BidBase Hand
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Zar gives no points for intermediates. After examining other systems, we are inclined towards .5 for T [B1770] and .25 for 9 [B1775]. COBRA gives T only .25, but that is on a 4321 HCP scale.
In keeping with Zar's adjustment for the Jack [B1650], we will not add this adjustment if either opponent has bid the suit. |
C1070 Doubleton Honor-Jack
| COBRA deducts for any short honors. Zar deducts for unprotected honors in the opponent's suit, but actually upgrades them when in partner's suit. |
C1060 No Aces
| This is a reasonable adjustment for 4321 HCPs, but Zar uses 6421 points, so the point penalty for not having an ace is already built into that count. |
C1110-1180 Biddable Suits
| Covered in B1580, B1590, and B1720-1745. |
C1190-1270 Short suit adjustments
| We feel like these are probably covered by Zar's suit length adjustments, although not exactly in the same way. It's possible that we are missing something here, but can't really tell. |
C1280-1490 Various adjustments for the bidding
| Again, these are covered by Zar, although not exactly the same way. Are the COBRA adjustments better or worse than Zar's? We can't say. |
C1520-1570 Various opening positions
| B1800-1850: We have accepted these on faith in COBRA's extensive computer analysis and put them into the entry numbers shown. |
C1500-1510 Long, running side suit
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As previously mentioned, Zar counts long suits in its own way, but it doesn't really count any extra for a long running side suit. COBRA gives 2 points for a running 6-card suit and 4 for a running 7+ card suit.
Whether a running side suit is actually worth anything depends on factors such as transportation (can you get to it to run it), other controls (doesn't help if you go set before running your suit), trump length (can't draw opponents' trumps), etc. With all of this going on, we don't feel right just giving such a suit points without having a handle on these other factors. If we are wrong about this, we would appreciate getting views to the contrary. |
KNR Points
KNR uses an initial 3-2-1 valuation for A-K-Q and counts short suits with standard 3-2-1 values.
KNR then uses a combination of honor points adjustment and distribution adjustment by adding more points for honors based on 4-3-2-1 HCP values multiplied by suit length, divided by 10.
In KNR, Ax is worth a total of 3.8 (3 + 4*2/10) while Axxxxx is worth 5.4 points (3 + 4*6/10).
Beyond that, we don't see anything in KNR that isn't covered in other ways in Zar.
KNR does not take bidding into account, so it is mainly of use for evaluating hands for opening bids.
TSP
TSP uses a 6421 honor valuation and 531 short suit valuation. It makes some adjustments for partner's bidding, but not the opponents'.
As such, it is suitable for valuing opener's hand and responder's hand in unopposed bidding.
BidBase Adjustments
We spent a lot of time researching existing hand evaluation systems, then more time writing this program, so we haven't gotten into researching for new hand valuation adjustments. When we do, this section will document our new adjustments.
Here is our only entry so far:
B1795 -- A suit headed by KQJT is only worth 6 HCPs, yet Stephen Levy says that this 16-HCP hand, 
A2 
QT9 
KQJT2 
AT2, is too strong to open 1NT because "the KQJT are worth more than 6 HCPs." (He instead opens 1D and then jump-rebids 2NT to show 18-19 HCPs.)
Likewise, in Dec.2005 Bridge World, page 20, the aceless, dead-flat, 12-HCP hand K93 KT4 KQJT T64 is opened by 21 of 25 expert panelists because KQJT is such a "robust suit".
Based on a study of hands like these, and just comparing two supposedly 6-VP holdings -- A432 and KQJT -- it is clear that KQJT is undervalued and so 2 evaluation points are added in BidBase for the KQJT holding.
B1860-1863 -- This came up on rec.games.bridge:
- South has QT42-J43-3-KQT85.
- His LHO opens 1S,
- pard overcalls 2H, P-P,
- then LHO reopens 3D, P-P to South.
BidBase/Zar, COBRA, and TSP (all the systems which consider other players' bids) put this hand within a King of game, because of the good clubs, the Tens, the honor in pard's trumps, and the singleton in LHO's 2nd suit. (BTW, everyone agrees that South should have raised or bid something the first time.)
The problem is that when South is dummy and RHO is short in LHO's suit, the play may start with a lead to LHO's A-K followed by a ruff by RHO. Losing 3 off the top is not a good start for making 4H.
The question is whether to downgrade South when his partner is likely to be declarer if he bids on and when South has:
- (B1860) length in LHO's suit without A or KQ,
- (B1861) RHO has not raised LHO, and
- (B1862) Pard has not shown shortness in the suit.
(Notice that B1861 could be done away with simply by putting its Hands spec in B1860, but giving it a separate entry makes following the computation easier.)
The next question is how much to adjust. Since the odds are high in this situation of losing a trick to a ruff, a 3-point deduction seems in order, but this is just gut. I don't have any science for it, nor is it 100% that a deduction of any kind is valid to start with. When BidBase Bidder is completed, it will be able to analyze such situations, but until then, we will use -3.
Zar says of B1665-1670:
This upgrade actually takes care of the value added by having your honors "in combinations" rather than being scattered around the 4 suits.
It seems unlikely that he intended this to apply when one of the suits is in a singleton, or even a doubleton, such as 5432-K-KJ2-AKQT2. In fact, the stiff K is actually a downgrade.
So while we left the Zar specs alone, we added entry B1660 to BidBase to make sure that the hand doesn't have a singleton or doubleton honor.
Calculations
BidBase points required for various bids and games:
- Open 1 of a suit = 26
- Respond 1/1 = 16
- Respond 2/1 (not GF) or limit raise = 21
- 2C Strong = 43
- Major game = 52
- Minor game or to explore for slam = 57
- Small slam = 62
- Grand slam = 67
Chart showing calculations:
