Trading luxuries: good idea?

[AeonOfTime]

I haven't found any threads on this topic, and as it's been an issue in quite a few of my games, I thought i'd share my experiences, which led me to the conclusion that trading luxuries and resources is NOT a good idea.

I'm more of a pacifist builder myself, and try to get along with pretty much everyone else. However, keeping the other civs at bay is not that simple. You have to keep them satisfied by trading techs, resources, luxuries.... you name it.

The big disadvantage being, that supplying your "enemies" (which they can become very quickly if they think they are powerful enough) with luxuries and resources doesn't benefit yourself as much as it benefits THEM.

Example: in a recent game I played, I traded the babylonians dyes for a World Map, 5 Gold per turn and 20 Gold. As they did not have so many luxuries, the dyes I gave them enabed them to put more workers in the field (at least in cities with a marketplace), and get an overall production/research boost. ...That's in absolutely no relation to what they were willing to give (and they had 500 Gold in store and a few interesting techs).

Of course, this also has to do with the difficulty setting (I'm playing on Monarch), but I think this makes trading luxuries and resources pretty useless. You're better off keeping everything to yourself.

How do you handle this? Or was this never an issue?

AeonOfTime

[cumi]

Hi,

trading luxuries and strategic resources is very imporant issue for me. If you have more than one tiles of luxuries of one kind it is very useful to sell it, for example in exchange for a luxury, that you don't have. I suppose, you can controll NOT MORE than 3 types of luxuries.

Without buying luxuries how do you think, to make your citisens happy?

Selling the luxuries for gpt, you can also get nice amount of money and you can get FRIENDS. This can be an important issue if you are pulled into war...

[Cruddy]

Hmm... If you don't trade, the AI Civs get very annoyed. Trading partners are less likely to be seen as potential threats, although this is only true up to a point (militaristic neighbours with overwhelming numerical superiority - yikes! You're screwed either way).

On balance, I think going for the trade is the best option. Excess luxuries do you NO GOOD AT ALL. Even if it's just one lousy gold and a map you already have, that's more than you would have without the trade.

Of course the AI will stitch you up on trades, but HAGGLE. Your trade advisor will say whether it's acceptable or not You can only really expect to get obsolete techs for luxuries - no one is going to tell you how to build a Great Wonder before they've had a chance to build it themselves!

One final point - the AI will get dependant on a luxury you have been trading. So every 20 turns, you can keep raising the price (always assuming the attitude is cautious or better... annoyed rivals will sometimes just refuse to trade at all).

[Cort Haus]

On the whole, it's good to trade, but not every trade is good.

Cruddy : Getting 1g is worse than nothing if you give the opponent 20g or 100g or 1000g worth of extra production, and you want to keep them down - but I don't always want to keep opponents down - I support my alllies against my enemies, and want my allies to be strong to stop my enemy from trashing them. I'd rather give resources for improved relations than sell for a single peanut.

AeonofTime : You have a point that the enemy can benefit more than you, so that's a case-by-case decision per civ per trade and not a matter of global policy when playing civ. So your conclusion is mistaken - you might instead conclude that there are occasions when a trade is not worth it.

Cumi : There are many ways to get people happy without buying luxuries : The luxury slider, happy-buildings, entertainers, military police - and getting lux thru tech-trades, extortion.

[Solver]

Indeed, it's good to trade. This keeps the AI quite happy with you, and a country that has two luxuries and Horses coming from you will probably think twice before attacking you - why attack if they know they're going to lose it all?

Also, sometimes you get very good gpt deals and they're worth it... and as already pointed out, extra luxuries do you no good. Sometimes, if I want a MPP and the other civ doesn't, a luxury added is what makes them happy.

[DAVOUT]

I am much more concerned by trading techs than by trading luxuries; as it has been said, we can stop every 20 turns a trade of luxury whereas a tech deal is for the whole game. I am particularly cautious when my civ is commercial. I have observed that a commercial civ has a potential gold production big enough to finance the research and get ahead of the pack before Feudalism on its own. I appears that the gold NOT given to the AIs reduces considerably their rythm of discoveries (this is at Regent).

[Catt]

I wouldn't hesitate to trade luxuries to the AI civs -- I just can't see how they get a tremendous benefit from it. For one thing, except to combat war weariness, the AI never uses the luxury slider, so trading luxuries won't allow them to decrease the slider and preserve a lot of extra income. Additional luxuries will let the AI put some entertainers back to work in cities -- but I've got to believe that in most cases the extra shields help only at the margins (since production is rounded at the city level and excess shields are lost) -- which really means that the AI is getting a little extra gold from what would otherwise be extra entertainers. Depending of course on what you can get for your luxury (and how much you value the mere existence of a trade deal), I wouldn't be overly concerned about trading luxuries.

