Help
I run a lot of small tourneys (6 5 4 or 3 tables) and am not sure how the swiss movement works and whether it would not be my best option.
Can someone give me a quick summary pleaase? I would obviously like to run it in such a way that the most pairs play vs. one another. I once clicked "swiss" with 4 pairs tables and it seemed to work best but it was honestly just an experiment and I didnt' learn anything from it.
So, assuming 6 tables, what would the # of rounds be, etc. (assume 12 boards for now) and how would it work? Any help is much apprecited.
Steve
Best Movement?
#2
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Posted 2004-February-11, 02:57
I appeciate all the time & effort the Directors volunteer to make competitive bridge enjoyable to others. I like the short tourney versions, especially 8, 10 or 12 board versions.
However when the tourney gets really short, the shortest I have seen is 4, I request the Director to make this an MP game and not IMP.
Everyone knows the element of luck increases as the duration of the tournament decreases, and in IMP one result is enough to swing you to the 1st spot. These 4 board IMP tourneys are pure lottery in my opinion.
However when the tourney gets really short, the shortest I have seen is 4, I request the Director to make this an MP game and not IMP.
Everyone knows the element of luck increases as the duration of the tournament decreases, and in IMP one result is enough to swing you to the 1st spot. These 4 board IMP tourneys are pure lottery in my opinion.
♥ Bridge Players do it with Finesse ♥
#3
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Posted 2004-February-11, 08:14
None of the momevents guarantee that all the pairs will face each other.
Since you want 12 boards, and expect 3 tables, you should probably use
Clocked: 4 boards per round, 3 rounds
No point doing anything else, since the 3 NS will play the 3 EW and that is that.
You can make it 2 boards per round, 6 rounds, but that will just mean each EW pair will sweep thru the NS field once, then do it again. Not clear there is any gain.
Unclocked: 2 boards per round, 6 rounds for unclocked movements
Here, tables are matched up as they complete the previous round. So
while playbacks are possible, EW and NS are not constant so you will
probably see more combinations. If all pairs play at the same speed, 1x12 might work better (more rounds = more possible opps)
Swiss: Like unclocked. Since the order depends on score (each round, the pairs are scored. Then sorted by score. Then, 1 plays 2 at table 1, 2 plays 3 at table2 , 3 plays 4 at table 3. This movement does not mind issuing repeated playbacks.
If all pairs play at the same speed 1x12 *might** work beter (more rounds = more possible opps - i think. Does a swiss tend to clump the scores together or sread them out? Don't know.)
Survivor: You should not use Survivor for small games like this.
Since you want 12 boards, and expect 3 tables, you should probably use
Clocked: 4 boards per round, 3 rounds
No point doing anything else, since the 3 NS will play the 3 EW and that is that.
You can make it 2 boards per round, 6 rounds, but that will just mean each EW pair will sweep thru the NS field once, then do it again. Not clear there is any gain.
Unclocked: 2 boards per round, 6 rounds for unclocked movements
Here, tables are matched up as they complete the previous round. So
while playbacks are possible, EW and NS are not constant so you will
probably see more combinations. If all pairs play at the same speed, 1x12 might work better (more rounds = more possible opps)
Swiss: Like unclocked. Since the order depends on score (each round, the pairs are scored. Then sorted by score. Then, 1 plays 2 at table 1, 2 plays 3 at table2 , 3 plays 4 at table 3. This movement does not mind issuing repeated playbacks.
If all pairs play at the same speed 1x12 *might** work beter (more rounds = more possible opps - i think. Does a swiss tend to clump the scores together or sread them out? Don't know.)
Survivor: You should not use Survivor for small games like this.
#4
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Posted 2004-February-11, 08:30
I am not particularly fond of "survivor" events when a director is available. This has nothing to do with my being booted from an event... heck if I am so far out that I get clipped out, I would WANT TO GET zapped. But, rather, I thnk the fairest competition is when everyone gets a shot at playing against everyone esle. Of course, this isn't usually possible, but I think this is best.
