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Opening Bid Comparisons

by Richard Pavlicek

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.

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	any	376	1	808	49.60	Pass	821	50.40
First	any	605	1	1592	55.30	Pass	1287	44.70
First	any	242	1	693	61.49	Pass	434	38.51
First	any	231	1	617	51.94	Pass	571	48.06
First	any	188	1 NT	465	53.82	Pass	399	46.18
Second	any	153	1	404	61.59	Pass	252	38.41
Second	any	280	1	731	57.70	Pass	536	42.30
Second	any	133	1	266	40.00	Pass	399	60.00
Second	any	88	1	193	48.13	Pass	208	51.87
Second	any	83	1 NT	174	55.06	Pass	142	44.94
Third	any	107	1	239	59.60	Pass	162	40.40
Third	any	164	1	341	55.63	Pass	272	44.37
Third	any	92	1	156	37.41	Pass	261	62.59
Third	any	76	1	154	50.00	Pass	154	50.00
Third	any	9	1 NT	28	66.67	Pass	14	33.33

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	10-11	122	1	251	54.33	1	211	45.67
First	12-13	659	1	1270	54.13	1	1076	45.87
First	14-15	126	1	226	43.71	1	291	56.29
First	16-17	122	1	333	60.00	1	222	40.00
Second	10-11	73	1	124	47.51	1	137	52.49
Second	12-13	349	1	697	51.52	1	656	48.48
Second	14-15	102	1	227	57.04	1	171	42.96
Second	16-17	77	1	134	41.49	1	189	58.51
Third	10-11	38	1	94	81.03	1	22	18.97
Third	12-13	154	1	295	53.15	1	260	46.85
Third	14-15	57	1	153	66.23	1	78	33.77
Third	16-17	33	1	93	54.71	1	77	45.29

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	10-13	350	1	628	44.04	1 NT	798	55.96
First	14-15	423	1	882	52.22	1 NT	807	47.78
First	16-17	318	1	660	59.35	1 NT	452	40.65
Second	10-13	180	1	304	47.20	1 NT	340	52.80
Second	14-15	248	1	446	47.00	1 NT	503	53.00
Second	16-17	227	1	493	56.21	1 NT	384	43.79
Third	10-13	40	1	59	38.06	1 NT	96	61.94
Third	14-15	138	1	244	48.41	1 NT	260	51.59
Third	16-17	132	1	228	47.40	1 NT	253	52.60

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	10-13	386	1	732	44.58	1 NT	910	55.42
First	14-15	307	1	584	45.88	1 NT	689	54.12
First	16-17	66	1	127	47.39	1 NT	141	52.61
Second	10-13	156	1	284	48.22	1 NT	305	51.78
Second	14-15	185	1	263	40.34	1 NT	389	59.66
Second	16-17	53	1	115	51.57	1 NT	108	48.43
Third	10-13	60	1	112	50.68	1 NT	109	49.32
Third	14-15	90	1	151	47.63	1 NT	166	52.37
Third	16-17	29	1	56	40.88	1 NT	81	59.12

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	10-13	64	1	88	36.07	1 NT	156	63.93
First	14-15	114	1	203	46.67	1 NT	232	53.33
First	16-17	21	1	29	43.94	1 NT	37	56.06
Second	10-13	28	1	69	43.40	1 NT	90	56.60
Second	14-15	71	1	109	36.31	1 NT	192	63.79
Second	16-17	18	1	33	66.00	1 NT	17	34.00
Third	10-13	16	1	32	62.75	1 NT	19	37.25
Third	14-15	32	1	57	52.29	1 NT	52	47.71
Third	16-17	10	1	38	61.29	1 NT	24	38.71

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	10-13	39	1	91	61.07	1 NT	58	38.93
First	14-15	70	1	150	57.03	1 NT	113	42.97
First	16-17	22	1	17	30.36	1 NT	39	69.64
Second	10-13	26	1	69	75.00	1 NT	23	25.00
Second	14-15	40	1	61	38.85	1 NT	96	61.15
Second	16-17	15	1	53	70.67	1 NT	22	29.33
Third	10-13	12	1	19	43.18	1 NT	25	56.82
Third	14-15	17	1	25	55.56	1 NT	20	44.44
Third	16-17	12	1	18	50.00	1 NT	18	50.00

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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. In second suit 2 NT fared better than any suit opening, but in first and third it’s a mixed bag.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	any	165	1	360	50.21	2 NT	357	49.79
First	any	43	1	84	35.15	2 NT	155	64.85
First	any	10	1	20	83.33	2 NT	4	16.67
First	any	11	1	25	58.14	2 NT	18	41.86
Second	any	111	1	127	29.40	2 NT	305	70.60
Second	any	15	1	37	48.05	2 NT	40	51.95
Second	any	9	1	13	20.97	2 NT	49	79.03
Second	any	7	1	2	40.00	2 NT	3	60.00
Third	any	77	1	111	45.31	2 NT	134	54.69
Third	any	15	1	43	61.43	2 NT	27	38.57
Third	any	6	1	13	61.90	2 NT	8	38.10
Third	any	4	1	1	33.33	2 NT	2	66.67

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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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	16+	132	1	274	50.46	2	269	49.54
First	16+	12	1	5	7.35	2	63	92.65
First	16+	6	1	24	50.00	2	24	50.00
First	16+	14	1	58	65.91	2	30	34.09
Second	16+	85	1	160	36.61	2	277	63.39
Second	16+	12	1	23	21.30	2	85	78.70
Second	16+	6	1	3	15.00	2	17	85.00
Second	16+	10	1	1	2.56	2	38	97.44
Third	16+	72	1	112	32.56	2	232	67.44
Third	16+	5	1	24	60.00	2	16	40.00
Third	16+	1	1	0	0	2	17	100
Third	16+	10	1	29	44.62	2	36	55.38

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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 based on system (Standard vs. Precision) since the 9-15 HCP range precludes strong hands.

In the other three suits the choice was typically between a light one-bid and a weak two-bid, but the auctions are not individually screened, so various anomalies slip through such as two-suited two-bids (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.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	9-15	312	1	702	46.99	2	792	53.01
First	9-15	75	1	171	58.76	2	120	41.24
First	9-15	177	1	311	41.80	2	433	58.20
First	9-15	138	1	250	44.56	2	311	55.44
Second	9-15	150	1	379	52.20	2	347	47.80
Second	9-15	27	1	52	34.67	2	98	65.33
Second	9-15	82	1	127	41.37	2	180	58.63
Second	9-15	63	1	160	56.34	2	124	43.66
Third	9-15	57	1	68	29.44	2	163	70.56
Third	9-15	18	1	30	36.59	2	52	63.41
Third	9-15	50	1	102	38.49	2	163	61.51
Third	9-15	25	1	48	54.55	2	40	45.45

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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. Except for the cases in second seat, preempts show a profit. Data is sparse, however, so it’s too early to bet the farm.

Seat	HCP	Cases	Table 1	IMPs	Percent	Table 2	IMPs	Percent
First	any	29	1	53	33.33	4	106	66.67
First	any	29	1	51	35.92	4	91	64.08
Second	any	7	1	17	89.47	4	2	10.53
Second	any	8	1	25	80.65	4	6	19.35
Third	any	7	1	8	16.67	4	40	83.33
Third	any	14	1	33	47.14	4	37	52.86

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© 2014 Richard Pavlicek