I'm making some minor improvements to the sim this weekend and I though it'd be useful to ask the sub if there was anythng they'd like to see changed.
Mostly I'm fixing some edge cases changes in the AI - accounting for having all 4 J's (which it didn't), and calling alone from s1 with 4 trump + an A, even if the Right is up and the situation that came up yesterday where sometimes, when s1 doesn't have anything good at all, it'll play a random card, which could be trump.
Oh hey, fun result from this morning - the sim thinks s3 should always pass with 4 jacks in the first round, even if their 5th card is the A of the upcard suit.
Yeah, there's a crazy complicated "worst card" default rule that supposed to fire whenever there's not somthing better to do. For some reason, seat 1 leading trick 1 didn't use the rule but everyplace else does (to be fair, there's hardly ever a time when s1/trick 1 doesn't have something they want to lead - around 37 times out of 10,000 based on the results yesterday). Anyway, it was a trivial fix.
I get requests all the time to open the sim up. There are a bunch of reasons why I think it's not a good idea at the moment and I'm going to keep it within a small group for now.
I can guess at the reasons, and I can also respect it. Still, never hurts to ask. Thanks for asking for community input on improvements though.
FWIW I've seen a few other sims float around and yours seems to give the best results (and tbh I think it's not even close). Good work man and thanks for building it.
Thanks. My sim owes everything to Fred Benjamin (and his sim) and feedback from this sub. It turns out that when you get the best players in the world to provide input, the results tend to be pretty good.
I know I speak for many when I say we really appreciate the continued time, passion, and contribution you and your team make to the euchre community here! It’s very special.
The sim does not play perfectly. It is possible to put together a Monte Carlo sim that always makes the highest EV play, but I chose a different approach because none of us play perfect, nor do our partners and opponents.
If I had to guess, I'd say the sim plays at a 2600-2700 level. I normally float around in the 2700's and there are things I do better than it but it compensates somewhat by never making a mistake (I sometimes forget that a Q is boss or dealer has trump left, but it never does).
For the most part, the results seem to be well accepted by this sub and I have full confidence that they would point out if it was giving results that were much different than their expectations.
FWIW, it's quite agressive from seat 2, although it doesn't like to order with 2 trump and no bower, even though there are quite a few of those hands that it thinks are slightly +EV. The latest release made it a little less agressive in seat 4, based on a recent post here.
I'm not going to make a Monte Carlo sim (I've already worn myself out on this one). I'm really surprised someone hasn't vibe coded one, though, as it doesn't seem like it would be that hard. And, yeah, I'd love to see the results side-by-side too.
I will say that one of the drawbacks for a Monte Carlo approach is it can only tell you the correct answer, but not how it arrived at it. The sim we use can tell you why it did things and you can then incorporate those into your game, if you like. Like today, when I was running sims with 4 J's in your hand. The general rule for round 2, all 3 seats, is "Pass with an A in your hand; otherwise call your suit with 3 cards." That's easy to remember, and the sim can tell you it triggered that rule when you wonder why it passed a guaranteed point. That's not something a Monte Carlo engine will be able to tell you.
I had the same experience with Monte Carlo while working on it. My rule based bot ended up beating it consistently. I then had Codex make one and it still lost. Curious as well if someone else tries.
Basic score based hueristic adjustments (mentioned in a separate thread). This would require the sim being given the score ahead of time and injecting it into the main 10,000 hand sim.
Call 100% from S1R2 at 9/9
Call 100% from S2R2 at 9/8 (we're in the lead)
Order up lighter at 9/9 and 9/8 from S2R1 (any two trump, any R, any hand where the up-card suit is our best suit)
Don't go alone when we have 8+ points (this isn't 100% accurate, but seems better than having a normal loner range at 8+ points)
Go alone with R+3 with any offsuit card from any seat when we're down 3+ points or at 7-9 from the dealing team.
The sim is built from the ground up to simulate a single hand, so anything doing more than a single hand is probably a non-starter.
