Why is Mr. Mitchell so much favored on this side of the Atlantic over Mr. Howell? Is this a case of reverse xenophobia? Perhaps that would be xenophilia.
In fact, John Templeton Mitchell was born in Glasgow*, Scotland in 1854 while Edwin Cull Howell was born on Nantucket, MA in 1860. Both were fine whist players and devised the movements which bear their names for whist tournaments. For more details on the Howell movement, see my earlier blogs: Howell movement and Howell some more.
There really does seem to be a horror of Howell movements on this side of the Atlantic. I've never understood why, although I do realize that if you have a high proportion of infirm players, then you might run out of stationary tables.
The advantage of a Howell movement is that it produces one winner. It is also the best way to run a small event. But the single-winner advantage can be especially compelling. When Kim and I visited a bridge club in England a few years back (in Tenterden, Kent), they happened to be having their Ladies' and Gentlemens' championship. Yes, they were two separate events. They were very gracious and assured us that we would be able to play. The ladies event had about sixteen and a half tables so we were drafted in there. For me, it was the only time that I've played bridge where every other player in the event was of the opposite sex. But my point is that they used some sort of Howell movement, even though they had a large number of tables. Why? Because it produces one winner - very satisfactory for a championship. [We were sufficiently polite not to spoil things by winning of course].
Even at our current regional in Mansfield a few days ago, we were in a 5 table Mitchell for a side game. We played five rounds of five boards each. But that means there were four pairs (40%) we didn't play directly. A nine-round Howell would have worked perfectly.
But I do feel that a smallish two-session event should be done as a Howell in the second session. That's because randomness just doesn't mix the pairs up well for the second session. Take yesterday's Open pairs, for instance, with 10 tables. The first session was reasonably well mixed up, judging from the recap. But when the crossover occurred for the second session most of the contenders (in my subjective judgment) were sitting E/W. In fact the three top-placed pairs after one session all sat E/W in the second session. In the second session the N/S winners, who clearly played very well indeed, were able to score over 70% while the other scores ranged from 40% to 57%, but mainly towards the lower end of this range.
Regardless of the issues of seeding, etc. all these problems could have been solved by running the second session as an interleaved Howell movement, that's to say a Howell where the "phantom" pairs are actually flesh-and-blood creatures that sat in the other direction for the first session. Thus, every pair would play every other pair in the event. It works perfectly for a 10-table event (or for 4, 7 or 14 tables). Admittedly, the first session would have to be 10 rounds long - and in practice one round (and therefore one opponent from a different strat) would have to be missed, but that would be only 5% missed. As it was, we played 13 different pairs, thus not directly meeting 35% of the pairs).
But this seems to me to be the fairest, and most enjoyable way of running a 10-table two-session event. Is it the ACBL that discriminates so? Or District 25? Or is it just that the directors are too busy to print out the movement slips? I don't know.
While I'm on the subject of directors, I find it annoying that they don't take note of who the slow players are. It would be especially good if they were proactive and requested the slow players to speed up when it was appropriate. As it is, when a table gets behind both pairs suffer equally from "speed up" cautions and the possible loss of a board. This is especially annoying if the pair in question is a less experienced pair that might easily have given a good result on the unplayed board.
* Let me note in passing here the very sad news of Jim Greer's recent death. Jim was also born in Glasgow and was one of the nicest, kindest, funniest bridge players I've known. He was also a terrific player with a special reputation for matchpoints. We were looking forward to seeing Jim and Maeve at the NABC in Seattle and perhaps even teaming up with them if schedules allowed. He will be very much missed.
Showing posts with label howell. Show all posts
Showing posts with label howell. Show all posts
Saturday, November 19, 2011
Thursday, March 11, 2010
Howell some more
You've been asking for it. Having explained the logic behind the 4-table Howell movement in a previous post, what about the other Howell movements? Well, here's the three table movement. Actually, this is much more complex than the four table movement. Edwin would have had to be taking opium or something for this dream to materialize.
