[awm]

While I agree this hand does not lend itself to a sim, I'd suggest that my parameters have 5♦ making a lot more than it will in practice. After all, I removed all the hands where opener has 5♥ and max values (5♦ will almost never make then, since partner has little to nothing). I have opener bidding 4♥ with some semi-balanced minimum hands including six hearts that might not bid 4♥ in practice (5♦ will be better when opener has a flattish minimum than otherwise, usually). I've given responder 5-9 hcp, but it's not clear this is the right single raise range, and I suspect that people opening on 10-15 are more likely to play semi-constructive raises (or at least not make a limit raise on a flat 10-count) than the rest of the field. Again, this assumption reduces RHO's values, both increasing partner's and making spade finesses more likely to be on, and making 5♦ more likely to make. I've also included responder hands with four trumps (but not five) which might qualify for a preemptive raise -- these hands (where opponents have a huge heart fit and responder is minimum) also tend to increase our chances of making 5♦.

Really the tough part of simulating is determining when opponents will compete to 5♥ over 5♦ and when they will pass 5♦ out rather than doubling. Surely they will get this wrong sometimes and right others. I'm not even convinced that bidding 5♦ is wrong against "real" opponents (although I'm quite convinced it's wrong against double-dummy opponents). But saying "5♦ wtp" seems extreme.

[rogerclee]

awm, on Feb 8 2010, 01:24 PM, said:

I generated 20 hands where opener has 6+♥ and 10-15 hcp, responder has 3+♥ and 5-9 hcp. Here are the results for the various contracts. In some cases a double-dummy result differs from what seemed likely/possible at the table (i.e. a great lead was needed or some double dummy play in a suit).

(1) 4♥=, 5♦-2
(2) 4♥+1, 5♦-2
(3) 4♥-1, 5♦-2
(4) 4♥-1, 5♦-1
(5) 4♥=, 5♦-2 but 5♦-1 possible
(6) 4♥=, 5♦-2
(7) 4♥-1, 5♦-1
(8) 4♥-1, 5♦-2 but 5♦-1 possible
(9) 4♥+1, 5♦-2
(10) 4♥-1, 5♦-2 on trump lead, but 5♦-1 likely
(11) 4♥=, 5♦-1
(12) 4♥=, 5♦-1, but 5♦= likely
(13) 4♥-1, 5♦-2, but 5♦-1 possible
(14) 4♥-2, 5♦-1
(15) 4♥-1, 5♦-1
(16) 4♥=, 5♦-2
(17) 4♥-1, 5♦-2
(18) 4♥= but 4♥-1 possible; 5♦= on best play
(19) 4♥-1, 5♦=
(20) 4♥-1, 5♦=

Assuming opponents always double 5♦ and that we always obtain the best likely results for our sides (i.e. opponents don't make any spectacular leads or plays) I've got lose 9 for bidding 5♦, or lose 0.45 IMPS/board. Of course, it's occasionally possible that opponents would compete over 5♦ or fail to double, but that potentially also reduces some of the wins (i.e. opponents find good sac on 18-20, as well as maybe overcompeting some of the others). In addition, this is assuming opener always bids 4♥ with six of them and never without; in fact opener will sometimes bid 4♥ with only five, usually when holding max values (these are very bad cases for the 5♦ bid)... and opener might not always bid 4♥ with six when his hand is quite bad (reducing some of our best cases).

Inconclusive really, but I still don't think bidding is a "wtp"...

How did you IMP this (we are vul, they are not)? I thought your criteria were that 5D is always doubled and 4H is never doubled. I have:

1) lose 2
2) lose 2
3) lose 11
4) lose 6
5) lose 2 (win 6 if we are being generous)
6) lose 2
7) lose 6
8) lose 11 (lose 6 if we are being generous)
9) lose 2
10) lose 6
11) win 6
12) win 15
13) lose 11 (lose 6 if we are being generous)
14) lose 12
15) lose 11
16) lose 2
17) lose 11
18) win 15
19) win 12
20) win 12

Net: Lose 37 IMPs, or -1.85 IMPs/bd (Lose 19 IMPs, or -0.95 IMPs/bd if we are being generous)

[rogerclee]

Just want to add that I didn't feel strongly about bidding 5D or passing after reading the OP and still don't really.

1) I think awm's criteria that they will always double 5D is very unrealistic.
2) I trust awm's analysis of the simulations and his numbers do not seem particularly hard to believe to me.
3) I think the opponents will seldom bid 5H over 5D (Adam, did you simulate any hands where you found this to be likely or even reasonable?), their decision will mostly be to double or pass.

[billw55]

I don't know what to say about shrugging aside such strong sim results. In 20 deals, 4♥ is down 11 (!!) times, and 5♦ only makes two of those times. In total minus at least an IMP per board, per Roger's analysis. This is so overwhelming that even if reality would help 5♦ a little (which is not at all clear considering awm's points) it still will be a loser IMO.

Try dealing a larger sample, but allow opener to have 5 hearts and a max, which is very reasonable. There is no rule that says ops don't have their bid just because the colors favor them. I bet 5♦ does even worse.

[655321]

I would always bid 5♦ here, if only because it seems too weird to have 9 tricks with diamonds as trumps, and never say the word diamond.

I don't think the simulation is at all reliable, and I think it would be very difficult to simulate.

But just for fun I did the IMPs too:

rogerclee, on Feb 8 2010, 09:14 PM, said:

awm, on Feb 8 2010, 01:24 PM, said:

(12) 4♥=, 5♦-1, but 5♦= likely
(14) 4♥-2, 5♦-1
(15) 4♥-1, 5♦-1
(18) 4♥= but 4♥-1 possible; 5♦= on best play
(19) 4♥-1, 5♦=
(20) 4♥-1, 5♦=

Assuming opponents always double 5♦ and that we always obtain the best likely results for our sides (i.e. opponents don't make any spectacular leads or plays) I've got lose 9 for bidding 5♦, or lose 0.45 IMPS/board.

