01-17-22 OE Monday - Trump in with the right #1

[Dlan]

The following are 3 hands in which the right was used to trump a trick early in the hand. This is the first time I've seen this used in our OE games.

Any thoughts?



https://worldofcardgames.com/#!replayer ... %3A1%7D%5D

[RedDuke]

I'm definitely a bit stunned that North trumped in against that ace in the first trick.

Normally, you don't want to play second-hand low against an ace. Second seat should take it. That only applies when the enemy made trump, though. When the dealer made trump, I'd throw off and let the maker take it.

[LeftyK]

this is why my #12 rule is don't play the right on offense like this. always over trump the ace or left of trumps or wait until trumps are led. playing the right on defense like this is a different story. two different concepts.

[raydog]

I tried a simulation of this hand. I fixed the cards for S2 + the turn, and gave S1 the AH. All other cards randomized. Here's what I found:

100,000 hands; 49,795 bid by S4 (alone or w/partner); 23,779 where S1 leads the AH. S2 plays:
JC: (3,545 / 16,349 / 3,885) [2 pts/ 1 pt / euchred] EV = +0.66 [perspective of S2/S4]
10S: (803 / 17,817 / 5,159) EV = +0.38
JD: (804 / 17,728 / 5,247) EV = +0.37
It seems that S2/S4 do best if S2 trumps with the R on the 1st trick. The advantages are:
- S4 knows where the R is;
- S2/S4 win the first trick if S4 happens to NOT be void in H.
While S2 would like to be able to lead the R early in the game and draw out enemy trump, it's unlikely they will ever get the lead and the chance to do so.

I tried replacing the R with the AC, then with the 9C, then tried giving S2 2 trump (9C + QC, no 10S); in all these cases, trumping on the first trick gave a better outcome.

What if S1 leads a non-A H? I first examined only a KH lead. I made sure S1 had the KH (all other cards random), but it was rare that S1 decided the KH was the best lead.

100,000 hands; 39,663 times trump called by S4 (with partner); 2,618 times KH led:
S2 plays trump: (227 / 1993 / 398) EV = +0.63
S2 plays 10S: (225 / 1968 / 425) EV = +0.60
This difference is perhaps too small to be statistically significant, but it does look like playing trump leads to a couple more sweeps and less euchres.

I then tested if S1 led ANY H other than the A, and didn't seed S1's hand with any particular cards.
100,000 hands; 37,556 times trump called by S4 (with partner); 6,261 times a non-A H led by S1:
S2 plays trump: (741 / 4,657 / 863) EV = +0.70
S2 plays 10S: (748 / 4,642 / 871) EV = +0.70
The KH was likely led very rarely, so we are looking at mostly Q or lower leads. Both sweeps and euchres rise slightly if trump is not played, so the results here are truly ambivalent.

From these tests I would conclude that it is best for S2 to trump an A lead by S1, even if that means using the Right bower. It's possible this also holds true for a K lead, but for Q and lower leads it is not clear if it is better to trump or duck. Reasoning? If an A is led and S2 ducks, the trick can only be won if S4 trumps. If a lower card is led, the trick can be won by S4 trumping but also by S4 having the highest in the led suit, hence the disappearance of the advantage of S2 trumping.

[irishwolf]

What is also critical in the Hand above from S2 perspective, is that he has two doubletons in the other two suits, and no lay Ace. Unless the Dealer wins the trick and leads trump, his ability to help is greatly reduced. If S2 could create a void, I would suggest he not trump.

Sloughing to an Ace led in generally, Poor Euchre Playing! Unless you know S1 is leading from three.

But the Dealer picks up and has the lowest 3 trumps. A hand generally resulting in a negative EV. It high probability if S2 slough a spade that the Dealer still gets euchred anyway.

S2 did his job, he got his trick!

