variable NT range

[nullve]

I agree with what helene_t said, except that I think she forgot to mention that 'range' is also used (esp. in her field, statistics) in the sense of a difference between extreme values, in which case range of the set {10,11,12,13,14,15} is 15-10=5, not 6. So I can sort of understand the confusion.

[PeterAlan]

In mathematics, a range is set, not a number. When we assign a number to a range it is its size or length. If HCP are real numbers, then the range "10-15" is the interval [10.0, 15.0] which has length 5.0. If HCP are whole numbers, then the range "10-15" is the set {10, 11, 12, 13, 14, 15}; this set does not have a length but it has size (cardinality) 6.

Look up the definition of range as it pertains to math to see where you are wrong.

Robin is someone who studied mathematics to doctorate-candidate level at arguably the strongest mathematics faculty in the UK, and knows whereof he speaks. There is more to the subject than definitions from MathGoodies. This kind of gratuitous rudeness is out of order.

 

Peter

[barmar]

We get it - English is not as precise as mathematical terminology. Nonetheless, everyone else seems to understand the meaning of range in this context with no difficulty. The regulations may be easier to navigate if you don't try so hard to misconstrue their intent.

I suspect that very few people even think about it, because hardly anyone plays a NT range that's large enough for it to matter what definition is used. Whether 15-17 is 2 or 3 is irrelevant when the regulation only cares about 5 or more. The only people who need to worry about the definition of "range" are those playing something like 10-15 NT. I don't think I've ever encountered something like that until this thread.

[barmar]

The part on the GCC about "including those that have non-consecutive ranges" means that for this purpose your range is 10-21, a 12 point range (not 11), so conventions would not be allowed.

How do you get that? If it's high-low it's 11. If it's the number of possible HCP values, it's 4 (10, 11, 20, 21). I don't see why you should count all the HCP values in the gap between the two ranges if you're using cardinality as the definition.

[jeffford76]

How do you get that? If it's high-low it's 11. If it's the number of possible HCP values, it's 4 (10, 11, 20, 21). I don't see why you should count all the HCP values in the gap between the two ranges if you're using cardinality as the definition.

 

In that case it doesn't matter anyway. The point was that the regulation is intended to prohibit conventions over something like 10-12 or 16-17. I believe it's also intended to prevent 10-11 or 14-15 (counting it as a six point range), but I don't have any special document I can point to for that.

[blackshoe]

In that case it doesn't matter anyway. The point was that the regulation is intended to prohibit conventions over something like 10-12 or 16-17. I believe it's also intended to prevent 10-11 or 14-15 (counting it as a six point range), but I don't have any special document I can point to for that.

Neither, I suspect, would anyone in Horn Lake, if you asked them.

[Shugart23]

I actually think ken might have a valid point. If 10 to 13 is allowed if white and 13 to 15 is allowed if not whitr and this scheme is not considered a 6 point range, then just change the words white and not white to be hearts and no hearts. What is the difference?

[Vampyr]

I actually think ken might have a valid point. If 10 to 13 is allowed if white and 13 to 15 is allowed if not whitr and this scheme is not considered a 6 point range, then just change the words white and not white to be hearts and no hearts. What is the difference?

 

LOL not sure you could fool even the thickest director with this argument!

[jnichols]

I actually think ken might have a valid point. If 10 to 13 is allowed if white and 13 to 15 is allowed if not whitr and this scheme is not considered a 6 point range, then just change the words white and not white to be hearts and no hearts. What is the difference?

The difference is that everyone in the room can tell which of white or not white apply. The announcement should either be "10-13" or "13-15", not some combination. On the other hand if its hearts or no hearts no one except the opener knows which one applies. And that is a huge difference.

 

 

 

[Shugart23]

And yet the 'rule' doesnt make this distinction so this is perhaps your interpretation of the rule and not the literal reading of it. But yeah, its out of the box and probably a stretch

[campboy]

And yet the 'rule' doesnt make this distinction so this is perhaps your interpretation of the rule and not the literal reading of it. But yeah, its out of the box and probably a stretch

Of course it does. You're not allowed to play conventions after "natural notrump opening bids [...] with a range of greater than 5 HCP". If you open 1NT, not vul, all that matters is the range of that particular opening bid, and 10-13 is fine. The fact that a different notrump opening bid might have a different range is irrelevant -- just as irrelevant as the fact that in standard a notrump opening could be 15-17 or 20-22 depending on what level it is at (the regulation doesn't say anything specifically about 1NT, after all).