This is why my favorite movement is a howell or at least a scrambled howell. The swiss events sort of approach this (kinda) as the directions people sit get scrambled. But in a 3 or 4 table movement, I would love to see a pure howell where everyone plays everyone else. And yes, I know this movement is not implimented on BBO... but such dreams some day may come true...
The problem with 1x12 events is you have 12 opportunities to sit and wait for the next round. I would much prefer 4X3 (only 3 wait periods) or 3x4 (with four wait periods). As much as I hate "playbacks" uncocked movements are nice as the delays are usually not long at all (unless you get stuck in the slow group movement dark hole, where the clock marches onward to minus 6 and minus 8 minutes each round and you sit waiting for the last slow table to finish)....
Ben
This is why my favorite movement is a howell or at least a scrambled howell. The swiss events sort of approach this (kinda) as the directions people sit get scrambled. But in a 3 or 4 table movement, I would love to see a pure howell where everyone plays everyone else. And yes, I know this movement is not implimented on BBO... but such dreams some day may come true...
The problem with 1x12 events is you have 12 opportunities to sit and wait for the next round. I would much prefer 4X3 (only 3 wait periods) or 3x4 (with four wait periods). As much as I hate "playbacks" uncocked movements are nice as the delays are usually not long at all (unless you get stuck in the slow group movement dark hole, where the clock marches onward to minus 6 and minus 8 minutes each round and you sit waiting for the last slow table to finish)....
Ben
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#5
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Posted 2004-February-11, 08:41
If someone has an alorithm for implementing Howell movements, I'll look at implementing it.
What I need is logic that, either
1) given numtables, num rounds, tells me what the assignments should be for each round. Numtables will be anything from 2-40 or so
2) given numtables, numrounds, current round number, an EW pair and a NS Pair, tells me where they should go for the next round
About the unclocked: a few weeks ago we implemented code to alleviate the "slow group" problem ( for instance, we don't allow a new board to start in a round that is already slow) and the excessive playback problem. But this won't help if a table is slow to finish a board already in play.
What I need is logic that, either
1) given numtables, num rounds, tells me what the assignments should be for each round. Numtables will be anything from 2-40 or so
2) given numtables, numrounds, current round number, an EW pair and a NS Pair, tells me where they should go for the next round
About the unclocked: a few weeks ago we implemented code to alleviate the "slow group" problem ( for instance, we don't allow a new board to start in a round that is already slow) and the excessive playback problem. But this won't help if a table is slow to finish a board already in play.
#6
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Posted 2004-February-11, 09:35
I am no expert on howell movements, and there maybe better ways than the sequence I propose for 3, 4, 5 and 6 tables below. Get much more than that, and of course no way to play that many boards on line (well, 1 board per round, but as I said in earlier post, I am not fond of 1x12 or 1x8 things). I
I think I got the following movement flow right, but maybe someone like richard who is mathematically inclined can help double check I am not sending everyone to the same table each round...
Here is the logic for a 3 table howell movement where all six pairs play against each other once. Starting with the "flow" logic, and then showing who is sitting at which table each round.
In a three table howell NS table 1 stays stationary
EW table 1 go to table 2 E/W
Table 2 N/S got to table 1 E/W
Table 2 E/W got to table 3 E/W
Table 3 N/S got to table 2 N/S
Table 3 E/W go to table 3 N/S
This give us the following five rounds...
TABLE NS EW = RD#1
1 6 1
2 2 5
3 3 4
TABLE NS EW = RD #2
1 6 2
2 3 1
3 4 5
TABLE NS EW = RD #3
1 6 3
2 4 2
3 5 1
TABLE NS EW = RD #4
1 6 4
2 5 3
3 1 2
TABLE NS EW = RD #5
1 6 5
2 1 4
3 2 3
Clearly, I think this is the fairest movement.
Next, logic for a 4 table howell... just the flow of the players after each round this time....