IRISH

[Wes (aka the legend)]

I tried a simulation of this hand. I fixed the cards for S2 + the turn, and gave S1 the AH. All other cards randomized. Here's what I found:

100,000 hands; 49,795 bid by S4 (alone or w/partner); 23,779 where S1 leads the AH. S2 plays:
JC: (3,545 / 16,349 / 3,885) [2 pts/ 1 pt / euchred] EV = +0.66 [perspective of S2/S4]
10S: (803 / 17,817 / 5,159) EV = +0.38
JD: (804 / 17,728 / 5,247) EV = +0.37
It seems that S2/S4 do best if S2 trumps with the R on the 1st trick. The advantages are:
- S4 knows where the R is;
- S2/S4 win the first trick if S4 happens to NOT be void in H.
While S2 would like to be able to lead the R early in the game and draw out enemy trump, it's unlikely they will ever get the lead and the chance to do so.

I tried replacing the R with the AC, then with the 9C, then tried giving S2 2 trump (9C + QC, no 10S); in all these cases, trumping on the first trick gave a better outcome.

What if S1 leads a non-A H? I first examined only a KH lead. I made sure S1 had the KH (all other cards random), but it was rare that S1 decided the KH was the best lead.

100,000 hands; 39,663 times trump called by S4 (with partner); 2,618 times KH led:
S2 plays trump: (227 / 1993 / 398) EV = +0.63
S2 plays 10S: (225 / 1968 / 425) EV = +0.60
This difference is perhaps too small to be statistically significant, but it does look like playing trump leads to a couple more sweeps and less euchres.

I then tested if S1 led ANY H other than the A, and didn't seed S1's hand with any particular cards.
100,000 hands; 37,556 times trump called by S4 (with partner); 6,261 times a non-A H led by S1:
S2 plays trump: (741 / 4,657 / 863) EV = +0.70
S2 plays 10S: (748 / 4,642 / 871) EV = +0.70
The KH was likely led very rarely, so we are looking at mostly Q or lower leads. Both sweeps and euchres rise slightly if trump is not played, so the results here are truly ambivalent.

From these tests I would conclude that it is best for S2 to trump an A lead by S1, even if that means using the Right bower. It's possible this also holds true for a K lead, but for Q and lower leads it is not clear if it is better to trump or duck. Reasoning? If an A is led and S2 ducks, the trick can only be won if S4 trumps. If a lower card is led, the trick can be won by S4 trumping but also by S4 having the highest in the led suit, hence the disappearance of the advantage of S2 trumping.

Really good stuff Ray. This is a spot I've always wondered about and it's also a spot that's too tedious--at least for me--to test at the kitchen table. I've played it both ways--trumping in with the Right in that spot and playing off--and I never really developed any good intuition on it. Seemed like I always chose wrongly no matter what I did in this spot. Your work shows a pretty decent gap in EV between playing the Right vs playing off. That's really strong evidence that playing the Right here is best.

So strategy in this spot is clear to me:

1) If S1 leads an Ace, S2 should use his Right and trump in.

2) If S1 leads an offsuit King or worse, S2 should hold his Right back and play off.

Wolf makes an excellent point tho. What we hold in the other offsuit could change things. I'm betting it won't given the initial gap in EVs we already see but Wolf could be right. Even if Wolf ends up wrong his post is still excellent becuz he was thinking on a level no one else was thinking on.

[raydog]

Irish introduces a couple of unique twists:

1) If S2 has an off-Ace, I think that supports trumping, in order to lead the ace - let me know if I have misunderstood (an important consideration, just not undermining the prerogative to trump in this situation).

2) If S2 has a singleton, especially an off-suit, that could argue for playing off: if S4 is able to trump the 1st trick, they should view partner's discard as voiding themselves in a suit - very powerful. It's parlaying one void for a potential second winning void.

So I tested an initial hand of with turned. S4 calls C trump, and when S1 leads a non-A heart, S2 plays off with their KD to create a void in D (hoping S4 can win the 1st trick and lead back a D).

