The Muiderberg Hoax

[32519]

Two weeks back, you couldn't properly write a Muiderberg sim because you didn't understand the definition of the opening.Now you're lecturing people on how it should be played...

Yes...

...and besides...

.................no one has yet convinced me that I'm wrong!

[gwnn]

.................no one has yet convinced me that I'm wrong!

Maybe you should stop opening hundreds of threads if you then go on and ignore the thousands of replies you receive. The only replies you maybe take seriously are the joke posts in the Secret Bridge Olympics thread.

[barmar]

Interesting, Rik. In the ACBL no convention can legitimately be "explained" just by naming it — including Stayman, which of course "everybody knows" what it means.

Then again, no one ever asks for an explanation of 1NT-2♣, so the issue doesn't actually come up.

[mycroft]

Oddly enough, they do when we do it (of course, it's Alerted, and I'm a known TD and rules stickler, so there is some incentive to ask)

 

Edit: at one point we had the following auction:

 

South: 1NT

North: "12-14"

West: 2♣

East: "Alert"

North: "Please Explain"

East: "She wants me to bid 2♦ so she can show her hand"

 

Now, I knew both that that is at *best* incomplete information (and effectively useless), but I was *so* hoping that partner would double so that:

 

North: X

South: "Alert"

East: "Please Explain"

South: "She wants me to bid 2♦ so she can show her hand"

 

Note that our normal explanation is "she either wants to play 2♦, or has one of several invitational or better hands." But I just wouldn't have been able to resist.

[sfi]

Then again, no one ever asks for an explanation of 1NT-2♣, so the issue doesn't actually come up.

 

This just goes to highlight regional differences. In Australia everyone asks for an explanation on this auction because it is played so many different ways. We occasionally get pitying looks for our Neanderthal system when we reply 'simple Stayman, asking for a four card major but doesn't promise one'.

[Avoidance]

My experience with these sort of bids at Pairs over a number of years is that Vulnerability is critical. With 5-4 they are +EPV Non-vulnerable & -EPV

Vulnerable.

[Vampyr]

4-4 was even possible on a Friday night, and I suspect even 4333 in the hands of its creator ...

 

Fair enough, because he plays the spots off the cards.

 

The only replies you maybe take seriously are the joke posts in the Secret Bridge Olympics thread.

 

That is totally my favourite thread.

 

Then again, no one ever asks for an explanation of 1NT-2♣, so the issue doesn't actually come up.

This just goes to highlight regional differences. In Australia everyone asks for an explanation on this auction because it is played so many different ways. We occasionally get pitying looks for our Neanderthal system when we reply 'simple Stayman, asking for a four card major but doesn't promise one'.

 

So in Australia and USA Stayman is alerted rather than announced?

[blackshoe]

I don't know about Australia, but in the US Stayman is neither alerted nor announced.

[barmar]

I don't know about Australia, but in the US Stayman is neither alerted nor announced.

Right. My comment above was in reference to an unalerted 2♣ response. If it's alerted, I would certainly expect opponents to ask, since in the ACBL the alert implies that the pair is not using some form of Stayman.

[sfi]

So in Australia and USA Stayman is alerted rather than announced?

 

In Australia, a 2♣ response to an opening 1NT is never alerted. It's defined as 'self-alerting', just like doubles, redoubles, and bids above 3NT (except for opening bids). There is no concept of announcements in Australia, although it may be introduced in the near future.

[Trinidad]

Interesting, Rik. In the ACBL no convention can legitimately be "explained" just by naming it — including Stayman, which of course "everybody knows" what it means.

I don't know whether this list still exists, but there used to be a list of abbreviations for WBF convention cards. It contained, among others:

 

F1: Forcing for one round

GF: Game forcing

SPL: Splinter

STAY: Stayman

SUPP: Support

 

The fact that the WBF allows an abbreviation for Stayman as an explanation on its CCs indicates that they consider 'Stayman' to be an appropriate description (at least for CC purposes). Seen in that light it isn't that strange that an NBO allows players to explain some of the most popular conventions by their name, even if it is a big no-no in the ACBL.

