AI valuation of techs

[Outlandish]

I traded away music today while building Sistines for failgold. It made me wonder, does the AI consider whether or not a wonder associated with a tech has already been built?

i.e. Would I get more gold selling music before I built Sistine than after, assuming it was known by the same number of AIs and the AI didn't start researching it and whatever else could reduce it's value? If so it might behoove me to trade it just before I finished a wonder I wanted rather than after. Conversely, do I pay more for a tech whose wonder is still available?

I'm assuming there's no difference, but I know if I'm playing an IND leader with marble or I have a GE sitting around I'd happily pay extra for Lit if GL hadn't been built yet for example.

 

[coanda]

Unlike the AI tech research algorithm, which is pretty lengthy in which factors it considers, CvTeamAI::AI_techTradeVal is brain-dead simple.

Take the beaker cost remaining if they researched it themselves. Multiply by between 1.5 and 2, depending on how many other civilizations know that tech. Potentially multiply by 1.1, for some specific techs that the AI is hard-coded to value 10% more highly in trades (such as Archery). And... that's it. That's how valuable they think the tech is.

Then they usually insist on at least a 10% profit on the trade overall, in their opinion. If they think your side of the table is worth less than 110% of their side, they generally won't agree. And there's a bunch of reasons they might refuse to buy a tech from you that have nothing to do with perceived *value* of the trade (e.g., if you are their worst enemy).