BBO Discussion Forums: How do you scan this hand? - BBO Discussion Forums

Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

How do you scan this hand?

#1 User is offline   Nirmalya 

  • PipPip
  • Group: Members
  • Posts: 30
  • Joined: 2012-October-26

Posted 2013-April-24, 00:04

I have been following posts on Spiral Scan, DCB, QP, CP et all. Not yet sure whether I should fancy trying some of these. I have recently come accross this hand
South opens 1C Precision


Lets assume you have found out the distribution, and strength of your partner by whatever relay method you use and whatever QP/CP you play. All I need to know is whether my Partner has the !DK and !SA or not. I have not come accross a scanning method which clearly places !SA (and NOT THE !SK) with my partner. Incidentally, !DK is easy to place as I have the other honors.

May be I have not understood the finer points od Spiral Scan as yet. Some of you may help me here.
0

#2 User is offline   wclass___ 

  • PipPipPipPip
  • Group: Full Members
  • Posts: 431
  • Joined: 2008-November-02

Posted 2013-April-24, 00:42

If you have information that partner has 3 controls then once you get to know he has control in and , but not in other suits there is only one possibility how you can get 3 controls and it is:

K and A.
Seeking input from anyone who doesn't frequently "wtp", "Lol" or post to merely "Agree with ..." --sathyab
0

#3 User is offline   Zelandakh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,738
  • Joined: 2006-May-18
  • Gender:Not Telling

Posted 2013-April-24, 01:52

It is certainly true that the honour structure can be ambiguous in some of the popular scanning methods, particularly the multi-way QP methods. For CPs and DCBs, ambiguity should generally only come on hands where you do not want to be in slam. Let us take an example CP auction and assume that North's last bid was 3NT having shown 3325 shape and 3 controls. Then

4 = relay
... - 4 = no club control
4 = relay
... - 4NT = spade control, no heart control
5 = relay
... - 5 = diamond control, no Q

As you can see, we now know that partner has A and K. We can also look at a possible Spiral Scan continuation.

4 = relay
... - 4 = no A
4 = relay
... - 4NT = A, no K
5 = relay
... - 5 = no K
5 = relay
... - 5 = no K

Again, we now know that North has A and K.

For QPs, let's assume that North has shown the 3325 shape with 5QPs with a 3NT bid. Now if South continues in relays, it might continue
4 = relay
... - 4 = 0 or 2 from AKQ
4 = relay
... - 4NT = 1 or 3 from AKQ, 0 or 2 from AKQ
5 = relay
... - 5 = 1 or 3 from AKQ

and now we can again place North with A and K, but here there is the additional information that North does not hold an additional queen. This is what makes the QP method powerful. You allow for an occasional ambiguous hand but gain more information for the space used most of the time. It does require a fair amount of mental agility to get the most out of. Hopefully, these examples have at least helped a little.
(-: Zel :-)
0

#4 User is offline   Nirmalya 

  • PipPip
  • Group: Members
  • Posts: 30
  • Joined: 2012-October-26

Posted 2013-April-24, 01:53

View Postwclass___, on 2013-April-24, 00:42, said:

If you have information that partner has 3 controls then once you get to know he has control in and , but not in other suits there is only one possibility how you can get 3 controls and it is:

K and A.


Thanks for such a prompt reply.
OK, that is clear. However, do you find out exact controls? I mean exact controls like 0-1/2/3/4/5/6/7 .... Like that
If we try to find the exact number of controls, by strep responses for example, the bidding may reach very high level even before a scan is started. Please educate me on this subject a little more
Thanks
0

#5 User is offline   Zelandakh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,738
  • Joined: 2006-May-18
  • Gender:Not Telling

Posted 2013-April-24, 02:01

It is normal to have a step for controls after full shape is shown. For my system (using CPs), the scale for a minimum GF over a 1 opening is: 0-1/2/3/4+zoom. More than 4 controls are not possible since 5+ controls are automatically not a minimum. If I remember correctly, Adam (using QPs) has a scale something like: 0-3/4/5/etc. That is a downside of QPs - you sometimes need to eat up more space showing controls than for CPs since the variance is higher.
(-: Zel :-)
0

#6 User is offline   wclass___ 

  • PipPipPipPip
  • Group: Full Members
  • Posts: 431
  • Joined: 2008-November-02

Posted 2013-April-24, 02:24

View PostNirmalya, on 2013-April-24, 01:53, said:

If we try to find the exact number of controls, by strep responses for example, the bidding may reach very high level even before a scan is started.


