[kenberg]

This came up playing with the bots in a 39 cent tourney but the sequence could be of interest to humans as well. Rho deals and opens 1♥, I double, and it continues as follows:
1♥ - X - 2♥ - X
P - 3♦ - 3♥ - 4♠

Hmm. My usual style is to not read the bots alerts, I like to keep it like a normal game where I am supposed to know what partner means without looking. I took his first double as responsive, meaning I should choose a minor. But now I decided to look. I figured 4♠ is some sort of choice of games offer. It's a good thing I looked.

http://tinyurl.com/yxpsndwo
As you can see, the bot explains that the X opposite my take-out X was Responsive (as I thought) and that it shows 4+ ♠.

Not the way I play responsive doubles. I assume that had he chosen 2♠ or 3♠ or 4♠ these calls would also show 4+ ♠. How many ways do we need to show 4+♠? I could agree that the responsive double does not necessarily deny four ♠. If he is, say, 4=0=5=4 perhaps making a responsive double followed by 4♠ could be a way to say "Hey pard, I have four ♠ but just in case you made your take-out on a three card holding maybe you want to pull to 5m." That seems possible, although I think it should instead show a strong three card ♠ holding and offer a choice of 4♠ or 5m. But here the alert says that the responsive double actually promises 4+ and, moreover, he made the call with five. Whatever I thought, I was not expecting five. Until I read the alerts.

I am interested in what my fellow humans would make of the 4♠ call. Of course the bots can also weigh in on this if they like.

[etha]

Humans don't agree either. You specifically have to agree that either it can have 4 spades or that it never has 4 spades. Sometimes this even changes depending on the level you are at e.g. 1♥ dbl 4♥ dbl

Now it is much more likely you might want to show 4 spades here than over 2♥ when you can bid them more easily.

[pescetom]

etha, on 2019-May-06, 10:49, said:

Humans don't agree either. You specifically have to agree that either it can have 4 spades or that it never has 4 spades.

This human agrees with @kenberg. I don't see why it has to have 4 spades in the OP example.

etha, on 2019-May-06, 10:49, said:

Sometimes this even changes depending on the level you are at e.g. 1♥ dbl 4♥ dbl

Now it is much more likely you might want to show 4 spades here than over 2♥ when you can bid them more easily.

As you say, it changes depending on on the level, so what need is there for a blanket always/never agreement?

[HardVector]

The best place to get answers on this is to read a book from an authority. The way I learned responsive doubles was from Max Hardy, and his recommendation was that if they are bidding a major, a responsive double promises both minors and denies the other major. If they are bidding a minor, the responsive double promises both majors. There is a third occasion he brings up, but it's not applicable here.

[barmar]

We changed the bot's definition of responsive double about 7 years ago. We had an internal discussion at the time, and I argued for the Hardy style, but Uday and Fred preferred this. Fred wrote:

Quote

I don't think there is any clear standard here.

My personal preference is similar to Uday's (or another way to put it, the responsive double suggests that ability to control the auction - if partner bids his cheapest 4-card suit then nothing bad will happen to you).

But there are definitely plenty of people out there who think like Barry does (responsive double explicitly shows the minors or, a slightly more sophisticated version, is that if the opponents have bid spades that responsive DBL is normally the minors but might also include an invitational hand in hearts).

Not sure what is best here either in terms of the bridge issue or (more important) telling GIB what to play. My sense is that we might do best to define the responsive DBL as value-showing (say 8+ HCPs) with no 5-card or longer suit. I think this might be smart because:

- probably most of our users have not thought deeply (or at all for that matter) about such issues
- no clear standard on what shape people expect for responsive DBL
- this will probably be easiest to code

[kenberg]

Added: This was written before I saw Barry's post directly above it.
I am very much in agreement that conventions need to be discussed and, for most of us, looking it up in a trusted source and just doing it that way is effective. In this case I thought I would just present it as an auction that might occur w/o previous discussion, as is often the case on BBO games.

But I checked Mike Lawrence The Complete Book of Takeout Doubles (1994) and indeed he says that double of 2♥ shows 4-4 in the minors (or, presumably, possibly better) and enough strength to play at the 3 level. Same as I, and I think most people, play it.

I have played with the bots a fair amount, enough so that this is not the first time the responsive double has come up, and I don't recall any previous confusion. The bots have, I think, been updated and I am wondering if ths is a change, and if it is intended.

But bots aside, just between us bipeds, what should this auction mean? I imagined fourth hand as strong (of course) with something like ♠KJx and a stiff ♥. If the original doubler has a strong four card ♠ suit this may well play fine in 4♠, while if he has a weak suit, and thus hopefully strength in the minors, it might be best to play in 5m. If you woke me in the middle of the night and told me I must interpret this undiscussed auction, I think that is what I would come up with.,

Lawrence recommends responisive doubles through 4♦ by the opponents. Just for amusement, I note that we are white against red and 4♥ X goes for 500, or at least it can.

Another question comes to mind: That's a pretty good hand N has. Both my X and my 3 ♦ were perhaps pushy. If I had a decent spade suit and some extra values, maybe we belong in 6♠. Maybe that's what my robotic friend had in mind. Given that 6♠ might seem like a reasonable possibility to N, just what should he do over the 2♥?

[cherdano]

I don't know any human who'd ever make a responsive double with 5 spades in this auction. Yes there are different styles about what to do with 4 spades. But noone doubles with 5 spades.
It sounds like Fred agrees from the excerpt of the email quoted by Barry.

[kenberg]

barmar, on 2019-May-06, 12:48, said:

We changed the bot's definition of responsive double about 7 years ago. We had an internal discussion at the time, and I argued for the Hardy style, but Uday and Fred preferred this. Fred wrote:

Thanks greatly. As you can probably guess, the post lying right after yours was written when I had only seen the one just before yours.

I am surprised I never noticed this before, but sometimes it takes something fairly dramatic to get my attention. I will keep it in mind when playing with the bots.

As mentioned, I still think that the responsive X, followed by 4♠, is interesting to us non-bots who accept the general notions of Hardy (and I think a fair number of others). I see it as showing a strong three card ♠ holding, offering a choice of games. I repeat, that is conditional on playing Hardy style, not bot style.

Back to bot style for a moment. What would a jump to 4♠ show over the 2♥? Actually I can think of a host of questions stirred up by that auction, both for bots and humans.


Again, thanks