Scream vs IMPrecision vs straw man

[awm]

I'm thinking about....

 

1C-1D,

.....1H-H various or 17+ balanced

.....1S-S/m or 5S bal

.....1N-H/S

 

Now we have to rebid 2N with 21-22 or so.

 

What do you think of this tradeoff?

 

Well the disadvantages are small: (1) I do like bidding 1NT on the big hands, both for safety and because I can invite in a minor and stuff (2) You still lose responder's natural DN 2♠ sometimes. (3) There are still some issues when opener has a really big hand with hearts opposite a balanced GF, since opener cannot make a NF 2♦/2♥ call.

 

The advantages are small too though: (1) Removing balanced with four spades from 1♠ helps a little on relays, but you're still usually +1. (2) It is a little easier to bid three-suiters with both majors by starting with 1N.

 

The main point is that you seem to think it is a very substantial win to play relays at +2 with relayer's hand being unknown, rather than to play notrump "systems on" over a natural and limited 1NT bid. I do not agree with this, and think it is at best a wash and quite possibly actually better to play notrump "systems on" in this situation.

[straube]

I looked at frequency rebids after 1C-1D for 58 hands. Fibonnaci isn't everything, but I think it's a good indicator. Something looks out of kilter with both methods, but I'm still interested in rebidding 1H with the balanced hands.

 

 

1H as bal or hearts.........57%................1H as bigger or hearts...........17%

1S natural.......................24%................1S natural..............................30%

1N as majors...................7%.................1N as 17-20..........................40%

2C as natural...................7%.................2C as natural...........................7%

2D as natural...................3%.................2D as natural...........................3%

other................................1%.................other.......................................1%

[straube]

I'm thinking we're at +2 for most 2-suited hands, but we're only +1 for the 1-suited hands and for C/D. Hopefully, when responder has a major, we will have a fit and have extra room to relay on the way to 4M.

 

1C-1D, 1H

 

1N-4+ hearts

.....2D-4+ spades at +2

..........2S-3-suited, short minor at +2

.....2H-4+ clubs at +2

.....2S-single-suited at +1 (no 5332)

2C-4+ spades at +2

2D-C/D at +1

2H-C at +1

2S-3-suited, short major at +1

etc-D at +1

[awm]

I looked at frequency rebids after 1C-1D for 58 hands. Fibonnaci isn't everything, but I think it's a good indicator. Something looks out of kilter with both methods, but I'm still interested in rebidding 1H with the balanced hands.

 

 

1H as bal or hearts.........57%................1H as bigger or hearts...........17%

1S natural.......................24%................1S natural..............................30%

1N as majors...................7%.................1N as 17-20..........................40%

2C as natural...................7%.................2C as natural...........................7%

2D as natural...................3%.................2D as natural...........................3%

other................................1%.................other.......................................1%

 

I disbelieve these statistics. To see that they are wrong, consider that virtually every hand that rebids 1♠ would rebid 1♥ with the majors reversed (small number of exceptions like 5/5 majors and 4M-5♣) so the odds of 1♠ rebid cannot be this much higher than 1♥ rebid. Here are my stats for IMPrecision rebids after 1♣-1♦:

 

1♥: 25.8%

1♠: 27.0%

1N: 29.3%

2♣: 9.4%

2♦: 6.0%

other: 2.5%

 

The Fibonacci thing doesn't really apply here, because the relay over both 1♥ and 1♠ is 1NT so you want equal space to resolve. Also, we are not normally relaying out opener's shape after the 1NT rebid (plus the number of patterns in 1NT is actually rather small and further they are patterns that tend to play similarly, it's just that balanced hands are very frequent).

[straube]

I may have tabulated some hands wrong and I only looked at fifty-some, but thanks for the true figures. Here's what I got for the 2 methods after 1C-1D, 1H. If you have better statistics I would be interested to know them. Results are in hands and there are more for the tweak because more 1H rebids.

 

IMPrecision

 

1S- 12

1N-17

2C-1

2D-0

2H-1

2S-1

 

tweak

 

1S- 56 hands

1N-5

2C-4

2D-2

2H-1

2S-2

[straube]

I think I give up. I like the branching IMPrecision gets after 1C-1D and I also like the branching it gets at 1C-1D, 1H. I still have the idea to use 1C-1D, 1H-2L for some relays, but responder bidding 1N to establish a GF with usually a balanced hand makes a lot of sense to me. Thanks for putting up with me and I've really enjoyed the IMPrecision notes.

[Zelandakh]

ok, so putting these side by side. IMPrecision is guesstimated and generic symmetric 1D response is 0-7 and 1H response is all of the S+ hands and 1S is all of the balanced and both minor hands....

 

.....................Fibonacci.............SCREAM...............IMPrecision.................straw man.................generic symmetric 1D=0-7

1D...................41.......................36........................37..............................28.............................57

1H...................25.......................41........................24..............................41.............................14

1S...................16.......................16........................22..............................20.............................20

1N....................9.........................1.........................12...............................4..............................4

other................9.........................6..........................6................................7..............................5

 

Again, not saying Fibonacci is everything...other considerations like which sequences are most important plus one would expect to spend more room than Fibonacci would suggest because one's other goal is to take up space before the opponents do.

Did you notice on this graph that if you switch the 1♦ and 1♥ response in "straw man" you get something almost exactly like your Fibonacci numbers? I am not saying this ia a good idea, just an interesting observation.