Here's what I found:
100,000 hands played; 36,476 called by S4; 7,257 a heart lead by S1 (non-A) and won by S4; 4,267 times S4 could lead back diamond [important to pay attention to the relative rarity of this particular sequence of events].
[note: the following is based on the instances of an non-A heart led by S1 and won by S2: 7,257 hands]

S2 wins with trump, leads KD: (1,033 / 4,716 / 1,508) EV = +0.52
S2 plays off (KD), S4 wins (higher H or trump) and leads back a D (when possible): (931 / 5,441 / 885) EV = +0.76

This gets rather confusing, but the idea is to isolate instances where 1) S4 calls C as trump; 2) S1 leads a non-A heart; and 3) S2 has the choice of trumping or discarding their KD [in the latter case, if S4 wins, they lead a D when possible]

It appears better for S2 to discard their singleton D rather than trump. This is really getting into the nitty gritty, as it is a rare choice for an equally rare hand, but it does validate Irish's intuition.

[Wes (aka the legend)]

Irish introduces a couple of unique twists:

1) If S2 has an off-Ace, I think that supports trumping, in order to lead the ace - let me know if I have misunderstood (an important consideration, just not undermining the prerogative to trump in this situation).

2) If S2 has a singleton, especially an off-suit, that could argue for playing off: if S4 is able to trump the 1st trick, they should view partner's discard as voiding themselves in a suit - very powerful. It's parlaying one void for a potential second winning void.

So I tested an initial hand of with turned. S4 calls C trump, and when S1 leads a non-A heart, S2 plays off with their KD to create a void in D (hoping S4 can win the 1st trick and lead back a D).

Here's what I found:
100,000 hands played; 36,476 called by S4; 7,257 a heart lead by S1 (non-A) and won by S4; 4,267 times S4 could lead back diamond [important to pay attention to the relative rarity of this particular sequence of events].
[note: the following is based on the instances of an non-A heart led by S1 and won by S2: 7,257 hands]

S2 wins with trump, leads KD: (1,033 / 4,716 / 1,508) EV = +0.52
S2 plays off (KD), S4 wins (higher H or trump) and leads back a D (when possible): (931 / 5,441 / 885) EV = +0.76

This gets rather confusing, but the idea is to isolate instances where 1) S4 calls C as trump; 2) S1 leads a non-A heart; and 3) S2 has the choice of trumping or discarding their KD [in the latter case, if S4 wins, they lead a D when possible]

It appears better for S2 to discard their singleton D rather than trump. This is really getting into the nitty gritty, as it is a rare choice for an equally rare hand, but it does validate Irish's intuition.

There's some problems here. First off, if S1 leads a non-Ace, S2 should not trump in with the Right in that spot no matter what his offsuit is. S2 should always throw off. That is so fundamental that even if a simulator suggested otherwise I wouldn't believe it. I would assume there's something wrong with the simulator.

If say S1 leads a non-Ace and S2 throws off a diamond and the maker, S4, takes the trick, that is not a cue for the maker to lead a diamond. That's actually a cue for the maker to always lead trump on trick 2. Why? Becuz once S2 plays off he has 1 of 3 holdings. He either has:

1) the Right
2) a guarded Left
3) no trump

For 1) and 2) it's self explanatory why S4 should always leas trump on trick 2. As far as 3)--those times S2 has no trump--that basically implies the enemy is more loaded in trump than usual and now it's critical that S4 lead trump to take out 2 enemy trump in one lead. Even if S4 started with just R+1+0 and spent his low trump on trick 1, he must lead the Right on trick 2 and hope for the best after that action.

Where Wolf's analysis is relevant are those times S1 leads an off ace. You work, Ray, on the hand in the OP demonstrates clearly to me that S2 should trump in with the Right on trick 1. But what wolf is saying is that may not be true depending on S2s other offsuit. Like if S2 can create a void maybe it's best to play off on the Ace lead in that situation. I'm betting it's still better to trump in with the Jack even if we could've created a void but I'm not sure. And once S2 does play off in this situation that's again a cue for S4 to always lead trump on 2nd Street. As far as I know, all strong teams play this way for reasons stated above, certainly the experts in my weekly tournament.

[raydog]

Very good analysis, Wes; I learned something. But if S4 is always going to lead back trump if they win the first trick (either with the highest card or with trump), and S2 only has 1 trump, what's the value in S2 getting void in a suit?