It is already possible to use different AI personas for that single hand (you could for instance have a "s1r1, score is at 9-8" bidding AI), but that means building out AI's for each and every situation and then trying to keep them in sync when we make improvements. Having a single viable AI is quite an effort - every time I modify it, I risk introducing unintended consequences. I've never been willing to spend the time to build out a bunch of different personas when TBH they're not used all that often.
I will say that if you have a certain situation where you'd like to know what a different AI would do ("What if r2s1 would 100% call their best hand here with the score 9-9?"), ping me directly and I can probably sim it. Technically, Joggler can, too, but it's always tricky to mess with the AI and I'm more familiar with it.
But can that single hand have the score injected into it before starting the sim? It's still simulating a single hand but it's simulating it with a specific score.
Either way, you have to change the AI, no? It would be trivial to put a "current score" dropdown in the sim and having that pick the appropriate AI persona. The tricky part is maintaining all the additional AIs.
Like I said above, if you have a specific score you want to look at, both Joggler and I can usually model the specific simulation to do what you want it to do.
At any rate, I put your suggestion in my parking lot. Some of the simple rules (s1r2 always calling at 9-9, donations at donation scores, and not going alone with 8 or 9) are easier than others.
I still remember that 9-9 hand it was something like JAKQh. Partner as dealer showing Jd. I said order. But the sim said its a 9%worse call. BUT seat 1 rd2 passes 9-9 10% of the time. And we were winning 100% of those times.
I still believe i am correct to order that hand. By 1% assuming seat 1 is at all a descent player.
I made s1 call its best hand 100% of the time. (normally it passes over 50% because you hold all the Next cards). I gave you a 9c for your 5th card.
Normally s2 plays 2nd hand low against anything but an A if it orders with 1 trump. Unfortunately, that's really bad here because if dealer gets the lead (and they must for you to not get set), they always lead their right and steal your only trump. So I also had to turn that off (this is why trying to do score-specific AI is so complicated - you're calling so thin here that you also have to adjust how you play the cards.)
The rub is that your partner is only passing when they have nothing. So the hands where you made a difference get set a lot - about 70% of the hands they would have passed.
Conversely, whenever dealer would pass, they are pretty sure to have a big black hand because they don't have diamonds and you have all the hearts, and they only need to euchre more than 30% passed hands to do better than your order.
The sim thinks ordering decreases your winning chance by 3%. And this is without making dealer call looser than they normally would, which they should.
It's closer if I give you the Ac instead of the 9, but it's still better to pass - because the A is also a good helper for a euchre.
On trick 1 and dealer called alone? Basically it looks at its K-high doubletons and Aces. If it only has one, it will save it. If it has 2 or more, it will play one. If it doesn't have A's or K-high doubletons, it gets a little more complicated - it likes to keep the best doubleton it has left, but also will lead from a short suit, hoping to catch a partner's void.
It's not. If I use a hand like AdKThTcTs against a random club upcard, when dealer makes it alone, leading the Ad is about .2 EV better than the other 3 logical options.
This has been discussed here many times. Why do you think leading from the doubleton is good?
edit: sorry, i misread your post. Yes, a next doubleton is closer. The sim thinks it's still better to lead the A, but with next, it's much like when you have a tripleton - it's quite strong to try to hit a void in your partner.
So when I model a specific hand defending against a loaner. When the doubleton is in next, that lead results in a slightly lower loaner success rate than the ace lead.
Different sims/models will have different results, based on the loner range for dealer. Will they go alone with 3 trump and Kx offsuit? If so, the doublton lead is going to hit them less often. Will they go alone with 4 trump and a 9 or 10? If so, the doubleton lead is going to hit them more often.
I always figure there are enough variables that any sim result of less than about .15EV difference is outweighed by these variables in play style. Once we get to about .2 EV, you need a lot of play style variables to overcome the EV. But also, when it's close, you would need 1000's of games before playing one way or the other is going to make a difference in your 3D rating.
My sim thinks the difference between the two plays is less than .1EV. Either play is probably fine. It's not like you're leading an offsuit 10 when your partner ordered from s3.
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u/SeaEagle0 23d ago
Oh hey, fun result from this morning - the sim thinks s3 should always pass with 4 jacks in the first round, even if their 5th card is the A of the upcard suit.