Getting exact shape as low as possible is very crucial for this type of scheme to work, thankfully there are lot of tricks how to optimize such a structure.

Personally I feel comfortable if 3 or maximum 3 shows exact shape. I wouldn't play such relays if I have to ask for controls with 4 or higher bid.
Seeking input from anyone who doesn't frequently "wtp", "Lol" or post to merely "Agree with ..." --sathyab
0

#7 User is offline   rhm 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,092
  • Joined: 2005-June-27

Posted 2013-April-24, 03:13

View PostNirmalya, on 2013-April-24, 00:04, said:

I have been following posts on Spiral Scan, DCB, QP, CP et all. Not yet sure whether I should fancy trying some of these. I have recently come accross this hand
South opens 1C Precision


Lets assume you have found out the distribution, and strength of your partner by whatever relay method you use and whatever QP/CP you play. All I need to know is whether my Partner has the !DK and !SA or not. I have not come accross a scanning method which clearly places !SA (and NOT THE !SK) with my partner. Incidentally, !DK is easy to place as I have the other honors.

May be I have not understood the finer points od Spiral Scan as yet. Some of you may help me here.


Interesting hand for Polish club too.

The way I play the bidding might go

1--1
1--1NT*
2**--2
3--4***
4--6

* = wide ranging, maximum is a poor ten count
** = 18+, at least 4 diamonds, at least 8 cards in spades and diamonds
*** = Minorwood

Rainer Herrmann
0

#8 User is offline   rbforster 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,611
  • Joined: 2006-March-18

Posted 2013-April-24, 06:42

I will point out that QPs and similar methods are poorly suited when opener has a small singleton you often be unable to make sense of what values may or may not be wasted in his suit. For this reason many relay players also include the option to ask Roman Keycard Blackwood. In my methods,

1...3 GF 3325 shape by responder
3-3N 1430 RKC; 1/4 (3 would have asked for QPs)
4-4 spade ask; A or KQ (4 would have been trump Q ask)
4N-5 diamond ask; K or AQ (4 would have been ask in hearts, not needed. A 5 reply would have been no diamond honors)
6
0

#9 User is offline   Nirmalya 

  • PipPip
  • Group: Members
  • Posts: 30
  • Joined: 2012-October-26

Posted 2013-April-24, 07:16

View Postrbforster, on 2013-April-24, 06:42, said:

I will point out that QPs and similar methods are poorly suited when opener has a small singleton you often be unable to make sense of what values may or may not be wasted in his suit. For this reason many relay players also include the option to ask Roman Keycard Blackwood. In my methods,

1...3 GF 3325 shape by responder
3-3N 1430 RKC; 1/4 (3 would have asked for QPs)
4-4 spade ask; A or KQ (4 would have been trump Q ask)
4N-5 diamond ask; K or AQ (4 would have been ask in hearts, not needed. A 5 reply would have been no diamond honors)
6


Looks very neat indeed.
Can you let me have your full method pl? Like how would you reply to 3 QP ask?
Also, reply to 4NT ask is not fully understood. 5 would have showed no honor, so 5 should be Q or AK, 5 should be K or AQ and 5 should be A or KQ

I will wait for your response
0

#10 User is offline   Free 

  • mmm Duvel
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,728
  • Joined: 2003-July-30
  • Gender:Male
  • Location:Belgium
  • Interests:Duvel, Whisky

Posted 2013-April-24, 11:21

After exact shape and before scanning you need to know a certain count (controls, AKQ points,...), otherwise scanning is impossible to interpret. I've always used AKQ points (A=3, K=2, Q=1), so I'd know 5 AKQ points. After one scan I know everything: 1/2 top honors , 1/2 top honors and no other top honors. K is clear (= 2 AKQ points) so that leaves us with 3 AKQ points for . The only possibility is A, because we hold the Q making KQ impossible.