As always, there's an odd number of (total) tables (because after counting the stationary pair, we have 2n – 1 "teams" of a real pair and a phantom pair – where n is the number of tables). In this case, n is 3 so we need five total tables. E/W pairs still move down 2 tables and N/S pairs 3 tables. The difference from the four-board movement is in the boards. The board sets still move down a table each round. But in the three-table Howell, there are only four board sets to begin with (if you recall, in the last round all three tables relay the remaining board set).
So the new rules applying to the boards are as follows: the two (logical) tables on either side of "Table 1" (the table at which the stationary pair resides) viz. tables 2 and 5, are twinned; and the remaining two tables, viz. tables 3 and 4, are also twinned. When a pair arrives at one of these twinned tables, they look to see which boards are in place. If there are none (table 5 starts with no boards – the 5th set doesn't appear until the final round) or if they have already played the boards, they "borrow" the boards from the twin table.
Otherwise, it works pretty much exactly the same was as does the four-table Howell movement. Let's see how things work out for the three table movement that corresponds to this movement on the Bridge Guys site:
Other movements (more than four tables) are actually simpler even than the four-table Howell. In these other movements, the bye-stand tables (the tables that the phantom pairs "play" at) are at consecutive tables. It is logical therefore that the tables on either side of the bye-stand should be numbered 1 and n. Note that the position of "table 1" in the three and four-table Howell movements is completely arbitrary.
In practice, as the number of rounds for a full Howell must be 2n – 1 (everyone plays everyone else), some Howells could become rather lengthy affairs. n=7 for instance, gives us the practical limit: 13 rounds of 2 boards. Beyond that come the "three-quarter" Howells where the number of rounds is curtailed.
A seven-table Howell fits very nicely as the final session of a "complete" movement wherein 26 pairs meet in a regular 13-round Mitchell followed by two-interlaced 7-table Howells. In this latter session, each "team" is made up of one pair from the N-S pairs from the first session and one pair from the E-W pairs from the first session. The teams are of course not real (their scores are not summed) and are only teams in the sense of Howell's dream. But in this movement, both pairs actually play bridge (unlike in non-interlaced Howells) so there are no bye-stands – all tables are in actual use.
You can also run this elegant two-session movement with 20 pairs, 14 pairs and 8 pairs, although in practice the latter is not done.
As always, there's an odd number of (total) tables (because after counting the stationary pair, we have 2n – 1 "teams" of a real pair and a phantom pair – where n is the number of tables). In this case, n is 3 so we need five total tables. E/W pairs still move down 2 tables and N/S pairs 3 tables. The difference from the four-board movement is in the boards. The board sets still move down a table each round. But in the three-table Howell, there are only four board sets to begin with (if you recall, in the last round all three tables relay the remaining board set).
So the new rules applying to the boards are as follows: the two (logical) tables on either side of "Table 1" (the table at which the stationary pair resides) viz. tables 2 and 5, are twinned; and the remaining two tables, viz. tables 3 and 4, are also twinned. When a pair arrives at one of these twinned tables, they look to see which boards are in place. If there are none (table 5 starts with no boards – the 5th set doesn't appear until the final round) or if they have already played the boards, they "borrow" the boards from the twin table.
Otherwise, it works pretty much exactly the same was as does the four-table Howell movement. Let's see how things work out for the three table movement that corresponds to this movement on the Bridge Guys site:
| logical # | actual # | Rnd 1: board set | Rnd 1: NS pair | Rnd 1: EW pair | Rnd 2: board set | Rnd 2: NS pair | Rnd 2: EW pair |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 6 (1) | 1 | 2 | 6 (2) | 2 |
| 2 | twinned with 5 | 2 | 3 | 4 | 3 | 4 | 5 |
| 3 | twinned with 4 | 3 | 5 | 2 | 4 | 1 | 3 |
| 4 | 3 | 4 | 2 | 5 | none (4) | 3 | 1 |
| 5 | 2 | none (2) | 4 | 3 | 1 | 5 | 4 |
Other movements (more than four tables) are actually simpler even than the four-table Howell. In these other movements, the bye-stand tables (the tables that the phantom pairs "play" at) are at consecutive tables. It is logical therefore that the tables on either side of the bye-stand should be numbered 1 and n. Note that the position of "table 1" in the three and four-table Howell movements is completely arbitrary.
