# Can I still trade 4:1 with the bank if I own any 3:1 or 2:1 port(s) just to get rid of more cards?

Even if I have a more favourable trade with the bank, can I still do a 4:1 trade to get rid more excess resources (e.g. to avoid the robber)?

• That's next level tech right there. – corsiKa Feb 3 '17 at 20:00

## 2 Answers

Based on my read of the rules, specifically the section in the Almanac on Maritime Trade, I don't see any reason why you couldn't trade at the 4:1 rate even when you have a better rate available. I even see this text:

Generic Harbor (3:1): Here you may exchange 3 identical resource cards for 1 other resource card during your trade phase.

The use of the word "may" makes me think it's optional. If they wanted you to only be able to trade 3:1 after getting a port, they probably would have used stronger language.

• Seems like the important part would be the sentence that says (emphasis added) "During your turn, you can always trade at 4:1 ..." – Tanner Swett Feb 4 '17 at 16:55

I agree with Ben's assessment that you could, but I am pretty sure you don't want to.

Anecdotally, I've played a lot of Settlers and never even considered this move (20 years and something new!). Compress to avoid the robber, yes. Compress at a worse than optimal ratio to avoid the robber, no.

The probability of the robber happening before your next opportunity to spend your resources is:

1. 1-(30/36)^3 = 42% (3 player)
2. 1-(30/36)^4 = 52% (4 player)
3. 1-(30/36)^5 = 60% (5 player)
4. 1-(30/36)^6 = 67% (6 player)

But that's not the whole story.
You'll be drawing more resources depending on the dice rolls.
You'll be trading with other people, sometimes card for card but sometimes effectively compressing or expanding.
In 5 & 6 player games you have the intra-turn exact-spend opportunity which you might be able to take advantage of.

With all of that it's very murky whether compressing less than optimally (instead of compressing optimally) delivers more benefit (sometimes avoiding the robber) than cost (compressing away extra cards).

Edit: Intra, not inter. No english points for me today.

• It may be optimal strategy for an edge case. Suppose I need to get rid of 3 cards to avoid the robber. Trading 4:1 and getting back one leaves me in a good spot. If I needed to get rid of 3 cards and trading 2:1 or 3:1 may require giving up a card I don't need. Though I suppose I could always trade 4 of one resource for 1 of the same resource. Hrmm... – Freiheit Feb 3 '17 at 22:14
• It could also be helpful to the flow of the game. Making one trade at 4:1 versus two or three trades at a better ratio might just take less time and keep the game moving. – Freiheit Feb 3 '17 at 22:14
• @Freiheit, If the odds are higher that you'll get resources instead of the robber on the next roll (and they usually are), you'd be better off not trading at all. Especially since you appear to be in a scenario where getting one kind of resource is easy for you. – ikegami Feb 4 '17 at 4:58
• I've used this tactic in a few trades myself. Let's say I have enough in my hand for a city upgrade, but I'm 1 or 2 cards over the top. I sneak into my trades one extra card (someone wants wood for brick? I'll give you a brick and 1 cattle for wood). The players would accept, thinking to themselves "I'd have taken just the brick" when in fact I'm just securing my next investment. I rather lose the extra card for the certainty I'll get to do the upgrade, instead of the chance of having to throw away half of my cards and lose the chance to do the upgrade. – CyberClaw Feb 6 '17 at 10:19
• The chance is always there. It's unavoidable. If you play under 7 cards, you are avoiding the chance altogether. It moves the game towards strategy and makes it less reliant on lucky/unlucky rolls, which IMO is invaluable. – CyberClaw Feb 6 '17 at 10:23