 

Rik

[32519]

Netherlands is a bit of the land of secretary birds so you will get lynched if you disclose your 5-5 agreement as Muiderberg. It must be exactly 5 in the major and 4-8 in the minor. Sometimes people will call it Muiderzand, Modderheuvel etc because they are afraid of running into troubles with opps or directors with idiosyncratic ideas about what exactly "Muiderberg" is supposed to mean.

I will say this one more time. To specify Muiderberg as 5M4-8m is nothing but a hoax, maybe to intimidate all players from novice to intermediate. I don’t believe that players from advanced upwards will fall for the hoax. Just look at these odds:

1. Exactly 5M4m 5-10 HCP = 1.03% X 2 = 2.06%

2. Exactly 5M5m 5-10 HCP = 0.32% X 2 = 0.64%

3. Exactly 5M6m 5-10 HCP = 0.05% X 2 = 0.10%

4. Exactly 5M7m 5-10 HCP = ?

5. Exactly 5M8m 5-10 HCP = ?

 

The last two are so remote that BBOs deal generator fails to spit out a probability percentage. To open 5M4m when red or partner is already a passed hand is just asking for trouble. No doubt there are some who OCCASIONALLY DO OPEN A 5M4m Muiderberg (most likely when the HCP are concentrated in the minor suit and white and 1st or 2nd seat). I HAVE NEVER SEEN A 5M4m MUIDERBERG AT THE TABLE. IT HAS ALWAYS BEEN 5/5.

 

Calling it Modderheuvel is appropriate. Translated into English it means Mud-Hill!

 

Go figure?

[Zelandakh]

Now calculate the size of the minor suit fit given that Responder has 0-1 cards in the major and, for simplicity, 3+ cards in both minors. Things are slightly more rosy than this due to tricks such as those alluded to earlier (sometimes we can get out in Responder's suit instead) but that is probably too difficult for you to model. Incidentally, I recommend you switch to using percentages of hands given that a Muiderberg 2M was opened - it makes the numbers clearer and should make it easier for you to spot your statistical errors. oh yes, and noone is specifying Muiderberg as 5M-8m; but to specify it as 5M4m would clearly be misinformation when 5-5s are a significant part of the hands held. Something you need to understand is that not all 5-4 hands in range are opened 2M and that needs to be factored into your numbers.

[gwnn]

No need to repeat your uninformed, vacuous opinion 32159 times. We understood you the first time. All posters from NL and BE have laughed at you and told you you were wrong. Nobody even said that you were possibly right (I told you that I prefer 5-5 when vulnerable but very few people play it that way). Using caps will also not help.

[32519]

Now calculate the size of the minor suit fit given that Responder has 0-1 cards in the major and, for simplicity, 3+ cards in both minors. Things are slightly more rosy than this due to tricks such as those alluded to earlier (sometimes we can get out in Responder's suit instead) but that is probably too difficult for you to model. Incidentally, I recommend you switch to using percentages of hands given that a Muiderberg 2M was opened - it makes the numbers clearer and should make it easier for you to spot your statistical errors. oh yes, and noone is specifying Muiderberg as 5M-8m; but to specify it as 5M4m would clearly be misinformation when 5-5s are a significant part of the hands held. Something you need to understand is that not all 5-4 hands in range are opened 2M and that needs to be factored into your numbers.

OK, so took up your challenge. I rejected your 3+ suggestion and went for 4+ instead to ensure our side has at least a 4/4 fit. This is what I got:

1. 0-10 HCP, 0-1M, 4m4m in the minors = 1.84%

2. 11-30 HCP, 0-1M, 4m4m in the minors = 1.44%

3. Combined = 3.28%

 

Why 0-10? If partner opened with 10 HCP and I also hold 10, then the HCP are split evenly between the two sides.

Why 11-30? If partner opened with 10 HCP I cannot hold more than 30.

 

Still doesn’t look too great when partner is a passed hand or you are red.

[Zelandakh]

You seem to have missed the point. What you need to discover is the % of time when we open a Muiderberg 2M that we play in a 7 card fit at the 3 level, which was the scenario you were lecturing us about. Not only does your last post answer a completely different question, it also gives contradictory numbers (combined 3.28% when the post before gives % of Muiderberg hands as 2.80%). Now I am sure the numbers are all correct and everything but unless you can explain them clearly they are meaningless. This is why I suggest you switch to conditional probabilities for Muiderberg openings. Because I have no idea how often you think we are playing 2M and how often 3m based on your statistics. Nor the percentages for 7, 8 and 9+ card fits. Nor the expected number of tricks. In fact, I cannot find any meaningful information anywhere despite the forceful conclusions you are deriving from the numbers.

