View Full Version : how do AIs value techs in market?

Aug 15, 2005, 03:43 PM
There are great articles telling us how do AIs determine which tech to research next and how much would it cost. Well, which one determines a tech's value when you want to exchange it? For example, at sid level, standard map, 8 civs alive, 1st hand nationalism costs 7200 gold to research, and steam power costs the same 7200 gold. But I'm pretty sure that with nationalism you will get steam power and a lot more. On the other hand, AI goes for bronze working in the very beginning almost for sure, but they won't spend much for it in exchange (you can't get wheel or masonry or alphabet by selling them bronze working, can you?). So what's the answer? Thank you!

Aug 15, 2005, 04:04 PM
Im thinking it has to do with the amount of beakers it takes to make wether or not they get anything from it UU etc, Dead end tech or not, Needed for next age, wheter or not they like you, and on higher difficulties I believe they will make cheap deals with AI and more expensive deals with you.

Aug 15, 2005, 11:12 PM
The things that make the AI value techs more include enables government, drafting, or mobilization (the latter two show why nationalism is so highly valued). In addition, the more people that know a tech (particularly if it's a monopoly) will affect the price. Optional techs are worth less. Whether a wonder has been built will also affect the price of its enabling tech (or was this changed in Conquests?).

Aug 15, 2005, 11:14 PM
I think the wonders still affect it, because after Bach's is built you can't get more than 10-12 gold for Music Theory.

Aug 18, 2005, 09:09 AM
The fact that a wonder is built or not is changing too few the price, something like 5%. So if a civ gives 10g for it this means it is researching it and it's due next turn.
Actually all the tech prices start at the base price in the editor that can be changed. Than you apply the modifiers. Is it optionnal - 2/3 of the price. Government, drafting, mobilization, double worker speed - double price (not sure for the latter).
The number of civs knowing it changes things too. Important to notice, the number of known civs. That's why exploration is so important, this brings the suicidal galley strategy. If you know all the civs but they dont know each other, you'll always sell at monopoly - the highest price possible.
If you already have some beakers invested in a tech, it's cheaper.
I think someone came out with a formula of this (used in CivAssist2), but don't recall it now. Or was it on the research prices??? :confused:

Aug 18, 2005, 11:42 AM
I think someone came out with a formula of this (used in CivAssist2), but don't recall it now. Or was it on the research prices??? :confused:
That was the research price (computed a long time ago IIRC). As far as I know a formula to determine the trade value has not been computed.

Aug 19, 2005, 07:50 PM
There are 3 kinds of prices: research cost (number of beakers), research value (to determine which tech to research next), and trade value (how much AI would be willing to pay). There are already excellent posts about the former two. But I still don't fully understand the 3rd. For example, AI will pay dearly for nationalism, but little for bronze working, but both of them are the 1st choice of that time (research value) and cost more or less the same with other techs (research cost). This is very strange to me.

Aug 19, 2005, 08:04 PM
Maybe it has something to do with what techs they ALLOW to be researched - Nationalism allows 2 governments and another tech, BW only allows IW. Perhaps some tests are in order, this might be a good place to start.

Aug 25, 2005, 10:34 PM
Another example is feudalism. Its research cost is lower than engineering and monotheism, but its market value is much higher than those two. This is same as nationlism, but why bronze working is not so magical?