[gwnn]

Can't believe that nobody called out this blatant racism in this thread.

 

(sorry, couldn't help myself.)

[jallerton]

In mathematics, a range is set, not a number. When we assign a number to a range it is its size or length. If HCP are real numbers, then the range "10-15" is the interval [10.0, 15.0] which has length 5.0. If HCP are whole numbers, then the range "10-15" is the set {10, 11, 12, 13, 14, 15}; this set does not have a length but it has size (cardinality) 6.

 

 

.

 

Look up the definition of range as it pertains to math to see where you are wrong.

 

 

Robin is someone who studied mathematics to doctorate-candidate level at arguably the strongest mathematics faculty in the UK, and knows whereof he speaks. There is more to the subject than definitions from MathGoodies. This kind of gratuitous rudeness is out of order.

 

Peter

 

True, Robin is an expert in mathematics, but Robin's studies may not have extended to anything called "math".

[Shugart23]

Of course it does. You're not allowed to play conventions after "natural notrump opening bids [...] with a range of greater than 5 HCP". If you open 1NT, not vul, all that matters is the range of that particular opening bid, and 10-13 is fine. The fact that a different notrump opening bid might have a different range is irrelevant -- just as irrelevant as the fact that in standard a notrump opening could be 15-17 or 20-22 depending on what level it is at (the regulation doesn't say anything specifically about 1NT, after all).

 

 

 

I know what you are saying. I can still also see kens argument that opening 1nt in the heart/no heart scenerio is indeed a 3 point range. It is just that nobody knows which range it is until the rebid. Having said that, i am not going to try it !

[helene_t]

You could also try:

 

12-14 if I have less than 15 points

15-17 otherwise

[gnasher]

If I bid shows something that shows a 10-count, would JohnU call that a 0-point range?

[szgyula]

If I bid shows something that shows a 10-count, would JohnU call that a 0-point range?

 

I could. The problem is that there are two meanings to "range": you can interpret it as "span" (10-count is 0 span/range) or as the number of elements in a set (10-coount has one element, i.e. range is one).

 

This is even more complicated for non touching intervals. It it the max-min? Is it the sum of the disjunct spans? Is it the number of elements?

 

One can argue forever and there is no clear answer. Points are discrete things normally so some would argue for the "set based" definition. On the other hand, some people subtract 0.5 points for a 4333 distribution or no 9/10 cards, etc and the 1NT is 15 to 17.5 points. Now what is the range?

[campboy]

I know what you are saying. I can still also see kens argument that opening 1nt in the heart/no heart scenerio is indeed a 3 point range. It is just that nobody knows which range it is until the rebid. Having said that, i am not going to try it !

The range is the possible values it might be, not what the hand actually is. Otherwise you could say any 1NT opener is a 1-point range (it's just that nobody apart from opener knows which 1-point range it is yet).

[Shugart23]

The range is the possible values it might be, not what the hand actually is. Otherwise you could say any 1NT opener is a 1-point range (it's just that nobody apart from opener knows which 1-point range it is yet).

 

 

 

That is a pretty good interpretation of the rule (and almost convincing), but by your interpretation, 1NT =10-11 OR 19-20 is allowed because there are only 4 possible values...But we know this is not true, so your interpretation ( "the range is the possible values it might be")is not right.

 

 

 

What we all can agree on is that either having 4 hearts or not having 4 hearts are two mutually exclusive events. And we can all agree that 10-13 is a 4 point range and having 14-17 is a 4 point range. We all can agree that if I always open 1NT promising 4 hearts and 10-13 HCP, that this would be allowed...We also can agree if I always open 1NT denying 4+Hearts and 14-17 HCP that this would also be allowed.

 

The overwhelming interpretation of the rule is that combining these two mutually exclusive events somehow means I would be opening a hand that has a wide 10-17 HCP range, which is definitely not the case...Every hand that would opened one NT would have a very specific 4 point range due to the mutually exclusiveness of the two cases (Hearts or no Hearts) and then on the rebid, everyone at the table finds out which case it is..10-13 or 14-17.

 

The rule doesn't say the Opponents have to know what the range is immediately; this is an interpretation of the rule The rule simply says the range has to be less than 5 (which it always will be) and , elsewhere,that the Opponents are entitled to know what the partnership agreement is.

 

Clearly I have way too much time on my hands and need to focus instead on rooting for the Packers....