[MrAce]

.................no one has yet convinced me that I'm wrong!

 

I thought...

 

In order to try to convince you that you are wrong, one has to convince himself that you are convincable....Na.. i don't think anyone who has seen your ignorance and who has seen that you are wrong in so many things, in this topic as well as in the past, will ever gonna waste his/her time for this.

 

But looking at the replies, obviously i was wrong.

[barmar]

The fact that the WBF allows an abbreviation for Stayman as an explanation on its CCs indicates that they consider 'Stayman' to be an appropriate description (at least for CC purposes). Seen in that light it isn't that strange that an NBO allows players to explain some of the most popular conventions by their name, even if it is a big no-no in the ACBL.

Allowing a shorthand on the CC does not necessarily mean that just naming the convention is adequate disclosure. The ACBL convention card is full of checkboxes for common conventions and treatments, but ACBL Alert Procedures says that when someone asks for an explanation you must describe the meaning, NOT just name a convention. The point is that a CC and an explanation are different -- there isn't room on a piece of paper for detailed explanations, the CC is just a summary.

[Wackojack]

Since I play Muiderberg with 1 regular partner, I thought I would do a quick and admittedly rough check on the perils of finding that you have to play in a 4-3 minor fit at the 3 level. In Playbridge I specified 1 hand to be ♠A10965; ♥ 8; ♦J86; ♣Q1098. This was meant to show a typical absolute weakest hand that he might open 2♠ vulnerable. This (just) breaks the criteria (7 points in the long suits vul)that we agreed but I know what my partner is like. The opposite hand I gave 6-11 points any distribution. 32 deals.

When this hand is dealt a singleton spade, I judged that you would respond 3♣ pass or correct.

 

Results:

4-4 came up twice and 4-3 twice.

Of the 4-3's

1. Opps had 3NT game on and unlikely to go for a penalty even at green.

2. Opps had part score and 4-3 fit goes 2 off.

 

Otherwise I dont see any obvious (possible) bad results. I don't have time to analyse the possible good results.

[campboy]

4. Exactly 5M7m 5-10 HCP = ?

5. Exactly 5M8m 5-10 HCP = ?

 

The last two are so remote that BBOs deal generator fails to spit out a probability percentage.

This is another reason not to use simulations when you don't have to. The probability of a random hand having exactly 5 spades and 7 clubs and 5-10 HCP is 1 in 22340. For 8 clubs it is 1 in 757204.

[hrothgar]

This is another reason not to use simulations when you don't have to. The probability of a random hand having exactly 5 spades and 7 clubs and 5-10 HCP is 1 in 22340. For 8 clubs it is 1 in 757204.

 

When brute force doesn't work, this is usually a sign that you need to apply more brute force...

[32519]

Now here's a thought.

The trend is towards a Weak Only Multi, 5-9 HCP. The 2♥ and 2♠ bids being used for a sound weak 2 in the suit, 10-13 HCP. Stated differently, the trend is away from Muiderberg.

[hrothgar]

Now here's a thought.

The trend is towards a Weak Only Multi, 5-9 HCP. The 2♥ and 2♠ bids being used for a sound weak 2 in the suit, 10-13 HCP. Stated differently, the trend is away from Muiderberg.

 

The expression "thought" suggests that "thinking" took place, so this hardly seems like an appropriate description...

Rather, this is an example of an anecdote from another thread being confounded with the posters own biases and used to claim a trend.

 

If you want to contribute something of actual value, why not go to ECATs and record the what the 2D and 2M opening bids showed over time.

(I collated this information for a few years, you can probably find this information)

 

Once you've collected an adequate time series - and compensated for geographic effects - you might be able to make a few founded claim that there is/ is not a "trend"

[PhilKing]

thought.

 

The "trend" is purely a function of how many English posters who happen to use constructive weak twos post on BBO.

 

Visit a Dutch bridge club and you would doubtless draw an entirely different false conclusion.

[Free]

The trend is towards a Weak Only Multi, 5-9 HCP.

LOL