Staying low to know exact shape is indeed very important. Even more so with balanced hands, because you have 4 suits to scan! Note however that 5332's can also be scanned as 14-card hands. Assume you've shown a 5332 with the 5 card known. Step 1 asks for exact shape, but step 2 and higher can be used for immediate slam investigation assuming that you have a 5333 distribution. This keeps you much lower and is very useful when you have to ask about a balanced hand. Same goes for 4432's with known 4 card suits (assume 4433), 4333's with unknown 4 card (assume 3333), 6322 with known 6 card (assume 6222), 7321 with unknown 3-2 (assume 7331),... There are many 12 or 14 card distributions, something which can be very useful to stay a bit lower when exact shape is not extremely important.
"It may be rude to leave to go to the bathroom, but it's downright stupid to sit there and piss yourself" - blackshoe
0

#11 User is offline   rbforster 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,611
  • Joined: 2006-March-18

Posted 2013-April-24, 17:49

View PostNirmalya, on 2013-April-24, 07:16, said:

how would you reply to 3 QP ask?
Also, reply to 4NT ask is not fully understood. 5 would have showed no honor, so 5 should be Q or AK, 5 should be K or AQ and 5 should be A or KQ

After a 3 QP ask, we reply in steps <=6, 7, 8, .... Some people prefer to separate 5 from 6, or require 5 (or 6) QPs for a positive response and have HCP heavy but control poor hands start with a negative 1. I don't take that approach. We get more space on 7+ and more uncertainty with less.

The replies to a side suit control ask are (cheapest trump suit)= no control, otherwise steps A/KQ, Q/AK, K/AQ, AKQ. I mostly use Richard Willeys Moscito slam methods, although that document seems hard to find online these days. I'd read that, or you can read the summary I wrote up for myself but it may be a little less clear or I might have missed some things.

http://www.docin.com/p-125445669.html
http://www.its.calte...ge/seismic.html
0

#12 User is offline   Nirmalya 

  • PipPip
  • Group: Members
  • Posts: 30
  • Joined: 2012-October-26

Posted 2013-April-24, 22:26

View Postrbforster, on 2013-April-24, 17:49, said:

After a 3 QP ask, we reply in steps <=6, 7, 8, .... Some people prefer to separate 5 from 6, or require 5 (or 6) QPs for a positive response and have HCP heavy but control poor hands start with a negative 1. I don't take that approach. We get more space on 7+ and more uncertainty with less.

The replies to a side suit control ask are (cheapest trump suit)= no control, otherwise steps A/KQ, Q/AK, K/AQ, AKQ. I mostly use Richard Willeys Moscito slam methods, although that document seems hard to find online these days. I'd read that, or you can read the summary I wrote up for myself but it may be a little less clear or I might have missed some things.

http://www.docin.com/p-125445669.html
http://www.its.calte...ge/seismic.html


I have now gone through your notes. It was great, and really a big THANK YOU

Although I am sure that there must be some logic behind the chosen order of steps in side suit asking bids as A,Q,K and not in natural sequence (AKQ or QKA) I didn't quite understand it. Also when you have no honor in a side suit, partner's response will leave you in dark (for example Q or AK?)

Also, when you use RKC in this sequence, do you have any method for Exclusion RKC?
0

#13 User is offline   Fluffy 

  • World International Master without a clue
  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,404
  • Joined: 2003-November-13
  • Gender:Male
  • Location:madrid

Posted 2013-April-25, 02:43

Zel: at least in one of your examples you are making slam driving relays when small slam is the smallest target.

This one might be easier in natural:

1-1NT
3-3
0

#14 User is offline   Zelandakh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,738
  • Joined: 2006-May-18
  • Gender:Not Telling

Posted 2013-April-25, 03:05

View PostFluffy, on 2013-April-25, 02:43, said:

Zel: at least in one of your examples you are making slam driving relays when small slam is the smallest target.

The examples are to illustrate how the scanning process works, not meant as model auctions for how these hands should be bid. As it happens, my system does not even relay these hands since North is not a GF over a 15+ 1 opening (although relays will be an option once SPs are implemented, of course). On these hands, a perfect auction might be to break relays and set clubs as trumps at the 3 level, finding out that North has spade and diamond controls, and then using RKCB. It sounds like Free might have a system that can come close to achieving this.
(-: Zel :-)
0

#15 User is offline   rbforster 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,611
  • Joined: 2006-March-18

Posted 2013-April-25, 05:48

View PostNirmalya, on 2013-April-24, 22:26, said:

I have now gone through your notes. It was great, and really a big THANK YOU

Although I am sure that there must be some logic behind the chosen order of steps in side suit asking bids as A,Q,K and not in natural sequence (AKQ or QKA) I didn't quite understand it.