Strategic resources call for a bit more caution, but again I don't worry about it too much, even in those cases where I'm not trying to support the weak and deny the strong (i.e., as Cort Haus mentioned). Is my neighbor an extremely aggressive civ that has no iron? Ok, maybe I won't trade that extra iron to that particular civ. But even with an aggressive neighbor, unless the overall strategic situation (map features, strength of empires, technological development, known unit counts, etc.) implies that I could conceivably have a real fight on my hands if my neighbor had iron, and assuming the neighbor has something interesting to trade, I'd probably feel free to trade it without much fear. Even if the neighbor is emboldened by a few new swords or knights so far as to threaten me, it really would just provide an opportunity to do some pruning

Catt

[Cruddy]

Originally posted by Cort Haus
On the whole, it's good to trade, but not every trade is good.

Cruddy : Getting 1g is worse than nothing if you give the opponent 20g or 100g or 1000g worth of extra production, and you want to keep them down - but I don't always want to keep opponents down - I support my alllies against my enemies, and want my allies to be strong to stop my enemy from trashing them. I'd rather give resources for improved relations than sell for a single peanut.

I admit, that was a bad example. A trade for 1gp can build up to a worthwhile arrangement later - but it's only usually worth it to keep a massive empire from ripping across your territory to rape it.

[dexters]

Interesting thread.

I need to ask clarificaiton about how an extra luxury would allow AI civs to produce extra workers.

Are you talking about rush building using pop and trying to keep their resentment down?


Anyways, I have a tendency to try an monopolize as many luxuries as I can get my hands on. This is advantageous no matter where you are. If you're ahead, well... luxuries become another tool you can use to manage the world to your liking. If you're about even, pulling a luxury from a rival just as they go into war against you or someone else could affect them. Or if you're behind, the cash and the goodwill luxuries generate will give you an advantage in making powerful friends, or at least buy you some time.

Monopoly is key here. If you do not have monopoly, there is some civ out there who is not trading with you and could declare war without worrying about it.
There are of course nice diplomatic things you can do to make things more complicated if you don't have monopoly, but luxuries tend to cluster. Strategic resources don't. It's usually difficult to even come close to monopolizing those trades.

EDIT: Someone mentioned the AI doesn't use the happiness slider. Is this confirmed? If so, what is the detault? 0?

[Solver]

Strategic resources call for a bit more caution, but again I don't worry about it too much, even in those cases where I'm not trying to support the weak and deny the strong (i.e., as Cort Haus mentioned). Is my neighbor an extremely aggressive civ that has no iron? Ok, maybe I won't trade that extra iron to that particular civ. But even with an aggressive neighbor, unless the overall strategic situation (map features, strength of empires, technological development, known unit counts, etc.) implies that I could conceivably have a real fight on my hands if my neighbor had iron, and assuming the neighbor has something interesting to trade, I'd probably feel free to trade it without much fear.

Hmm, I just can't help but prepare for an invasion of civ without Iron. If they got no Iron, it's no Swordsman counterattack, and I want their land before they become a thread. Sometimes I may wait till Middle Ages, though, where Knights vs. Spearmen is a joke.

[Cort Haus]

Originally posted by DAVOUT
I am much more concerned by trading techs than by trading luxuries; ....

Tech trading is another subject. I think this thread is specifically looking at luxury trading, though'd I'd say that selling techs is generally preferable to buying them, depending on circumstances. However, that doesn't stop many players happily buying tech as policy in the ancient era without long-term problems.

[Catt]

Originally posted by dexters
I need to ask clarificaiton about how an extra luxury would allow AI civs to produce extra workers.

I interpreted the original reference to "workers" to mean city laborers, not actual worker units.

EDIT: Someone mentioned the AI doesn't use the happiness slider. Is this confirmed? If so, what is the detault? 0?

That was me, and yes the default is 0% luxury spending. Soren Johnson wrote in another thread:

Originally posted by Soren Johnson of Firaxis
the luxury slider is very, very tricky. the AI basically only uses it to balance out war weariness, and there is a maximum level it will never go over. the danger was that the AI could get used to the luxury slider and deemphasize acquiring luxury goods and building happiness improvements, allowing a good portion of the treasury to disappear.

The full thread is HERE. Another great thread for AI behavioral answers (with Soren's participation) is alexman's Why, of why does the poor AI ... thread -- be forewarned however that specific examples of inefficient AI behaviors have since been addressed (due largely to that thread!).

