Analysis of Beta 1-level Openings

     
1st & 2nd position opening  requirements are in order of preference:

1S:         10+ HCP   Requires 5+ card suit upper limit is either our 2S opening: a strict 4-5LTC count and some shape requirements OR our 2D multi opening balanced with 19-20 HCP or 2N balanced 21-22HCP or 2C unbalanced <4LTC
1Sbis:    4-7LTC     Requires 5+ Spades & 5+ Clubs: Requires mandatory rebid of 3C WITH or WITHOUT jump.
1Sbis:    A 3rd Hand opening is 4+ cards & HCP may be  < 10 with distributional compensation.
1H:        10+ HCP   as for 1S above.
1Hbis:   10+ HCP  Requires precisely 4-4 in Majors. Upper limit is 18HCP. our 2D  multi covers 19-20 & 2N 21-22 or 2C: 23+ 1Hbis:   This includes 44{41} hands too - rebid when NO Major fit discovered should be the then in the 3rd suit
1Hbis:   1H opening and a 3C rebid is natural BUT denies a 5-5+ hand
1D:        (11)12+ HCP   Requires 5+ card suit. Balanced hands limited to 12-16  NT rebid & 2N rebid 17-18. Unbalanced hands <4LTC limited by a 2C opening. Note can only be opened safely with (10-11) HCP when a clear cut rebid is available - i.e. rebid with 6+ cards OR a new suit holding a 5-4 distribution.
1Dbis:    4-7LTC    Requires 5+ Diamonds & 5+ Clubs: Requires a mandatory rebid in Clubs at the 3+ level with or without a jump. (Same as with Spades above). However 
1N:        12-14 HCP Balanced. Further shape constraints: 7-9minor cards, 3card minimum in each miner with a top honour. Also Not suitable for any of the above openings 
1C:        12+ HCP   Strictly unsuitable for a 1N opening or any over listed above.
1Cbis:     This is the most frequent of all opening bids so it deserves some mention! It describes a hand strictly unsuitable for any other system opening bid and partner must bear this fact in mind in subsequent bidding.
PASS:    0-11 Be prepared to PASS unless suitable for any of our openings
With a 6 card Major and weak open 2D;
With a 7 card Major consider a 3+Ma pre-empt;
With a (7)8+ card minor suit consider a 3N gamble or a 4+ mi pre-emptive opening. Note BETA does NOT have 3mi pre-emptive openings


1NT opening is an adjusted 12-14. Lower for flat 4333 or being Aceless or for 3+ Jacks. Augment with 2+ Aces or a good (useful)  9's and 10's significantly supporting higher honours!
Minimum 1C|D openings that lack either a 4 card Major or are Aceless unless containing a 6+ card minor which allowing a rebid of 2mi.
1suit openings should be adjusted -1 HCP when Aceless.

Aproximate Frequency of the 1-level Beta opening bids are roughly as follows:

1C:    15.5%
1D:    8%
1H:    7.5%
1S:     7%
1N:    5%

Total for 1-level openings is: 43%

Average frequencies for Beta 2-level openings are (wider variations occur):

2C:    2.25%             23+ HCP and balanced - 2|3NT rebids OR unbalanced hands 5+ card suit and <=3.5 LTC. However 5-5+ hands are NOT opened by 2C - as 2C sequences are NOT designed for 5-5+ hands
2D:    4.5%               Includes weak Major 2's
2Ma:  3.25% each     Requires a strict LTC  count of <= 5LTC
2N:    1.75%

Total for 2-level openings is: 15%

Other openings: (considerable larger variations can occur)

PASS:        36%
3mi:            2%
Pre-empts:  2.5%        includes 3Ma, 3N, 4mi
4Ma:          1.5%         distributional bids with 7+ card Major NOT 7222!

Toatal Others: 42%

 Actually as Beta has evolved the % of an opening PASS bid  has dropped somewhat and a 1C opening has become more frequent.

Alertable Openings
 
1C!     alertable as it can be just 2 cards. In principal is forcing but Majorless near Yarboroughs can be passed
2C!     alertable as a near game bid. Also strictly forcing
2D!     multi is alertable 3-way - excepionnaly can be passed or raised ro 3D1 by a partner holding a 6+ card Diamond suit. Also  bid of 3C (a break-out)
2Ma!   alertable 4-5 LTC
3mi!     are alertable as 5-5+ or better in RED or MAJOR suits 4-7LTC

Principals behind responder's continuations to opening bids:

Direct 4 card support to Major openings must be shown immediately
Over 1C, 1D and 1Heart openings showing a major of 4+ cards  is a priority -  with both show the Hearts first regardless of length!
1C is forcing if any major showing response is available. 1N is a negative response denying any Major (PASS if RHO bids usually denies Majors) and * would show the presence of an unbid Major
If 1N is doubled, Responder bvids PASS|redouble which a are transfers for Clubs  or Diamonds respectively.

Beta handles interference bids by opponents in the following ways:
With support for partner - competitive raises,
Trustcott like: 2N over intervention showing support and values to compete soundly at at least  the 3-level.

Negative Doubles: Below game deny a fit in partner's suit & suggests interest in unbid suits. Opener is free to choose:  rebid (6 cards), bid a second suit, make a limit bid in NT's. This is typical of our usage of  'Negative Doubles'. Which also operate over higher level interventions too but are not usually suggestive of penalties unless following a weak jump o'call. However negative doubles will always promise minimum values as follows: At 1-level 8+, 2-level 10+, 3-level 12+ HCP and support for at least 2 possible suitrs(.
Also PASS may be the only bid available in Beta with substancial values|length in the opponents suit - relying on partner to re-open with a double!
Please note that doubles in 1C sequences are not Negative! - but usually signalling a specific Major holding.

If opponents open the bidding. Its a different scene altogether in Beta!
Holding 2 5 card suits see our comprehensive means to show both suits in one bid, A T-O * is another weapon of importance, our multi 1NT overcall handles other possibilities, and simple o'calls are natural.usually 5 card, however may also be a 4 card Major....

In the cases of 1mi openings the basic sequences are all about locating Major fits:  4-4 5-3 or 6-2! A major piece of the armoury is a wide ranging NT rebid (12-16) by the opener & Partners 2C rebid shows 9+HCP. if a 4-4 fit has not been discovered in order to test a 5-3 fit through a 2C inquiry requiring a 9+HCP count or direct rebis with 6 cards. See 1C & 1D details.
In the case of a 1H opening a direct fit in hearts must be shown when holding 4+ cards, otherwise 1S must be bid if 4+ cards are held. See details in 1H opening.

A weak partner with a (6)7+ card minor suit and NO Major suit can bid a minor break-out by jumping to the 3-level!
Corollary: Beta does not make jumps in new suits as responder to show force!  A 2-level bid or simply a change of suit is to be considered forcing.

For full details with all other possible responses see: our opening bids.