Main   Study 9X00 by Richard Pavlicek

# Opening Bid Comparisons

This study compares opening-bid choices in 72 major events from 1996 to 2014. Source data consists of 40,069 deals (80,138 results) from vugraph archives of the Vanderbilt, Spingold, U.S. Championship and World Team Championship — widely considered to be the four strongest team events each year.
 Open Pass 1 1 1 1 NT 1 1 NT 1 1 NT 1 1 NT Suit 2 NT One 2 One Two One Four

The basic idea is to consider only cases where a hand was opened differently at one table than the other, then determine which of these two actions was the long-term winner. Results are broken down by table position (first, second or third seat) and HCP where appropriate. Results based on minimal data may be unreliable but otherwise should be meaningful, because all participants were experts, including the world’s best.

In this study the meaning of a bid is not considered, however, choices within the same comparison have a like relationship in the great majority of cases. For instance, if a hand is opened 1  at one table and 1 NT at the other, it is almost always a balanced hand with five hearts. Similarly, if a strong hand is opened 1  at one table and 2  at the other, it is invariably a big-club versus standard system.

The winning choice for each comparison is tinted gold to aid recognition. To view the actual deals for any comparison, click on the number in the Cases column. TopMain

## Open vs Pass

The following table compares cases where a hand was opened at Table 1 but passed at Table 2. Essentially this is an assessment of light opening bids, which are broken down by position and strain. (Fourth seat is ignored, as passouts were rare.)

The general picture is that opening light in a minor or notrump fares better than passing. In a major, however, this is true only in first seat, though the numbers for 1  are very close.

Most remarkable is that opening light in hearts scored 61+ percent in first suit, but in second or third seat it’s a complete turnaround favoring the pass. Go figure.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
Firstany3761 80849.60Pass82150.40
Firstany6051 159255.30Pass128744.70
Firstany2421 69361.49Pass43438.51
Firstany2311 61751.94Pass57148.06
Firstany1881 NT46553.82Pass39946.18
Second any1531 38758.99Pass26941.01
Second any2801 63049.72Pass63750.28
Second any1331 30045.11Pass36554.89
Second any881 17543.64Pass22656.36
Second any831 NT17053.80Pass14646.20
Thirdany1071 23959.60Pass16240.40
Thirdany1641 34155.63Pass27244.37
Thirdany921 15637.41Pass26162.59
Thirdany761 15450.00Pass15450.00
Thirdany91 NT2866.67Pass1433.33
TopMain

## One Club vs One Diamond

The following table compares cases where a hand was opened 1 at Table 1 and 1 at Table 2, subdivided by position and HCP range. In many cases this was dictated by system (e.g., nebulous 1  because 1  is strong) so it’s not clear whether this provides any useful evidence — but interesting nonetheless.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First10-111221 25154.331 21145.67
First12-136591 127054.131 107645.87
First14-151261 22643.711 29156.29
First16-171221 33360.001 22240.00
Second 10-11731 14053.641 12146.36
Second 12-133491 63546.931 71853.07
Second 14-151021 19950.001 19950.00
Second 16-17771 17353.561 15046.44
Third10-11381 9481.031 2218.97
Third12-131541 29553.151 26046.85
Third14-15571 15366.231 7833.77
Third16-17331 9354.711 7745.29
TopMain

## One Club vs One Notrump

The following table compares cases where a hand was opened 1 at Table 1 and 1 NT at Table 2, subdivided by position and HCP range. In most cases the differences relate to system, i.e., with balanced hands (and some nearly so) 1 NT would be routine if the range fits your system.

Results suggest that the weaker the hand, the more desirable it is to open 1 NT, with a few anomalies thrown in related to position. Party time for weak notrumpers? Maybe, but being in the opposite camp I’ll pass on hosting the occasion.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First10-133501 62844.041 NT79855.96
First14-154231 88252.221 NT80747.78
First16-173181 66059.351 NT45240.65
Second 10-131801 26641.301 NT37858.70
Second 14-152481 41844.051 NT53155.95
Second 16-172271 47854.501 NT39945.50
Third10-13401 5938.061 NT9661.94
Third14-151381 24448.411 NT26051.59
Third16-171321 22847.401 NT25352.60
TopMain

## One Diamond vs One Notrump

The following table compares cases where a hand was opened 1 at Table 1 and 1 NT at Table 2, subdivided by position and HCP range. Except for a few narrow losses, 1 NT has the clear edge.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First10-133861 73244.581 NT91055.42
First14-153071 58445.881 NT68954.12
First16-17661 12747.391 NT14152.61
Second 10-131561 24942.281 NT34057.72
Second 14-151851 33050.611 NT32249.39
Second 16-17531 11149.781 NT11250.22
Third10-13601 11250.681 NT10949.32
Third14-15901 15147.631 NT16652.37
Third16-17291 5640.881 NT8159.12
TopMain

