Similarly, by having price volatility tied to quantity, not to players, it allows a single player to maintain the ability to have strong impacts on the game. A single player dumping steel can still crash the market. Scaling this by player risks no player being able to affect the market intentionally, and in that world what active things is any given player doing?
The way i understand the game, the companies are selling the produced resources to some market. In a 8p game, that market must be bigger than in a 2p or 4p game, there is double the number of production to supply it. A market 2 time bigger is 2 time less volatile to a fixed quantity of resources.
I'll admit that my two-sided market theory is a bit rusty, but I don't believe that this is actually true. By doubling the number of players, you double the number of firms involved in the market, but this doesn't BY ITSELF change market volatility. For instance, if you have a 4 player game of all Expansives, and an 8 player game of 4 Expansives and 4 Scavengers, the volatility of steel should be pretty close to the same as you've got the same number of firms generating supply and demand of said steel. (Admittedly one of the Scavenger players could go into steel if the prices were high enough, but I think you see my point.)
What DOES happen in an 8 player game is that the potential demand side on a number of resources goes way up. For instance, the total demand for power on the map definitely goes up from 4 to 8 players. But for other resources, market size is going to depend on HQ types. 8 Robotics will generate a game with less demand for water than 2 Scientifics will, despite one game having four times as many players.
Adding a modifier to price volatility that is based purely on number of players risks privileging players who are generating demand for under-demanded resources. The only non-Robotic player on the map may choose to forgo making food, and have a huge advantage in an 8 player game vs a 4 player game as the price of food will go up more slowly in one game over the other. I think it's much cleaner, more understandable, AND more balanced to modify price directly in response to actual supply (sales) and demand (buys).
(Another quick example: even if a resource were in equal demand in all situations, reducing price volatility in an 8 player game makes early stockpiling of that resource cheaper. Making up some numbers, if there is a 4-player game where buying 100 glass costs $5000, and doing so raises the price of glass so that buying a second 100 glass costs $7000, but the numbers in an 8-player game are $5000 to $6000 instead, buying up a bunch of glass in the early game becomes a better strategy in games with more players. I'd much rather see strategies be better or worse based on map conditions and other players' decisions rather than just "there are this many players".)
I still don't understand why this is desirable. I'd be strongly worried that it provides perverse incentives to build primarily advanced buildings and and just buy raw materials from the market. For instance, if buying water from the market has a reduced impact over doing the same with food, then wouldn't it just be smarter for me to build a triangle of farms (getting up to a 1-to-1 conversion efficiency) and buying water from the market? After all, food is now a privileged commodity within the market's demand algorithm, so in theory I should pretty much always be making a relative profit this way (as the reduced volatility of water should tend to keep its price depressed below that of food).
You are right on this, it would be an efficient abuse. The main problem here is the inability to run out of water.
I don't want to repeat myself too much, but i still think having a market stockpile would completely regulate the market and prevent any of those abuse. More than any artificial algorithm could.
I don't know that I'm absolutely against a stockpile, but two questions:
1. Does this do anything other than provide a hard limit on how much someone can buy of a resources (rather than a soft limit based on rising prices)?
2. What happens if the stockpile is empty? Can you not buy the fuel you need? Do your blimps all stop? Do you suddenly find yourself unable to make any money because you can't get your resources delivered? Are you stuck forever? I think that a purely theoretical market where supply is infinite makes the game much cleaner to play.