[shevek]

Given normal rate of play, a "standard" bridge session is around 3 hrs.
13 rounds x 14 minutes = 182, 9 x 20 = 180, 7 x 26 = 182.

Enough for a full morning/afternoon/evening of bridge.

Many social activities tend to be shorter: film, restaurant, theatre, football.
In the 1930s, duplicate could have evolved with 2 or 2½ hour sessions.
Why not?

I'm assuming the mathematicians made the early decisions. A pure all-play-all contest - Mitchell or Howell -
requires 13 x 2, 9 x 3, 7 x 4, etc. They aimed for a fair contest and grudgingly accepted skips & incompletes.
Timings maybe came from 6 minutes per board + 2 for the move. Hence 3 hours.

Is there any literature on this?

There is a case for shorter sessions, say 24 boards, meaning around 2 hrs 40 minutes.
This is better for retaining beginners, who sit through a series of 2 hour lesson and may be discouraged by the extra hour.
Of course supervised sessions are shortish.
On the other hand, some retirement places fill the day with sessions that play 30 boards, spanning lunch. Say 11am - 3pm.

[rhm]

You severely overestimate the influence mathematicians have on social habits.
I also think your view on the length of social activities is biased.
It it true that a standard movie today is around 90 minutes, but this is driven more by business considerations than anything else.
Remember the days when 2 movies were shown at cinemas in one performance. Theater and operas also tend to last much longer than you claim.
And if you take a full course menu in a really good restaurant, where food is prepared from fresh ingredients, you are unlikely to finish your activity in less time than a Bridge session.
Opposite to fast food there is a slow food movement here in Europe. Their typical activity certainly take longer than a typical Bridge session.
A game of tournament chess typically lasts for 4 hours.
I also do not believe that the duration should be geared to beginners when the overwhelming majority of participants tend to play the game for ages.

Rainer Herrmann

[helene_t]

It is striking so universal the 24-board sesions are. Sometimes we make it 26 or 27 but almost never more than 27 or less than 24 except when there is an additional program like a general meeting or lessons.

I think that 24 is about what almost everybody can handle, with 28 we would start runnning into issues like people getting tirred or getting too late home.

[campboy]

Well, there's also the fact that 24 is a flexible number, allowing 6-, 8- or 12-round movements. In a very large club 26 might be better as you can run a web Mitchell with 13 rounds.

[gnasher]

helene_t, on 2012-October-18, 04:21, said:

It is striking so universal the 24-board sesions are.

I once visited a club in Milan where they played 15 (I think) one-board rounds.

[gwnn]

If you square any prime number (greater than 3) and subtract 1, you get a number divisible by 24.

[Antrax]

Now that's just creepy.

[WellSpyder]

gwnn, on 2012-October-18, 04:56, said:

If you square any prime number (greater than 3) and subtract 1, you get a number divisible by 24.

Antrax, on 2012-October-18, 05:36, said:

Now that's just creepy.

But obviously it explains why we play 24-board sessions so often, doesn't it? Errmm...

[Zelandakh]

24 is a special number in many ways.

[gwnn]

I checked that site after I posted but I think my fact is still the most interesting (unsurprisingly. ).

[Zelandakh]

I found "the kissing number in 4-dimensional space" the most interesting. Perhaps we can agree now that when we start playing bridge in 4-dimensional space we will also use 24 board sessions.

[gwnn]

Fair enough, I admit to me it is close between the two. Didn't we start playing in 4D space in 1905 though? I never knew about the kissing number controversy in 3D, it's quite fascinating that people couldn't answer this for such a long time!

[ArtK78]

Pardon me if I put a damper on the 24 craze, but when I first started playing I frequented a club that played 11 2-board rounds, resulting in a 22 board movement. It also resulted in a 10 top which is easy to deal with.

[barmar]

shevek, on 2012-October-18, 03:41, said:

Given normal rate of play, a "standard" bridge session is around 3 hrs.
13 rounds x 14 minutes = 182, 9 x 20 = 180, 7 x 26 = 182.

Around here the typical round times are 15 minutes for 2 boards, 21 for 3 boards (the formula is 6 min/board + 3 min/round). Club games are usually 24 boards = 180 minutes, tournaments are usually 26 (or 27 if the section size requires 3-board rounds) = 189-195 minutes (plus one or two 5-minute hospitality breaks).

A year or two ago I played in a side game on the last day of the NABC. We had 5 tables, and they made it a 5-table Mitchell with 5 board rounds. I guess by this time in the tourney the directors were getting really tired, and didn't want to deal with setting up a Howell.

[Zelandakh]

ArtK78, on 2012-October-18, 06:59, said:

Pardon me if I put a damper on the 24 craze, but when I first started playing I frequented a club that played 11 2-board rounds, resulting in a 22 board movement. It also resulted in a 10 top which is easy to deal with.

The club I sometimes play in does this too most of the time except that a top is 20. The 24 stuff was just fun!

[Phil]

In our open pair games, 27 boards (9-12 tables) or 26 (13 to 17) are the norm. I run my games with 15 or 22 minute rounds. Our junior games are 21 to 24 boards, and they are given a little extra time.

I know in the UK you have the concept of the 'host' so you never have half tables, right?

In team games, 24 is typical, because of the extra time for reporting.

[gordontd]

barmar, on 2012-October-18, 07:01, said:

Around here the typical round times are 15 minutes for 2 boards, 21 for 3 boards (the formula is 6 min/board + 3 min/round).

I usually use 7 mins a board + 1 min a round. Still give 15 for 2 boards, but 22 for three.

[Vampyr]

shevek, on 2012-October-18, 03:41, said:

A pure all-play-all contest - Mitchell or Howell -
requires 13 x 2, 9 x 3, 7 x 4, etc.h sessions that play 30 boards, spanning lunch. Say 11am - 3pm.

You can't have an all-play-all movement with a Mitchell.

Phil, on 2012-October-18, 08:49, said:

I know in the UK you have the concept of the 'host' so you never have half tables, right?

That is not true. A host cannot fill a half table by himself, can he? Hosts are not there for filling up tables; they are there to accommodate players who have come without a partner.

Quote

In team games, 24 is typical, because of the extra time for reporting.

Bridge Mate II is the answer to the extra time. You get your next assignment electronically, so you don't have to wait for the assignments to be posted on the wall or wherever.

Of course, in some small clubs you might have to actually score up and take the scoresheets to the scorers. That takes ages.

[gordontd]

Vampyr, on 2012-October-18, 14:42, said:

A host cannot fill a half table by himself, can he? Hosts are not there for filling up tables; they are there to accommodate players who have come without a partner.

Unless you have three hosts, as some clubs do. But even then you can end up with a half table when three players come without partners and refuse to play with each other.

[Vampyr]

gordontd, on 2012-October-18, 14:45, said:

Unless you have three hosts, as some clubs do.

Yes, of course, but I will go out on a limb and suggest that three hosts is not the norm.