Glad it helped and youre welcome. as for logic, I mostly just copied what Richard had. My guess is that typically you have shortness when you don't have any honors and are still interested in side suit controls, in which case the first priority would be A (step 1 A/KQ), followed by AK (step 2, Q/AK). Said another way, most hands will use QPs and not RKC, so the use of RKC in slam relays is a bit more specialized than you might be used to from "normal bridge", and focuses on slams needing either filler for a running side suit or a side ace for first runs control of a weak or short side suit.

View PostNirmalya, on 2013-April-24, 22:26, said:

Also when you have no honor in a side suit, partner's response will leave you in dark (for example Q or AK?)

Also, when you use RKC in this sequence, do you have any method for Exclusion RKC?

Remember you should have a decent handle on the number of A's from your RKC answer. If that doesn't resolve which ace (such as where exactly one is missing), I think you should ask about the other side suit where partner might have an ace - I.e. when faced with a choice, ask in the suit where you have an honor so its clear. If you have no honors in either suit, well, maybe you aren't making slam anyway :).

As for X-RKC, I don't have methods to use it myself because I already find the basic RKC is relatively rare and I'm too lazy to add more structure at this point. However, if you want it's definitely possible to include it. See for example the 4 exclusion relay used by TOSR in their slam relays.

http://www.bantha.or...hk/bridge/tosr/
0

#16 User is offline   keylime 

  • PipPipPipPipPipPipPip
  • Group: FD TEAM
  • Posts: 2,735
  • Joined: 2003-February-13
  • Gender:Male
  • Location:Nashville, TN
  • Interests:Motorsports, cricket, disc golf, and of course - bridge. :-)

Posted 2013-April-26, 13:59

View PostNirmalya, on 2013-April-24, 00:04, said:

I have been following posts on Spiral Scan, DCB, QP, CP et all. Not yet sure whether I should fancy trying some of these. I have recently come accross this hand
South opens 1C Precision


Lets assume you have found out the distribution, and strength of your partner by whatever relay method you use and whatever QP/CP you play. All I need to know is whether my Partner has the !DK and !SA or not. I have not come accross a scanning method which clearly places !SA (and NOT THE !SK) with my partner. Incidentally, !DK is easy to place as I have the other honors.

May be I have not understood the finer points od Spiral Scan as yet. Some of you may help me here.


1C-2D* (balanced, 8 to bad 11)
3D* (SAB) - 3H* (2 diamonds)
4C* (SAB) - 4NT* (4 clubs, 3 controls)

So there's 8 controls, and you have no clue where they are. I'd rebid 5C and take a plus. Slam is really, really hard to get to. In non-relay Precision, you may actually get there.
"Champions aren't made in gyms, champions are made from something they have deep inside them - a desire, a dream, a vision. They have to have last-minute stamina, they have to be a little faster, they have to have the skill and the will. But the will must be stronger than the skill. " - M. Ali
0

#17 User is offline   benlessard 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,465
  • Joined: 2006-January-07
  • Location:Montreal Canada
  • Interests:All games. i really mean all of them.

Posted 2013-May-04, 08:21

im a bit late on this one.

In comedy club/ Chapi where we used spiral scan it will go like this

1D-1H
1S-1NT
2Nt-3C
3D (showing 18+ 3154)

followed by 3S RKC in clubs.

4C(3)

Here I see 2 paths

1st asking for the queen C of club

----4D (CQ ?)
4S(yes but no KD)----4NT ask for extras ?
5C (no)---pass

or asking for the K of S (implying that you hold both lenght in clubs and K of D)

----4S (K of S ?)
4Nt (no)---5C

I cant bid it in my system because the J of D is such a big card.

http://bridge.downag...P1HP1SP1NP2NP3C
From Psych "I mean, Gus and I never see eye-to-eye on work stuff.
For instance, he doesn't like being used as a human shield when we're being shot at.
I happen to think it's a very noble way to meet one's maker, especially for a guy like him.
Bottom line is we never let that difference of opinion interfere with anything."
0

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

3 User(s) are reading this topic
0 members, 3 guests, 0 anonymous users