Catt

[Cort Haus]

I was away from Civ and Poly for a while, so I missed the forum's discussions on PTW - thanks for posting that link. Off-hand, does anyone recall any other PTW-strat/AI threads worth a look? Especially later ones, as this has more initial reactions.


(typo edited)

[dexters]

Catt, appreciate the link to that very interesting thread.

A question, how can I access the game's debug mode?

[Nor Me]

Originally posted by dexters
A question, how can I access the game's debug mode?

Ypu need to use a scenario. There's a tick box under scemario properties in the editor.

[Nor Me]

On topic, since the AI normally pays almost half a gold per turn per happy face for the luxuries you sell them, it's almost always going to be worth it.
I only wouldn't if I were tying to maintain a balance of power between AIs.

In any case, a lot of the time what's good for an individual AI is good for me.

[dexters]

I'm not sure if Soren is still around but it's worth mentioning anyways.

On the issue of luxury slider, the concern was that the AI could get used to it and not trade for other luxuries. I wonder if it would be possible to build in a calculation routine that would sold this- an incremental "shadow price" analysis.

When luxury trades are available with other AI or human players and the AI is using the slider, it simply compares the relative worth of both options and goes for the cheaper one.

ie: If obtaining a luxury would net 100 happy faces for the entire civilization and it will cost the AI 500 gold (This is assuming it convert tech trades into a gold value) then you have 200/100 or a ratio rating of 2. Or it costs 2 gold for 1 happy face.

The AI then compares it to its current status. If luxury slider > 0 then it attempts to decrease the slider by one increment. The happy face reduced would constitute the "shadow" or incremental price. Let's say that by reducing the slider by 10%, the AI loses 90 happy faces in all of its cities but gains 230 gold. 230/90 = 2.56 or it costs the AI nearly 60% more to keep its luxury slider at its current level. The optimal strategy would be for it to lower its slider increment and attempt to obtain the luxury.

There are constraints of course. The AI may simply not be able to afford the luxury, in which case, maintaining the luxury slider would be the optimal option for the AI. But I'm assuming Soren's concern was that it would avoided trading even when it can afford it.

I can see a key objection that could be raised

--This method may cause the AI to dumbly go for the cheapest happy faces disregarding effect. For example. It may cost the AI 2 gold to obtain 1 happy face. But it may only have a net gain of 50 faces. On the otherhand, the AI would gain 60 happy faces at a cost of 3 gold per face if it were to set the slider up by one increment.

The optimal strategy here is not clear. The AI may need 60 happy faces to keep all cities out of revolt or in WLTKD. So while it may obtain the 50 happy faces through trade is cheaper, it loses 10 happy face and opportunity gold in lost income from revolts and WLTKD.

There are various solutions that I can see

1) The shadow price calculation can be extended to measure the net effect of losing happy faces. If I loose 60 happy faces by reducing luxury slider by 1 increment and gain 50 happy faces by trading, what is my net gain?

Well, perhaps the AI may have a net gain in income of 30 gpt. It then multiplies the 30 by 20 turns (the life of the luxury trade) = 600 . This amount is then deduced by the net loses. 10 happy face lost. How many cities will go into revolt or loses WLTKD? Calculations here could get tricky, and I don't pretend to know how to solve this efficiently. But Soren might.

2) An alternative would be a far simpler method used in linear programming and goal programming. Simply constrain the decision.

I'm assuming the AI will always know how many happy faces and content faces it needs to keep "status quo" level of production. I say "status quo" because I am also assuming there are already behavioural constraints in place to prevent the AI from doing something really strange when it has only "maximize X or Y" to go by-- like reducing research to 0 because it has to maximize gpt income. By default then, status quo is suboptimal for the individual dimensions (gold income, production, food) but is hopefully optimal taken as a whole.

The AI could then constrain its decisions. Even if it is cheaper to obtain happy faces through a luxury, if it fails to generate enough happy faces, the decision is rejected. Perhaps an algorithim could be put in place where the AI can mix and match trades. Perhaps there are two luxuries avaible? or 3? If may try to obtain all three, calculate an AVERAGE COST for each happy face generated and compare it to the current "status quo".


Thoughts?

[dexters]

I wan to add a clarification.

The "status quo" I talk about assumes the current state is the "best" or "preferred" state for the AI. This may not be the case. War weariness may have set in for the AI civ and the current "status quo" is infact not as good as the previous state.

Again, I don't know how the AI makes its decisions when it comes to maintaining happiness, but I can only assume that it has a goal, either hardwired or based on some formula running in the background. In that case, the status quo would be the initial happiness goal the AI civ has set for itself and not the current state of the Civ.

