Blackadder Mr K: That's one thing we all can agree on ;-)

Blackadder Mr K: Would you make the same statement regarding chess? Backgammon can be analyzed just as chess can -- only backgammon is more interesting (to me) because of the random factor. Personally, I don't have a lot of patience with analysis; but some folks enjoy it, and I understand why.

There's an easy way not to get tired of analysis -- don't read it!

Even that doesn't last long, and any given day can only be used once

With 1 day to move, he won't keep you waiting long!

You need to distinguish between childishness and playfulness! Trying to set a meaningless record can be fun at any age!

I think rather that the meaning is different . . . It's one thing to run a footrace, a different thing to run it with your feet tied together . . . I can imagine trying to set a record for the longest game. It would take some skill on both sides in order to achieve this. In fact, this might be a new kind of team game in which the players at the table are on the same team, with the same goal.

I won 13 straight from 21 Feb to 3 Mar and my rating improved dramatically.

Having a fairly high ranking at the moment, I find that most wins are worth either +8 or +1 to me,, with the dividing line somewhere around 400 points differential. Nothing in between. If the differential is even higher, I may get 0.
Losses are a minimum of -8, and may go as high as -25 or more. So - against the majority of opponents, I have to win 8 out of 9 just to breakeven!

SueQ: That's the glitch I mean. Based on my experience on other sites, it seems to require more than 1 software fix to get it working right, as it comes up in different contexts.

I wonder whether user input is solicited on what priority should be given to various improvements. There are one or two glitches in the backgammon engine that should be fixed first, but introduction of the doubling cube and matches of greater length than 1 would be right after that on my list.

:-) well, I'm glad to see I'm not just a grumpy curmudgeon, thanks for the information.

I would say that backgammon is also "not for people who don't like blocking games." The style of play should be dictated by the dice and the opponent's play, not by personal preference. In backgammon as in nack, you should always be aware of opportunities to block your opponent, and of the risk that your opponent will block you.

Grenv is precisely correct. This raises the question whether one who knows the rules should play by them, even when ignoring the rules gives him a better outcome.

I have gone both ways on this question, but lately I have decided to make the "really" correct move, rather than the move that is legal only in "brainkinggammon".

"Backgammon" is not mostly luck, or there would not be players with ratings as high as yours! An individual game of backgammon can be determined by the dice, but a player's overall success -- such as is shown by his rating -- is determined entirely by skill. In other words, since in the long run luck is the same for everyone, a player's RELATIVE degree of overall success has nothing to do with luck and everything to do with his or her ability.

The paradox is that, if both players know their doubling cube strategy, doubles are accepted more often than not. It's easiest to explain why in the context of a money game; there are additional considerations in a tournament match that we can discuss later.

When playing strictly for money, each game stands on its own. The players agree in advance how much money they will wager on each point. Say they play for $2 a point. Then a simple game is worth $2 to the winner. A gammon is worth $4, as is a doubled game. A doubled gammon is worth $8, and so on. (This can get expensive!)

OK now, suppose we are playing for $2 a point. After a while you think your position is so good that you have a 70% chance of winning the game (nothing in backgammon is certain!). You properly turn the cube to 2 and offer it to me.

Now, here is what I am thinking. "If I drop the cube right now, I will lose 1 point, or $2. Dropping will cost me $2, so dropping is worth minus $2 to me. On the other hand, if I take the cube, I will have a 70% chance of losing $4. However, I will also have a 30% chance of winning $4! The value to me of accepting the cube is therefore 0.70 x (-$4) + 0.30 x (+4) = -$2.80 + $1.20 = -$1.60. Since minus $1.60 is better than minus $2, I should take the cube even though I only have a 30% chance of winning!"

Now, you might ask how the game can have a value of minus $1.60, when I know for sure I will either win $4 or lose $4. Think of the minus $1.60 as the average result that you would obtain if you played many games against this same opponent and always accepted the cube when it was offered to you when the winning odds are 70-30. If you encountered this situation 100 times, you would expect to win about 30 times and lose about 70. Your net loss would be ($120 - $280) or $160. A loss of $160 over 100 games works out to $1.60 per game.