In practice, as the number of rounds for a full Howell must be 2n – 1 (everyone plays everyone else), some Howells could become rather lengthy affairs. n=7 for instance, gives us the practical limit: 13 rounds of 2 boards. Beyond that come the "three-quarter" Howells where the number of rounds is curtailed.
A seven-table Howell fits very nicely as the final session of a "complete" movement wherein 26 pairs meet in a regular 13-round Mitchell followed by two-interlaced 7-table Howells. In this latter session, each "team" is made up of one pair from the N-S pairs from the first session and one pair from the E-W pairs from the first session. The teams are of course not real (their scores are not summed) and are only teams in the sense of Howell's dream. But in this movement, both pairs actually play bridge (unlike in non-interlaced Howells) so there are no bye-stands – all tables are in actual use.
You can also run this elegant two-session movement with 20 pairs, 14 pairs and 8 pairs, although in practice the latter is not done.
Monday, March 8, 2010
Howell Movement
Born on Nantucket 150 years ago this year, Edwin Cull Howell (died Richmond, VA 1907) was one smart dude. Even though he died 18 years before our great game of Contract Bridge was invented, he devised one of the most commonly used movements for playing, er, Whist. And in this his sesquicentennial year, I've finally figured out how his movement works. I've searched in vain for an explanation of the movement. All I've ever seen are charts which detail what actually happens. I've never seen it actually explained. I'd been on the right track for quite a while, but there were a couple of crucial details that eluded me.
Let's approach it in a somewhat round-about way. The owner of a small club has a rather strange dream. He has exactly seven tables and decides to invite seven teams to come and play a match-pointed team game. It'll be a little bit like a board-a-match, but where each team's final score is the sum of all the match-points earned by the N/S pair added to those earned by the E/W pair. Another rule is that for every new round, each team's captain can decide which way to field its two pairs. There's just one snag. In each round, the two pairs of any one team will actually meet each other so the team can play the boards out if they like, but of course those scores won't make any difference to the result (they will balance out).
The plan is that at the end of each round, the boards will go down one table, the E/W pairs will go down two tables and the N/S pairs will go down three tables.
At the last minute, a pair of gate-crashers hobbles in – one on crutches, the other in a wheelchair. After a little thought, the director realizes that this is going to work out just fine. This pair will "bump" the N/S pair whenever an entire team is due to meet. As it happens, these meetings are always at the same table so this stationary pair will never have to move. This pair is assigned the number 8.
But the weird nature of the dream is only just beginning. As the game is finally about to start, the director notices that three of the tables seem to have had their chairs stolen and can't be used (so pairs arriving at these tables will be sitting – or standing – out the round). The team captains are quick to ensure that their best pairs (naturally, these are the pairs including themselves) are sitting at real tables. As the game gets started and all goes quiet, music from next door drifts in: Empty chairs at empty tables. Hearing this, one of the smarter players of the idle pairs realizes that as the movement progresses, whenever the pair makes it to a real table, the better half will be arriving at a chair-less table. The captain will no doubt switch them around so that the idle pair remains idle. In fact, this pair realizes that they are going to spend the entire evening standing around never getting to play a single card! They decide to go home. The other idlers follow them.
The remaining players finish the evening after seven rounds and the scores are totaled. Each of the original teams (1-7), gets the score achieved by their "good" pair, while the late (stationary) pair that so fortuitously arrived gets the score for pair 8. An enjoyable game of bridge between eight pairs with a single winner, and every pair playing every other pair, has just been completed. As it happens, the "weaker" pairs of each of the seven original teams never got to play a hand: they didn't really need to know how to play bridge (or whist). In fact, they don't need to exist at all – they're phantoms!