Table 1 N/S stationary entire time
E/W got to 3 E/W
Table 2. N/S move to 3 N/S
E/W move to 4 N/S
Table 3. N/S move to 1 E/W
E/W move to 2 E/W
Table 4. N/S move to 4 E/W
E/W move to 2 N/S
Next logic for 5 table howell
Table 1 N/S stationary entire time
E/W got to 2 N/S
Table 2. N/S move to 2 E/W
E/W move to 3 E/W
Table 3. N/S move to 4 E/W
E/W move to 5N/S
Table 4. N/S move to 5 E/W
E/W move to 1 E/W
Table 5. N/S move to table 4 N/S
E/W move to tavle 3 N/S
Next logic for 6 table howell
Table 1 N/S stationary entire time
E/W got to 2 N/S
Table 2. N/S move to 5 E/W
E/W move to 3 E/W
Table 3. N/S move to 5 N/S
E/W move to 6 E/W
Table 4. N/S move to 4 E/W
E/W move to 1 E/W
Table 5. N/S move to table 6 N/S
E/W move to tavle 3 N/S
Table 6. N/S move to 2 E/W
E/W moves to 4 N/S
I think I got the following movement flow right, but maybe someone like richard who is mathematically inclined can help double check I am not sending everyone to the same table each round...
Here is the logic for a 3 table howell movement where all six pairs play against each other once. Starting with the "flow" logic, and then showing who is sitting at which table each round.
In a three table howell NS table 1 stays stationary
EW table 1 go to table 2 E/W
Table 2 N/S got to table 1 E/W
Table 2 E/W got to table 3 E/W
Table 3 N/S got to table 2 N/S
Table 3 E/W go to table 3 N/S
This give us the following five rounds...
TABLE NS EW = RD#1
1 6 1
2 2 5
3 3 4
TABLE NS EW = RD #2
1 6 2
2 3 1
3 4 5
TABLE NS EW = RD #3
1 6 3
2 4 2
3 5 1
TABLE NS EW = RD #4
1 6 4
2 5 3
3 1 2
TABLE NS EW = RD #5
1 6 5
2 1 4
3 2 3
Clearly, I think this is the fairest movement.
Next, logic for a 4 table howell... just the flow of the players after each round this time....
Table 1 N/S stationary entire time
E/W got to 3 E/W
Table 2. N/S move to 3 N/S
E/W move to 4 N/S
Table 3. N/S move to 1 E/W
E/W move to 2 E/W
Table 4. N/S move to 4 E/W
E/W move to 2 N/S
Next logic for 5 table howell
Table 1 N/S stationary entire time
E/W got to 2 N/S
Table 2. N/S move to 2 E/W
E/W move to 3 E/W
Table 3. N/S move to 4 E/W
E/W move to 5N/S
Table 4. N/S move to 5 E/W
E/W move to 1 E/W
Table 5. N/S move to table 4 N/S
E/W move to tavle 3 N/S
Next logic for 6 table howell
Table 1 N/S stationary entire time
E/W got to 2 N/S
Table 2. N/S move to 5 E/W
E/W move to 3 E/W
Table 3. N/S move to 5 N/S
E/W move to 6 E/W
Table 4. N/S move to 4 E/W
E/W move to 1 E/W
Table 5. N/S move to table 6 N/S
E/W move to tavle 3 N/S
Table 6. N/S move to 2 E/W
E/W moves to 4 N/S
--Ben--
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Posted 2004-February-12, 10:22
Hi Ben,
I suggested this type of movement here short after the tourneys started last year. I is not really Howell, though. In face to face bridge it is used for barometer tourneys where you have each board duplicated so that it can be played at all tables simultaneously.
As in online bridge a board is always played simultaneously at all tables, the movement could be used for any clocked tournament. I would really recommend to replace the existing clocked movement by this one, as it is nicer for small tourneys and has the additional benefit that the pairs do not all stay on NS or EW like today.
The only disadvantage this movement would have had in the past, that it would have been more difficult for the director to locate movies of previous hands, is gone with the latest beta.
Karl
I suggested this type of movement here short after the tourneys started last year. I is not really Howell, though. In face to face bridge it is used for barometer tourneys where you have each board duplicated so that it can be played at all tables simultaneously.