Inconclusive really, but I still don't think bidding is a "wtp"...

How did you IMP this (we are vul, they are not)? I thought your criteria were that 5D is always doubled and 4H is never doubled. I have:

12) win 15
14) lose 12
15) lose 11
18) win 15
19) win 12
20) win 12

Net: Lose 37 IMPs, or -1.85 IMPs/bd (Lose 19 IMPs, or -0.95 IMPs/bd if we are being generous)

Roger, I get

12) win 14
14) lose 7
15) lose 6
18) win 14
19) win 11
20) win 11

for a total of -31 when 5♦ is doubled every time it goes down.

If 5♦ is never doubled, we would score +49 IMPS over the same 20 boards by bidding 5♦.

[rogerclee]

655321, on Feb 9 2010, 08:18 AM, said:

I would always bid 5♦ here, if only because it seems too weird to have 9 tricks with diamonds as trumps, and never say the word diamond.

I don't think the simulation is at all reliable, and I think it would be very difficult to simulate.

But just for fun I did the IMPs too:

rogerclee, on Feb 8 2010, 09:14 PM, said:

awm, on Feb 8 2010, 01:24 PM, said:

(12) 4♥=, 5♦-1, but 5♦= likely
(14) 4♥-2, 5♦-1
(15) 4♥-1, 5♦-1
(18) 4♥= but 4♥-1 possible; 5♦= on best play
(19) 4♥-1, 5♦=
(20) 4♥-1, 5♦=

Assuming opponents always double 5♦ and that we always obtain the best likely results for our sides (i.e. opponents don't make any spectacular leads or plays) I've got lose 9 for bidding 5♦, or lose 0.45 IMPS/board.

Inconclusive really, but I still don't think bidding is a "wtp"...

How did you IMP this (we are vul, they are not)? I thought your criteria were that 5D is always doubled and 4H is never doubled. I have:

12) win 15
14) lose 12
15) lose 11
18) win 15
19) win 12
20) win 12

Net: Lose 37 IMPs, or -1.85 IMPs/bd (Lose 19 IMPs, or -0.95 IMPs/bd if we are being generous)

Roger, I get

12) win 14
14) lose 7
15) lose 6
18) win 14
19) win 11
20) win 11

for a total of -31 when 5♦ is doubled every time it goes down.

If 5♦ is never doubled, we would score +49 IMPS over the same 20 boards by bidding 5♦.

You are right on 14+15, but I also said they would double when 5D makes; seems unfair to assume they will only double 5D when it's down.

[Fluffy]

thanks for the politeness and that, but no joke, I would bid 3♦ round before and didn't think it was close, I have no tool avaible to find the heart stopper starting with a double either, and a vul vs not 3♦ live bid opposite a partner who didn't act over 1♥ shows already a VERY good hand, my plan is to double 3/4♥ next wich will put me in a much better position, if 3♦ is passed out I don't think I would had done any better by doubling first.

Its maybe a style Issue, in the last 10 years I can count with my ingers the times where me or dad doubled first with a one suiter. The ones that happened above the 1 level had 11 sure tricks

[jdonn]

Fluffy, on Feb 9 2010, 01:59 PM, said:

if 3♦ is passed out I don't think I would had done any better by doubling first.

Really?

[Fluffy]

I am making it, ain't I?

seriously, double then 3♦ over 2♠ would show a 3154 very strong rather than these. And on any other scenario it seems better to have been able to bid diamonds before.

[awm]

rogerclee, on Feb 9 2010, 12:25 PM, said:

You are right on 14+15, but I also said they would double when 5D makes; seems unfair to assume they will only double 5D when it's down.

Fixing this and using the "generous" assumptions gets us back to my original result that bidding 5♦ lost 9 imps on 20 boards.

Again, I don't think this is particularly conclusive. Certainly the opponents might judge wrong sometimes and bid 5♥, or fail to double. And the set of hands where opener bids game (or where responder bids 2♥) is not exactly right.

However, I do think the following can be concluded:

(1) You're not going to actually make five diamonds very often.
(2) If the opponents make "double dummy" competitive decisions, bidding 5♦ is a big loser.
(3) Against real opponents I don't think this really tells you much, but the first two statements suggest that it is at least a close decision. It may depend on stylistic things (what is the range of the 2♥ raise for these opponents, how often do they jump to 4♥ "obstructively" rather than intending to make, how aggressive are they in competing vs. doubling at the five-level, etc).

[jdonn]

I still don't really believe statement 1 though I might have overestimated it myself. It's like Mike's 30 hands, frankly I don't see why I should believe it when to me it feels so untrue.

I believe 2 is definitely true but not the slightest bit relevant. I've said many time how incredibly awful many of the actions I regularly take would work out if my opponents were double dummy over them. It's just a really hard auction to double us when I could easily be sound for my bid, responder doesn't know the nature of opener's hand, and opener could be long in hearts and not be sure himself.

Think of the actual hand. We went for 800, but even opposite partner's actual hand,
- Diamonds were 0-5, so probably at least some wests would bid 5♥ on their diamond void before their partner would get to double.
- If diamonds were 1-4 then we lose 2 imps if they double and gain 6 if they don't, plus the chance an opponent could still make a bad 5♥ bid like RHO who knows he has nothing wasted in diamonds.
- If diamonds were 2-3 or 3-2 then we are even less likely to be doubled. While they might have been down in that case it's less likely given that they bid game to begin with, and clubs could still be not breaking as well.
- Partner had a yarb with a stiff diamond!