## One Heart vs One Notrump

The following table compares cases where a hand was opened 1 at Table 1 and 1 NT at Table 2, subdivided by position and HCP range. Except for third seat (and the highest range in second suit) it follows the general expert consensus that balanced hands with five hearts are better opened 1 NT if in range. One reason is to avoid rebid problems, and another is to shut out a 1  overcall.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First10-13641 8836.071 NT15663.93
First14-151141 20346.671 NT23253.33
First16-17211 2943.941 NT3756.06
Second 10-13281 8955.971 NT7044.03
Second 14-15711 16454.491 NT13745.51
Second 16-17181 2346.001 NT2754.00
Third10-13161 3262.751 NT1937.25
Third14-15321 5752.291 NT5247.71
Third16-17101 3861.291 NT2438.71
TopMain

## One Spade vs One Notrump

The following table compares cases where a hand was opened 1 at Table 1 and 1 NT at Table 2, subdivided by position and HCP range. Unlike the previous scenario with hearts, opening 1  is the overall winner, though not without a few curious twists.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First10-13391 9161.071 NT5838.93
First14-15701 15057.031 NT11342.97
First16-17221 1730.361 NT3969.64
Second 10-13261 7379.351 NT1920.65
Second 14-15401 9963.061 NT5836.94
Second 16-17151 5370.671 NT2229.33
Third10-13121 1943.181 NT2556.82
Third14-15171 2555.561 NT2044.44
Third16-17121 1850.001 NT1850.00
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## One of Suit vs Two Notrump

The following table compares cases where a hand was opened one of a suit at Table 1, and 2 NT at Table 2. Typically this compares a staid one-bid with an aggressive 2 NT, usually based on a 5+ card suit to offset the high-card deficiency — except for 1 , which in most cases was strong and artificial (dictated by system) so not a useful comparison. Suit openings generally fare better, but inconsistent variations by position add a little mystery.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
Firstany1651 36050.212 NT35749.79
Firstany431 8435.152 NT15564.85
Firstany101 2083.332 NT416.67
Firstany111 2558.142 NT1841.86
Second any1111 17841.202 NT25458.80
Second any151 4558.442 NT3241.56
Second any91 4775.812 NT1524.19
Second any71 480.002 NT120.00
Thirdany771 11145.312 NT13454.69
Thirdany151 4361.432 NT2738.57
Thirdany61 1361.902 NT838.10
Thirdany41 133.332 NT266.67
TopMain

## One of Suit vs Two Clubs

The following table compares cases where a hand was opened one of a suit at Table 1, and 2 (strong) at Table 2. For 1 , 1  and 1  this is almost always a “borderline 2  opening” decided differently at the two tables. For 1 , however, the comparison is biased, because it also includes strong-club openings.

I was surprised to see 2 fare better than 1 (except for a narrow first-seat loss) as the reduced bidding space should be a disadvantage — or at least that’s the hype of most big-club advocates. The comparison isn’t fair, however, because when the two bids coincide the strength of 2  is more narrowly defined. No doubt 1  forcing would fare much better than one of a suit on the 16-21 HCP range.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First16-371321 27450.462 26949.54
First16-37121 57.352 6392.65
First16-3761 2450.002 2450.00
First16-37141 5865.912 3034.09
Second 16-37851 16938.672 26861.33
Second 16-37121 6358.332 4541.67
Second 16-3761 420.002 1680.00
Second 16-37101 1128.212 2871.79
Third16-37721 11232.562 23267.44
Third16-3751 2460.002 1640.00
Third16-3711 002 17100
Third16-37101 2944.622 3655.38
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## One vs Two of Suit

The following table compares cases where a hand was opened one of a suit at Table 1, and two of the same suit at Table 2. The choice between 1  and 2  is almost always a natural 1  vs. Precision 2 , since the 9-15 HCP range precludes strong hands.

For other suits the HCP range is reduced to 9-12, since the objective is to find cases where the choice was between a light one-bid and a weak two-bid. Even so, various anomalies slip through, such two-bids that show two-suiters, including 2  Flannery.

It is curious how position plays a significant role (except for hearts). Who would have thought that a natural 1  beats 2  only in second seat? Further, there is no consistency among the suits, as each has a unique pattern regarding position.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
First9-153121 70246.992 79253.01
First9-15751 17158.762 12041.24
First9-151771 31141.802 43358.20
First9-151381 25044.562 31155.44
Second 9-151501 36249.862 36450.14
Second 9-15271 5838.672 9261.33
Second 9-15821 15751.142 15048.86
Second 9-15631 11440.142 17059.86
Third9-15571 6829.442 16370.56
Third9-15181 3036.592 5263.41
Third9-15501 10238.492 16361.51
Third9-15251 4854.552 4045.45
TopMain

## One vs Four of Major

The following table compares cases where a hand was opened one of a major at Table 1, and four of the same major at Table 2, which obviously compares “going slow” versus preempting. In first and third seat, preempts show a big profit, but in second seat the edge is to go slow. The reason is obvious: With one opponent having passed, chances of competition are lessened, so the focus turns to accurate bidding (perhaps even slam with partner unpassed). Data is sparse, however, so it may be too early to bet the farm.

SeatHCPCasesTable 1IMPsPercentTable 2IMPsPercent
Firstany291 5333.334 10666.67
Firstany291 5135.924 9164.08
Second any71 210.534 1789.47
Second any81 311004 00
Thirdany71 816.674 4083.33
Thirdany141 3347.144 3752.86
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