As in online bridge a board is always played simultaneously at all tables, the movement could be used for any clocked tournament. I would really recommend to replace the existing clocked movement by this one, as it is nicer for small tourneys and has the additional benefit that the pairs do not all stay on NS or EW like today.
The only disadvantage this movement would have had in the past, that it would have been more difficult for the director to locate movies of previous hands, is gone with the latest beta.
Karl
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Posted 2004-February-15, 07:00
I support Ben and Karl very strongly! In addition I'll send to uday all Howell movements I have. It's not a hard work to implement it I think.
Dusan
Dusan
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Posted 2004-February-16, 06:03
Oh boy! Thanks in advance Uday if we can have Howells!
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Posted 2004-February-16, 07:22
Howell type movements, like all other movements in face to face bridge (except those for barometer tourneys), take care that not only you play against different opps in each round, but also that you play a set of boards that is not used by another table. But that is not what you want in online Bridge Brige, as there each board is played at all tables simultaneously. thereby preventing that you hear information about a board you will play later in the tourney in advance. So the movement in online bridge can be much simpler, like the one Ben presented in this thread. I consider it ideal for clocked tourneys.
Karl
Karl
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Posted 2004-February-16, 08:28
All you wrote is right, Karl, I agree. Nevertheless Howell can't damage anything and is much better balanced. There are couple of pairs In Bens movement which play only 2 times on different lines, e.g. Always better then Mitchell, I don't like Mitchell in small tournaments with one final ranking.
Dusan
Dusan
#12
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Posted 2004-February-16, 09:41
Quote
There are couple of pairs In Bens movement which play only 2 times on different lines,
If I somehow messed up the howell movement, I apologize. But I still like the concept of a howell for small groups, and scrambled howells for one person winners (rather than winner EW and winner NS). Surely someone knows how to put together howell movements.
A couple of people point out that howells control movement of boards and people, so that each table plays different hands. This is true, this is also true of the mitchell movement we are currently using in the tournments. But somehow they don't mention the same point, that all tables play the same boards on line at the same time... this is obviously a function of "duplciate boards" used in F2F where you would need the same number of sets of boards as rounds if you were going to play all the same hands at all the tables during a single round. Computers easily overcome this limitation.
Ben
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#13
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Posted 2004-February-16, 14:04
Here is an simple algorithm for producing Howells for online pairs games:
(1) Number the pairs from 1 to (number of pairs). If there is an odd number, add a "sitout" pair at the end.
(2) In round one, the matchups are:
Highest numbered pair versus lowest numbered pair
2nd highest numbered pair vs 2nd lowest number pair
3rd highest numbered pair vs 3rd lowest numbered pair
...and so on. The sum of each first round matchup adds to (pairs + 1)
3) In round two, and all later rounds:
the highest numbered pair stays where they are
every other pair follows (takes the most recent spot of) the pair with the next lowest number, with the one exception that pair one follows the second highest numbered pair
Example: 7 table Howell (14 pairs)
Round 01: 14.vs.01 - 13 vs 02 - 12.vs.03 - 11 vs 04 - 10.vs.05 - 09 vs 06 - 08.vs.07
Round 02: 14 vs 02 - 01.vs.03 - 13 vs 04 - 12.vs.05 - 11 vs 06 - 10.vs.07 - 09 vs 08
Round 03: 14.vs.03 - 02 vs 04 - 01.vs.05 - 13 vs 06 - 12.vs.07 - 11 vs 08 - 10.vs.09
Round 04: 14 vs 04 - 03.vs.05 - 02 vs 06 - 01.vs.07 - 13 vs 08 - 12.vs.09 - 11 vs 10
Round 05: 14.vs.05 - 04 vs 06 - 03.vs.07 - 02 vs 08 - 01.vs.09 - 13 vs 10 - 12.vs.11
Round 06: 14 vs 06 - 05.vs.07 - 04 vs 08 - 03.vs.09 - 02 vs 10 - 01.vs.11 - 13 vs 12
Round 07: 14.vs.07 - 06 vs 08 - 05.vs.09 - 04 vs 10 - 03.vs.11 - 02 vs 12 - 01.vs.13
Round 08: 14 vs 08 - 07.vs.09 - 06 vs 10 - 05.vs.11 - 04 vs 12 - 03.vs.13 - 02 vs 01
Round 09: 14.vs.09 - 08 vs 10 - 07.vs.11 - 06 vs 12 - 05.vs.13 - 04 vs 01 - 03.vs.02
Round 10: 14 vs 10 - 09.vs.11 - 08 vs 12 - 07.vs.13 - 06 vs 01 - 05.vs.02 - 04 vs 03
Round 11: 14.vs.11 - 10 vs 12 - 09.vs.13 - 08 vs 01 - 07.vs.02 - 06 vs 03 - 05.vs.04
Round 12: 14 vs 12 - 11.vs.13 - 10 vs 01 - 09.vs.02 - 08 vs 03 - 07.vs.04 - 06 vs 05
Round 13: 14.vs.13 - 12 vs 01 - 11.vs.02 - 10 vs 03 - 09.vs.04 - 08 vs 05 - 07.vs.06
The other thing you might do would be to flip pair 14 from N-S to E-W, but otherwise this works for any even number of pairs (and for odd numbers you simply make the high pair the stationary pair.)