Perhaps Edwin Howell had a dream like this. Or maybe he came at the movement another way. But it was definitely a brilliant idea.
So let's now see how the tables are arranged and how it all works in real life. Logical table number corresponds to the table numbers in the dream. Physical table number is the number of the (real) table in a Howell movement. This example corresponds to the chart shown on the Bridge Guys web site. The table shows how everything is arranged for rounds one and two. Bumped pairs are shown in parentheses. Phantom pairs are marked in red italics.
(see also Howell some more)
Let's approach it in a somewhat round-about way. The owner of a small club has a rather strange dream. He has exactly seven tables and decides to invite seven teams to come and play a match-pointed team game. It'll be a little bit like a board-a-match, but where each team's final score is the sum of all the match-points earned by the N/S pair added to those earned by the E/W pair. Another rule is that for every new round, each team's captain can decide which way to field its two pairs. There's just one snag. In each round, the two pairs of any one team will actually meet each other so the team can play the boards out if they like, but of course those scores won't make any difference to the result (they will balance out).
The plan is that at the end of each round, the boards will go down one table, the E/W pairs will go down two tables and the N/S pairs will go down three tables.
At the last minute, a pair of gate-crashers hobbles in – one on crutches, the other in a wheelchair. After a little thought, the director realizes that this is going to work out just fine. This pair will "bump" the N/S pair whenever an entire team is due to meet. As it happens, these meetings are always at the same table so this stationary pair will never have to move. This pair is assigned the number 8.
But the weird nature of the dream is only just beginning. As the game is finally about to start, the director notices that three of the tables seem to have had their chairs stolen and can't be used (so pairs arriving at these tables will be sitting – or standing – out the round). The team captains are quick to ensure that their best pairs (naturally, these are the pairs including themselves) are sitting at real tables. As the game gets started and all goes quiet, music from next door drifts in: Empty chairs at empty tables. Hearing this, one of the smarter players of the idle pairs realizes that as the movement progresses, whenever the pair makes it to a real table, the better half will be arriving at a chair-less table. The captain will no doubt switch them around so that the idle pair remains idle. In fact, this pair realizes that they are going to spend the entire evening standing around never getting to play a single card! They decide to go home. The other idlers follow them.
The remaining players finish the evening after seven rounds and the scores are totaled. Each of the original teams (1-7), gets the score achieved by their "good" pair, while the late (stationary) pair that so fortuitously arrived gets the score for pair 8. An enjoyable game of bridge between eight pairs with a single winner, and every pair playing every other pair, has just been completed. As it happens, the "weaker" pairs of each of the seven original teams never got to play a hand: they didn't really need to know how to play bridge (or whist). In fact, they don't need to exist at all – they're phantoms!
Perhaps Edwin Howell had a dream like this. Or maybe he came at the movement another way. But it was definitely a brilliant idea.
So let's now see how the tables are arranged and how it all works in real life. Logical table number corresponds to the table numbers in the dream. Physical table number is the number of the (real) table in a Howell movement. This example corresponds to the chart shown on the Bridge Guys web site. The table shows how everything is arranged for rounds one and two. Bumped pairs are shown in parentheses. Phantom pairs are marked in red italics.
| logical # | physical (play) # | Rnd 1: board set | Rnd 1: NS pair | Rnd 1: EW pair | Rnd 2: board set | Rnd 2: NS pair | Rnd 2: EW pair |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 8 (1) | 1 | 2 | 8 (2) | 2 |
| 2 | 2 | 2 | 6 | 5 | 3 | 7 | 6 |
| 3 | 3 | 3 | 4 | 2 | 4 | 5 | 3 |
| 4 | bye stand | 4 | 2 | 6 | 5 | 3 | 7 |
| 5 | 4 | 5 | 7 | 3 | 6 | 1 | 4 |
| 6 | bye stand | 6 | 5 | 7 | 7 | 6 | 1 |
| 7 | bye stand | 7 | 3 | 4 | 1 | 4 | 5 |
(see also Howell some more)
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