Note that if you dropped the cube every time, you would lose $200 or $2.00 per game.

Of course, if you and your opponent are evenly matched you should also encounter the reverse situation 100 times, where you get ahead, double at 70-30 and he accepts.

At the start of the game, the doubling cube belongs to neither player, and either can make the first double. Physically, the cube is usually placed on the side of the board, midway between the two players, with the "64" facing up.

Doubling strategy, I might add, is probably the most difficult part of the game.

As long as a match consists of a single game, there is no reason to use a doubling cube. What you may be overlooking is that it is rare in real life to play backgammon for just one point. In tournaments, matches are played for a set number of points, which can be any number from 2 to 25 or even more. So, if you are playing an 11 point match, the first player to score 11 points wins the match. Each game starts with a value of 1 point, and the simplest case is that the winner of the game gets 1 point. A gammon is worth 2 points, however, and a backgammon is worth 3. Finally, if the game has been doubled one or more times, the winner's points are multiplied by the current "value of the cube", i.e., 2 if it has been doubled once, 4 if twice, etc. It's quite possible to play an 11 point match in 1 game in this way; alternatively, an 11 point match could last as many as 21 games!

A doubling cube is an object used to record the current value of a game that has been doubled one or more times. It's shaped like a die and has the numbers 2, 4, 8, 16, 32 and 64 on its six faces. A player who wishes to double the value of the game picks up the doubling cube before he rolls his dice, and offers it to his opponent with the side labelled 2 facing up. If the opponent accepts the double, he "owns" the cube and places it on his side of the board. The owner of the cube can choose to double at any later time when it is his turn, before he rolls the dice. He would offer it to his opponent with the "4" facing up. The original doubler then owns the cube, and can double again on his turn, and so on.

Here is an explanation of the doubling cube and of gammon and backgammon from Backgammon Galore!

I forgot to mention in an earlier post that multipoint matches would require the system to recognize gammon and backgammon as well.


Doubling
Backgammon is played for an agreed stake per point. Each game starts at one point. During the course of the game, a player who feels he has a sufficient advantage may propose doubling the stakes. He may do this only at the start of his own turn and before he has rolled the dice.
A player who is offered a double may refuse, in which case he concedes the game and pays one point. Otherwise, he must accept the double and play on for the new higher stakes. A player who accepts a double becomes the owner of the cube and only he may make the next double.

Subsequent doubles in the same game are called redoubles. If a player refuses a redouble, he must pay the number of points that were at stake prior to the redouble. Otherwise, he becomes the new owner of the cube and the game continues at twice the previous stakes. There is no limit to the number of redoubles in a game.



Gammons and Backgammons
At the end of the game, if the losing player has borne off at least one checker, he loses only the value showing on the doubling cube (one point, if there have been no doubles). However, if the loser has not borne off any of his checkers, he is gammoned and loses twice the value of the doubling cube. Or, worse, if the loser has not borne off any of his checkers and still has a checker on the bar or in the winner's home board, he is backgammoned and loses three times the value of the doubling cube.

And, of course, multi-game matches to go with it -- preferably with an option to select how many points to a match.

Anyone had any thought about how CBG strategy differs from regular BG? My early thoughts -- having only started a number of games -- are that there is a great advantage in seizing 3 or more points in both your own home board and your opponent's as early as possible. It can be very constricting to still have 3 or 4 checkers on the bar while your opponent holds 3 or more points in his home. While in BG it can be a disadvantage to make your own 1 or 2 point early in the game, the extra checkers available in CBG may make that less of a consideration.

More so even than in regular BG, the emphasis is on position. I have been slotting strategic points -- especially the 5 and 7 points on both sides -- more aggressively.

I have yet to fully understand the implications of being able to build a prime and still have 8 checkers left over. I will probably learn more about that as the games I am playing progress. A related point I will be watching closely is whether it makes sense to play a massive backgame, with 6 or 8 checkers (or even more) deep in the opponent's board. Timing will need to be relearned from scratch, I think, in light of the additional pipcount available.

I moved the message I posted here a few minutes ago to the Crowded Backgammon discussion board -- I didn't realize there was one!