Posleda has pointed out that this means that some pairs play the same boards in the same direction often: for example, Pair 01 and 02 play only two of the thirteen rounds (rounds 02 and 08) in different seats. I'm not 100% sure, but I think the way around this might be to switch positions in a checkerboard pattern, where in odd numbered rounds the 1st 3rd 5th 7th matchups are flipped, and in even numbered rounds the 2nd 4th 6th 8th etc. are flipped. I added dots to the flipped matchups above. It may not be a perfect solution, but if it is a fairly good one and we can do Howells of all sizes with one simple algorithm, that is probably just what Uday wants.
(1) Number the pairs from 1 to (number of pairs). If there is an odd number, add a "sitout" pair at the end.
(2) In round one, the matchups are:
Highest numbered pair versus lowest numbered pair
2nd highest numbered pair vs 2nd lowest number pair
3rd highest numbered pair vs 3rd lowest numbered pair
...and so on. The sum of each first round matchup adds to (pairs + 1)
3) In round two, and all later rounds:
the highest numbered pair stays where they are
every other pair follows (takes the most recent spot of) the pair with the next lowest number, with the one exception that pair one follows the second highest numbered pair
Example: 7 table Howell (14 pairs)
Round 01: 14.vs.01 - 13 vs 02 - 12.vs.03 - 11 vs 04 - 10.vs.05 - 09 vs 06 - 08.vs.07
Round 02: 14 vs 02 - 01.vs.03 - 13 vs 04 - 12.vs.05 - 11 vs 06 - 10.vs.07 - 09 vs 08
Round 03: 14.vs.03 - 02 vs 04 - 01.vs.05 - 13 vs 06 - 12.vs.07 - 11 vs 08 - 10.vs.09
Round 04: 14 vs 04 - 03.vs.05 - 02 vs 06 - 01.vs.07 - 13 vs 08 - 12.vs.09 - 11 vs 10
Round 05: 14.vs.05 - 04 vs 06 - 03.vs.07 - 02 vs 08 - 01.vs.09 - 13 vs 10 - 12.vs.11
Round 06: 14 vs 06 - 05.vs.07 - 04 vs 08 - 03.vs.09 - 02 vs 10 - 01.vs.11 - 13 vs 12
Round 07: 14.vs.07 - 06 vs 08 - 05.vs.09 - 04 vs 10 - 03.vs.11 - 02 vs 12 - 01.vs.13
Round 08: 14 vs 08 - 07.vs.09 - 06 vs 10 - 05.vs.11 - 04 vs 12 - 03.vs.13 - 02 vs 01
Round 09: 14.vs.09 - 08 vs 10 - 07.vs.11 - 06 vs 12 - 05.vs.13 - 04 vs 01 - 03.vs.02
Round 10: 14 vs 10 - 09.vs.11 - 08 vs 12 - 07.vs.13 - 06 vs 01 - 05.vs.02 - 04 vs 03
Round 11: 14.vs.11 - 10 vs 12 - 09.vs.13 - 08 vs 01 - 07.vs.02 - 06 vs 03 - 05.vs.04
Round 12: 14 vs 12 - 11.vs.13 - 10 vs 01 - 09.vs.02 - 08 vs 03 - 07.vs.04 - 06 vs 05
Round 13: 14.vs.13 - 12 vs 01 - 11.vs.02 - 10 vs 03 - 09.vs.04 - 08 vs 05 - 07.vs.06
The other thing you might do would be to flip pair 14 from N-S to E-W, but otherwise this works for any even number of pairs (and for odd numbers you simply make the high pair the stationary pair.)
