... 4361/49084

I found that FAQ first, which really helped me. Then I found this forum and I learned even more.

[Zoogz]

This writeup on GameFAQs explains the supply and demand system fairly well:

http://www.gamefaqs.com/computer/doswin ... 4361/49084

I found that FAQ first, which really helped me. Then I found this forum and I learned even more.

Thanks for the kind words, though I intended the FAQ to be a top-level overview rather than a nuts-and-bolts look at the actual programming. I would be extremely interested to see if Al E. can come up with more information on this topic; I can think of very little information more useful to a tycoon than the future knowledge of prices.

While thinking about possible economics-related causes, I came up with the following scenarios:

1) Global supply. If there are 100.0 units of paper cumulatively at twenty different stations, that's a stable supply that isn't being used and therefore the price should be pretty stationary. If there are only 15.0 units of iron cumulatively at the same twenty stations, I would certainly make the assumption that demand would push the price up.

2) Pull-through supply. If the demand for goods is extremely lucrative, I would think that aluminum would rise in price, being a precursor material. Additionally, if there are numerous steel mills on the map all bidding for a resource (iron) I would also assume that the price would rise. (Maybe check the ports too?)

3) Development. It is a long shot, but maybe the price of iron could be going up due to excessive steel usage in the form of... building track?

My personal reflection in this matter was one of the attempts I made playing Orient Express. For one game, the entire countryside of Austria demanded alcohol at +$30 to +$40 prices. If I knew how I could get those numbers to translate to higher prices at my station (and therefore higher prices at my factories), I would have had far more financial success. As it is, I should have just transported the alcohol rather than spent the money investing in (multiple) factories.

Be sure to tell us if your research bears fruit, Al E., and good luck!

---S. "Zoogz" Jamison

[Alfed E Neumann]

If I knew how I could get those numbers to translate to higher prices at my station (and therefore higher prices at my factories), I would have had far more financial success.

At the risk of preaching to the choir: you're aware that the freight rate simply is the price difference between the two stations? So, raising the price may increase the industry profit, but it will cut into your freight rates. I've never looked that closely, but presume that in the end you'll come out about equal.

In the case of alcohol, though, creating demand is simple even withough any demand propagation magic. Trains loading alcohol will happily collect it from people's homes (I always try to imagine them doing it). Homes without booze? That means demand. Usually, regular shipments will suffice to normalize the prices within 12-18 months.

Real trouble can be expected if the receiving station will get multiple large shipments within a short timeframe. If you're afraid of that, you may want to use a sponge: a train waiting for cargo in the supplying station, soaking up the surplus. Destroying that train, cargo and all, is often better than allowing a large supply of any good to suddenly spill into an unexpecting market.

Of course, this approach works just as well for any other consumer good.

[Hawk]

This writeup on GameFAQs explains the supply and demand system fairly well:

http://www.gamefaqs.com/computer/doswin ... 4361/49084

I found that FAQ first, which really helped me. Then I found this forum and I learned even more.

Which is also now available for reading right here on the main RRT3 page, with permission of course.
Thank you Scott.

[Zoogz]

If I knew how I could get those numbers to translate to higher prices at my station (and therefore higher prices at my factories), I would have had far more financial success.

At the risk of preaching to the choir: you're aware that the freight rate simply is the price difference between the two stations? So, raising the price may increase the industry profit, but it will cut into your freight rates. I've never looked that closely, but presume that in the end you'll come out about equal.

Which is exactly what I *wanted* to happen. I wanted the high prices at my home station(s) so that my factory(s) would net more money without the necessity of having to purchase more trains and putting more congestion on my track. See, if I didn't own those factories, I would have been completely content to cash in on the freight rate, as that's the only profit I'm going to make... but when I own the factories, I want prices to be high at the station so I don't have to spend the fuel and engine cost looking for new markets. I was never able to replicate that situation, either...

In the case of alcohol, though, creating demand is simple even withough any demand propagation magic. Trains loading alcohol will happily collect it from people's homes (I always try to imagine them doing it). Homes without booze? That means demand. Usually, regular shipments will suffice to normalize the prices within 12-18 months.

Real trouble can be expected if the receiving station will get multiple large shipments within a short timeframe. If you're afraid of that, you may want to use a sponge: a train waiting for cargo in the supplying station, soaking up the surplus. Destroying that train, cargo and all, is often better than allowing a large supply of any good to suddenly spill into an unexpecting market.

Of course, this approach works just as well for any other consumer good.

Thankfully, in the game in mention, the commodity was sourced from two or three stations and demanded at about fifteen, which helped profits... but again bugged me due to the number of trains I had to purchase in order to cash in the final freight rates rather than having the freight rates come back to the station for profit.

I've never tried the "sponge" method though... mostly because of possible future demands. If a far-flung station still has freight rates of +$10 for freight, which is almost useless to send to... having a 4.0 supply at a station can either show people how much they really need the freight which will hopefully lead to future demand, or the Tycoonatrons will end up shipping the freight to the location where it's demanded, which then tips me off to the next town to connect. (Of course, the freight demand numbers help too, but that can get a bit too micromanaging at times...)

[Alfed E Neumann]

Alright, I get the picture. I have to say, you're probably licked.

If you ever clicked on a home, you know that it will consume 0.03 loads of alcohol each year. So in order to keep a brewery busy, you need to distribute the booze to about 180 homes. When it comes to city sizes, one star equals about ten homes.

I just loaded the Orient Express map, at game start one brewery could probably provide enough beer for the whole of Austria. Okay, so cities will have grown by the time you own several breweries. Besides, much cargo will decay before reaching any destination -- still, distriuting booze so that a brewery will remain busy seems to be quite a bit of a challenge.

If your system is already congested as it is, the only hope would be to dump the stuff next to a river and let the tycoonatrons handle it. The danube ought to have quite some carrying capacity. Besides, more cargo moving overland will lead to more decay, supplementing actual consuption. As factory owner you don't care how or where the product disappears, so long as it's gone and makes place for next year's production.

Which brings me back to the sponge. I just made that up while writing the previous post, but coming to think about it -- you don't pay for the wares you load onto a train, do you? Sacrificing a cheap engine in order to make a million bucks worth of cargo disappear and boost future demand seems to be both a good investment and a mean exploit of game mechanics.

[KevinL]

Hey Zoogz, welcome to the forum.

This line from your FAQ is my favorite:

Most of our discussion
can also be applied to passenger and mail traffic, but just remember
that there's no processing of passengers - the game designers didn't
make a Soylent Green factory.

But you know, in the Editor we can make a warehouse or port that processes passengers into anything we want, like Soylent Green.