Perhaps S3 wins the first trick, and leads the suit S2 just voided herself in. But then we're back to the same decision as on trick 1: trump with the R or not? Let me know what I'm missing.

[Wes (aka the legend)]

Very good analysis, Wes; I learned something. But if S4 is always going to lead back trump if they win the first trick (either with the highest card or with trump), and S2 only has 1 trump, what's the value in S2 getting void in a suit?

Perhaps S3 wins the first trick, and leads the suit S2 just voided herself in. But then we're back to the same decision as on trick 1: trump with the R or not? Let me know what I'm missing.

You're not missing anything. There's isn't much value to S2 creating a void in this spot. This is partially why I'm betting that trumping an Ace lead with the Right is best even if S2 can create a void. The other reason I'm betting trumping in is best in this scenario is I just think the gap in EVs your work has already shown suggests to me our other offsuit is not gonna matter.

However there is an offsuit combination that COULD matter. Being able to create a void may not be important but what about those times S2 has 1 or even 2 aces. For example:

S4 calls clubs, S1 leads the AH and S2 has:



Should S2 play off on the Ace of heart lead--throwing away the JD--knowing that if his P wins the trick he will always lead trump on trick 2, which given S2s hand is really awesome for S2-4's team?

[irishwolf]

I DISAGREE:
"You're not missing anything. There's isn't much value to S2 creating a void in this spot."{

There is a very good reason for sloughing to create a void. 1) You played 2nd hand low, S4 wins the trick he leads trump. You now have two voids; 2 In case S3 wins the the trick and now leads back the same suit (S4 had a dblt) your are in a strong position to win the trick; 3) If S4 leads trump you also win the trick. The only downside is that you now have to lead from 3, but S4 will have a void, most likely, to that suit. 4) You trump a low first lead, you just may be taking a trick that the Marker (S4) could have won. He has better than a 50:50 chance of winning the trick. Let the Maker win it if he can. There is a fundamental in euchre, Never Steal the Captain's authority, it's Mutiny! However, a ace led is a different story! You have the void so the chance of him having a void is much lower.

NOTE TO 1) above: (Suppose S2 trumps the 1st trick) Then if S3 had a dblt and could have won the trick, S4 also has a doublton of the same suit. Both slough low and still has the winner to his (S4) off suit later in the hand!

You are in a far better situation to assist you partner than just trumping the trick.

IRISH

[raydog]

I have a question for the experts:

Say S4 calls trump in R1. My program currently generally trumps in from S2 on the first lead, when possible, even with a lone bower (their only trump). I'm getting the impression this is not ideal, but I'd like to know the parameters I should test.

My current thinking is along these lines:
1) OK to trump with a bower (only trump) if an Ace is led because it shows partner where the bower is, almost certainly assures winning the trick, and avoids wasting the bower if S4 were to otherwise win 1st trick and lead back the other bower;
2) also OK to trump with a bower if have a 2nd trump [not so sure about this one];
3) should play off (and create a void if possible) if K or lower led and are void in that suit.

Advice?

[Wes (aka the legend)]

I have a question for the experts:

Say S4 calls trump in R1. My program currently generally trumps in from S2 on the first lead, when possible, even with a lone bower (their only trump). I'm getting the impression this is not ideal, but I'd like to know the parameters I should test.

My current thinking is along these lines:
1) OK to trump with a bower (only trump) if an Ace is led because it shows partner where the bower is, almost certainly assures winning the trick, and avoids wasting the bower if S4 were to otherwise win 1st trick and lead back the other bower;

Yep, that's how I'd program it. And I wouldnt worry that there could possibly be some rare combos where this play is incorrect. Those hands would be so rare it wouldn't matter.

2) also OK to trump with a bower if have a 2nd trump [not so sure about this one];

This possibility should never exist as the simulator should have S2 calling every time he has R+1. The exception to the rule--hands like #7 in my quiz--are so rare they just don't matter.

3) should play off (and create a void if possible) if K or lower led and are void in that suit.

Advice?

Yep. Perfect. Always play off with the Right in that spot.

[irishwolf]

Agree with Wes!