Posleda has pointed out that this means that some pairs play the same boards in the same direction often: for example, Pair 01 and 02 play only two of the thirteen rounds (rounds 02 and 08) in different seats. I'm not 100% sure, but I think the way around this might be to switch positions in a checkerboard pattern, where in odd numbered rounds the 1st 3rd 5th 7th matchups are flipped, and in even numbered rounds the 2nd 4th 6th 8th etc. are flipped. I added dots to the flipped matchups above. It may not be a perfect solution, but if it is a fairly good one and we can do Howells of all sizes with one simple algorithm, that is probably just what Uday wants.
ACBL TD--got my start in 2002 directing games at BBO!
Please come back to the live game; I directed enough online during COVID for several lifetimes.
Bruce McIntyre,Yamaha WX5 Roland AE-10G AKAI EWI SOLO virtuoso-in-training
Please come back to the live game; I directed enough online during COVID for several lifetimes.
Bruce McIntyre,
#14
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Posted 2004-February-16, 14:22
TY. I will look into replacing the standard clocked movement with this one.
Is there a similar simple movement for individuals?
Is there a similar simple movement for individuals?
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Posted 2004-February-16, 15:38
McBruce, on Feb 17 2004, 05:04 AM, said:
Here is an simple algorithm for producing Howells for online pairs games:
This is Bens movement in other words. For me it isn't Howell, only Howell-like movement by reason of unbalance (my previous reply). E.g. pairs 1 a 2 play once together, once on different lines and 11 times play the same hand. This is very near to Mitchell, from Howell is only the principle of moving pairs. But still better then Mitchell.
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Posted 2004-February-16, 15:39
(Long post deleted on alternate algorithm, found equivalent to McBruce's, only different arranging. [taking from chess, where alternating colors (directions) is important.] His math is simpler.)
Taking a look at McBruce's example, where N is the number of rounds, R the round and T the table:
NS[R,T] = N+R-T+1 mod N if T => 2
NS[R,T] = N+1 if T=1
EW[R,T] = R+T-1 mod N
(maybe) flip NS and EW if R even
[use N instead of 0 in this context, i.e. add N when result is 0]
But, this does not scale, and is highly dependent of the number of rounds.
You need to have sections of number of rounds (+1 to make if even if necessary) pairs (half it for number of tables).
Posleda: take a closer look. I think in McBruce's example, all (but 14, which you can flip to get that), play 7 rounds in one direction, and 6 in another, being the direction facing 14 the difference.
Taking a look at McBruce's example, where N is the number of rounds, R the round and T the table:
NS[R,T] = N+R-T+1 mod N if T => 2
NS[R,T] = N+1 if T=1
EW[R,T] = R+T-1 mod N
(maybe) flip NS and EW if R even
[use N instead of 0 in this context, i.e. add N when result is 0]
But, this does not scale, and is highly dependent of the number of rounds.
You need to have sections of number of rounds (+1 to make if even if necessary) pairs (half it for number of tables).
Posleda: take a closer look. I think in McBruce's example, all (but 14, which you can flip to get that), play 7 rounds in one direction, and 6 in another, being the direction facing 14 the difference.
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Posted 2004-February-16, 15:40
uday, on Feb 17 2004, 05:22 AM, said:
Is there a similar simple movement for individuals?
Yes, Rainbow. I'll send it to you with Howells.