[blackshoe]

All of my bridge life, everything i've ever read about point ranges said that 10-12, for example, is a 3 point range, 20-21 is a two point range, and 6-10 is a 5 point range. Until now. The real question is "what's the range of two non-consecutive ranges?" If for some reason you play "either 10-12 or 15-17" this is clearly two non-consecutive ranges, both 3 points. I think the regulation, when it refers to something like this, means "add the ranges together" so this would be 6 points, not 8, and thus if this describes your 1NT opening, you can't play conventions after it. If you changed it to "either 11-12 or 15-17" or "either 10-12 or 15-16" or even ""either 10-12 or 16-17" you'd be fine.

 

Note that this "split range" agreement is not based on vulnerability, or seat, or phase of the moon, or anything else. If you play different 3 point ranges based on something like this, your range is 3 points.

 

That's my take, and that's how I'd apply the law.

[Shugart23]

Yeah. I actually agree with the consensus but i am really just exploring the twist of having mutual exclusive events (hearts and no hearts) which is not only unusual but perhaps not even anticipated in the rule. The reason this came up in the first place is because my partner and i are just starting to merge canape bidding into our weak Nt/precision bidding system. It would potentially be convenient for us to have a variable NT range, independently legal, dpending upon the heart holding. All the discussions and the rule dont seem to give the mutual exclusivity any bearing, probabky because no one (few)ever have considered it.

[Shugart23]

Forgot to add, because of the exclusivity, they are not consecutive or non consecutive ranges. They are indeoendent if one another

[kenrexford]

I thought the who nonconsecutive range issue was for Woodson. I thought Woodson was a two-way 1NT showing either 10-12 or 16-18, or something like that, with some call like 2C used to determine which. I thought each of the two ranges had to be tight, like described. I may be completely wrong, but that's what I thought.

 

Assuming my assumptions, it would be somewhat silly to allow 10-12 or 14-16, but then to disallow 10-12 or 13-15. In that context, if the question posed were, "Is this a ruse to allow a 6-point range or a true two-way approach?", then I understand the heart-no-hearts reasoning. There is a structural reason for the nuance, not a ruse reason.

 

In a strong club system with 4-card majors, a 1H opening gives more space than a 1S opening. In a very simplistic example, 1H...1NT is possible, but no parallel after opening 1S. Thus, Opener has a better auction if balanced with hearts but not if balanced without hearts.

 

This reality suggests a solution for system purity, obscure though it might be to understand, where this nuanced 1NT, intended as two-way, makes bridge sense.

 

Thus, if somehow the non-consecutive ranges issue were what I thought, the heart holding is not pure gibberish but rather justified by bridge logic.

[Vampyr]

That is a pretty good interpretation of the rule (and almost convincing), but by your interpretation, 1NT =10-11 OR 19-20 is allowed because there are only 4 possible values...But we know this is not true, so your interpretation ( "the range is the possible values it might be")is not right.

 

 

Who knows this isn't true?

 

 

What we all can agree on is that either having 4 hearts or not having 4 hearts are two mutually exclusive events. And we can all agree that 10-13 is a 4 point range and having 14-17 is a 4 point range. We all can agree that if I always open 1NT promising 4 hearts and 10-13 HCP, that this would be allowed...We also can agree if I always open 1NT denying 4+Hearts and 14-17 HCP that this would also be allowed.

 

The overwhelming interpretation of the rule is that combining these two mutually exclusive events somehow means I would be opening a hand that has a wide 10-17 HCP range, which is definitely not the case...Every hand that would opened one NT would have a very specific 4 point range due to the mutually exclusiveness of the two cases (Hearts or no Hearts) and then on the rebid, everyone at the table finds out which case it is..10-13 or 14-17.

 

The rule doesn't say the Opponents have to know what the range is immediately; this is an interpretation of the rule The rule simply says the range has to be less than 5 (which it always will be) and , elsewhere,that the Opponents are entitled to know what the partnership agreement is.

 

Clearly I have way too much time on my hands and need to focus instead on rooting for the Packers....

 

Your idea might work online, where you could tell both opponents, but not partner, how many hearts you held. But in live bridge, this amount of UI would obviously be unacceptable.

[Shugart23]

No. I wouldnt tell anybody how many hearts I held. That wiuld be gkeaned by evetyone at tbe table on my rebid. Here is the closest analogy i can come uo with. I live on 25 elm street. You live on 27 elm street. Someone else lives on 29 elm street. We are all on the same block. Someone else lives on 31 spruce street. The soruce street occupants have nothing to do with the elm street occupants