[AeonOfTime]

I'd like to add a clarification too:

I'm playing mostly builder games, so this will probably not apply that much to the warmongers among you...

I usually go for all happiness wonders as a priority (Sistine chapel, J.S.Bach...), which give you an overall production boost in the sense that you have less unhappy people and need to play less with entertainers or the luxury slider.

The AI then only has luxuries and the standard buildings left to fight against unhappiness - not really very effective. In this case, trading luxuries can be a HUGE benefit for them, depending on whether they have built a marketplace in their cities:

Without a marketplace:
Each luxury gives you 1 happy face. This means that even in each city without a marketplace, 1 (if any) unhappy citizen will become content, and start producing if there are city tiles left to work on.

With a marketplace:
It works like this: (first number is the amount of luxuries you have, the second the amount of happy faces you get for that luxury, and the total happy faces)
1 => 1 => 1
2 => 1 => 2
3 => 2 => 4
4 => 2 => 6
5 => 3 => 9
6 => 3 => 12
7 => 4 => 16
...

So let's say you're dealing with a civ that has two luxuries in its luxury box (use diplomaxy / spies to find out how many they have), trading them a third will give them 2 more happy faces in every city with a markeptlace, and 1 more in all others.

That's more than even wonders can do... And it gives a whole new dimension to trade embargoes.

My point in this was originally that for what the other civ gets, you only get peanuts. And hagling doesn't really take you very far at all.

(Cort Haus)
You have a point that the enemy can benefit more than you, so that's a case-by-case decision per civ per trade and not a matter of global policy when playing civ. So your conclusion is mistaken - you might instead conclude that there are occasions when a trade is not worth it.

I agree - but when I'm willing to trade, I'd like to get a little more out of it. I usually only do it to keep the other civs happy, but it doesn't really make me any richer... at some point, you've just had your fill of world map trades.

[Nor Me]

Originally posted by AeonOfTime
My point in this was originally that for what the other civ gets, you only get peanuts. And hagling doesn't really take you very far at all.

This need not be true. As I've said before if the AI has the cash, it will pay almost 10 gold per happy face in a 20 turn luxury deal. I know because I've tested it:Partial and pointless formulae: resource cost

In a city where the happiness is needed, the AI can put entertainers to work at a cost of 2 happy faces per tile (Although an entertainer only produces 1 happy face, they're naturally content whereas another labourer would be born unhappy.)

So the AI is paying you almost 1 gold per turn per tile .worked where the happiness is needed.

Generally, unhappy cities will have less improvements often because they are more corrupt. Uncorrupt cities with marketplaces are likely to already be happy.

Suppose for instance that an AI empire has equal numbers of core and fringe cities, that the core cities have marketplaces and cathedrals and so are not unhappy and fringe cities are all unhappy and have no marketplaces. Suppose they already have 3 luxuries and you can trade them 2.

For each extra tile worked in a fringe city, the AI is paying you 1 gold per turn for the 2 extra happy faces in the fringe city and 2.5 gpt for 5 unnecessary unhappy faces in the core city.

If the tile is reasonably good, it will produce 2 food, 2 production and 2 commerce. No more settlers are needed at this stage and if the city gets bigger, there will just need entertainers so the food is almost irrelevant. The fringe city is corrupt and has few improvements. Let's say it's only 25% corrupt, has a library but not a university ( I've already said it doesn't have a marketplace.) and certainly doesn't have a factory. Let's say 50% tax and 50% science.

Then for each slightly under 3.5 gold you gain, the AI gets 1.5 production, 1.125 beakers and 0.75 gold. If all these were worth 1 gold, then the AI is actually losing out!

This model is a bit extreme but even in a reasonable situation, you should be able to get more than peanuts. Even if you're only getting a quarter of what they're getting, if there were more than 4 AIs or this civ was less of a competitor than average or even that you could make better use of the gold then it would be worth it.

[kmad]

The AIs will be more reluctant to trade luxuries with you depending on the more Marketplaces Banks and Stock Exchanges you have in your cities.. usually I only bother trading luxury for luxury when I'm playing against other human players

[AeonOfTime]

Originally posted by Nor Me


I know because I've tested it:Partial and pointless formulae: resource cost

Thanks, Nor Me - that clarifies thing quite a bit (although it took me some time to get into your writing style ).

Then for each slightly under 3.5 gold you gain, the AI gets 1.5 production, 1.125 beakers and 0.75 gold. If all these were worth 1 gold, then the AI is actually losing out!

Oh - then I was way off the mark from what I thought they owed me for what I was willing to give. I guess I'll have to review my trading expectations just a little

Thanks a lot for the great info!