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Posted 2004-February-16, 16:39
Very nice description of Rainbow in The Rainbow Movement for Individual Duplicate Games
There is a caveat: sections have to have a prime number of tables. (This is needed to guarantee you'll never meet a player twice, as partner or opp)
Inside a section (in a given round), R round, T table, N size of section:
N[R,T] = T
W[R,T] = (T+(R-1)*2) mod N + N
S[R,T] = (T+(R+1)) mod N + N*2
E[R,T] = (T+(R+1)*2) mod N + N*3
Individuals could not be 1 board per round, because then you would never have a change of direction for the players.
If 2 boards/round, flip South and East.
If 3 boards/round, East goes West then South, West goes South then East, South goes East then West.
Nice movement!
There is a caveat: sections have to have a prime number of tables. (This is needed to guarantee you'll never meet a player twice, as partner or opp)
Inside a section (in a given round), R round, T table, N size of section:
N[R,T] = T
W[R,T] = (T+(R-1)*2) mod N + N
S[R,T] = (T+(R+1)) mod N + N*2
E[R,T] = (T+(R+1)*2) mod N + N*3
Individuals could not be 1 board per round, because then you would never have a change of direction for the players.
If 2 boards/round, flip South and East.
If 3 boards/round, East goes West then South, West goes South then East, South goes East then West.
Nice movement!
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Posted 2004-February-16, 17:01
For individuals, a OAFA (one algorithm fits all) might be:
1) Count the players from 1, adding phantoms to get the total divisible by 4.
2) Seat the players for round one as follows:
highest at table 1 South
lowest at table 1 North
2nd highest at table 2 South
2nd lowest at table 2 North
3rd highest at table 3 South
etc. until you run out of North-South seats, then
next highest player at highest numbered table East
next lowest player at lowest numbered table West
...and so on. Note that the East-West pairs are placed in the reverse order, from highest numbered table down. Adding the numbers of each first-round pair should get you (players + 1), and this adding the numbers of the four players at each table should get you 2 * (players + 1).
3) At the end of each round, the highest numbered player stays where he is, and the others take the seat of the next-lowest player (player one takes the seat of the second highest numbered player)
4) As we've discovered, it may pay to flip directions in a checkerboard pattern to reduce the frequency of two entries playing the same direction for most of the boards. If you incorporate this into the movement it is probably a good idea to do it last or the progression might be difficult to follow.
Here is the 4-table indy complete (15 rounds). The dashes indicate the checkerboard pattern where the N/S and E/W pairs should be switched.
Oh dear, follow #1 through the tournament and the poor fellow meets the same four or five people as opponents 90% of the time. Back to the drawing board...
Obviously, this won't work for unclocked movements. I think for unclocked individuals the best idea long term would be to match players by speed, institute an optional penalty to your score for finishing the boards after a certain time, and enforce a hospitality break between boards or rounds for those who are finished very early (to reduce playbacks). I am trying these wrinkles out (by directing players, not by software) in my Alphabet Tournaments and I'll keep you posted on how well it works.
1) Count the players from 1, adding phantoms to get the total divisible by 4.
2) Seat the players for round one as follows:
highest at table 1 South
lowest at table 1 North
2nd highest at table 2 South
2nd lowest at table 2 North
3rd highest at table 3 South
etc. until you run out of North-South seats, then
next highest player at highest numbered table East
next lowest player at lowest numbered table West
...and so on. Note that the East-West pairs are placed in the reverse order, from highest numbered table down. Adding the numbers of each first-round pair should get you (players + 1), and this adding the numbers of the four players at each table should get you 2 * (players + 1).
3) At the end of each round, the highest numbered player stays where he is, and the others take the seat of the next-lowest player (player one takes the seat of the second highest numbered player)
4) As we've discovered, it may pay to flip directions in a checkerboard pattern to reduce the frequency of two entries playing the same direction for most of the boards. If you incorporate this into the movement it is probably a good idea to do it last or the progression might be difficult to follow.
Here is the 4-table indy complete (15 rounds). The dashes indicate the checkerboard pattern where the N/S and E/W pairs should be switched.
1N 1S 1E 1W 2N 2S 2E 2W 3N 3S 3E 3W 4N 4S 4E 4W Round 01: 01 16--08 09 02 15 07 10 03 14--06 11 04 13 05 12 Round 02: 02 16 09 10 03 01--08 11 04 15 07 12 05 14--06 13 Round 03: 03 16--10 11 04 02 09 12 05 01--08 13 06 15 07 14 Round 04: 04 16 11 12 05 03--10 13 06 02 09 14 07 01--08 15 Round 05: 05 16--12 13 06 04 11 14 07 03--10 15 08 02 09 01 Round 06: 06 16 13 14 07 05--12 15 08 04 11 01 09 03--10 02 Round 07: 07 16--14 15 08 06 13 01 09 05--12 02 10 04 11 03 Round 08: 08 16 15 01 09 07--14 02 10 06 13 03 11 05--12 04 Round 09: 09 16--01 02 10 08 15 03 11 07--14 04 12 06 13 05 Round 10: 10 16 02 03 11 09--01 04 12 08 15 05 13 07--14 06 Round 11: 11 16--03 04 12 10 02 05 13 09--01 06 14 08 15 07 Round 12: 12 16 04 05 13 11--03 06 14 10 02 07 15 09--01 08 Round 13: 13 16--05 06 14 12 04 07 15 11--03 08 01 10 02 09 Round 14: 14 16 06 07 15 13--05 08 01 12 04 09 02 11--03 10 Round 15: 15 16--07 08 01 14 06 09 02 13--05 10 03 12 04 11
Oh dear, follow #1 through the tournament and the poor fellow meets the same four or five people as opponents 90% of the time. Back to the drawing board...
Obviously, this won't work for unclocked movements. I think for unclocked individuals the best idea long term would be to match players by speed, institute an optional penalty to your score for finishing the boards after a certain time, and enforce a hospitality break between boards or rounds for those who are finished very early (to reduce playbacks). I am trying these wrinkles out (by directing players, not by software) in my Alphabet Tournaments and I'll keep you posted on how well it works.
ACBL TD--got my start in 2002 directing games at BBO!
Please come back to the live game; I directed enough online during COVID for several lifetimes.
Bruce McIntyre,Yamaha WX5 Roland AE-10G AKAI EWI SOLO virtuoso-in-training
Please come back to the live game; I directed enough online during COVID for several lifetimes.
Bruce McIntyre,
#20
- Group: Full Members
- Posts: 66
- Joined: 2003-October-04
- Location:Czech Republic
Posted 2004-February-19, 13:16
Gerardo, on Feb 17 2004, 06:39 AM, said:
Posleda: take a closer look. I think in McBruce's example, all (but 14, which you can flip to get that), play 7 rounds in one direction, and 6 in another, being the direction facing 14 the difference.
I don't know if I don't understand you or you don't understand me or both. I try to explain more precisely.
Round 01: 1 plays EW, 2 plays EW - same
Round 02: 1 plays NS, 2 plays EW - different
Round 03: 1 plays NS, 2 plays NS - same
Round 04: 1 plays NS, 2 plays NS - same
Round 05: 1 plays NS, 2 plays NS - same
Round 06: 1 plays NS, 2 plays NS - same
Round 07: 1 plays NS, 2 plays NS - same
Round 08: 1 and 2 play together
Round 09: 1 plays EW, 2 plays EW - same
Round 10: 1 plays EW, 2 plays EW - same
Round 11: 1 plays EW, 2 plays EW - same
Round 12: 1 plays EW, 2 plays EW - same
Round 13: 1 plays EW, 2 plays EW - same
1 and 2 play 11 times in same directions (NS, EW) and only once in different (round 8 is not taken in consideration). On the other side e.g. 1 and 7 play 11 times in different directions and once in same. This means unbalanced tournament.
If you use full Howell with initial position like 5-12 13-10 2-6 4-9 14-11 7-8 1-3, you may choose any two pairs and they will play 5 to 7 times in same direction and in different too. Tournament is balanced as much as possible.
That's the difference.
Dusan