wetware: Pip count 521 - 340.

Nothingness: they way it seems to be worded i could feesably end up with an infinite amount of pieces to bear of my bar.

No, that would require an infinite amount of moves. But you're always complaining your opponents move only a few times a month, so while the number of pieces on your bar may grow, you don't live old enough to get an infinite amount. Now in theory, the maximum number of pieces on the bar is unbounded.

Nothingness: So, you're one move away from checkmate, and you double the stakes. Your opponent resigns instead of accepting the double. Didn't really change the outcome, did it?

grenv: Oh, it's not just anti-backgammon. That tournament has dozens and dozens of unfinished games, all-most all of them involving one of the players of the game I posted a link to.

Czuch: There's also this one. Started a year later (Oct 2006), but it's the first game in a 3 win match.

grenv: Ok, but if you take out the doubles, there are only 30 possible rolls

But why do you take out the doubles? The second player can roll a double, so the second player has 36 different rolls. 2 of them can match the rolls of the first player.

pgt: Of my current open backgammon games, 6 out of 10 had identical rolls for both players.

grenv: No, expected would be 1 in 18. The first player doesn't roll a double, which means that out of all the 36 possible rolls of the second player, only 2 match the roll of the first player.

lukulus: These games are played without cube so I think it isnt be possible to play it as triple gammon.

Currently, all triple gammon games are played without the cube. So the fact there doesn't exist cube variants for Plakoto and Fevga shouldn't imply there can't be triple gammon tournaments for them.

Thad: No such button is needed. Currently you have the option to have the move list displayed next to the game. Every move is clickable. It's already possible to view a game move by move (ply by ply even).

playBunny: Well, I imagine a programmer could implement autoplay in such away that if players A and B are playing, both have one man out, and A likes to mindlessly push buttons while B is a real player, one each turn, A pushes a button, B move is played automatically, and it's A's turn again. Repeat until B has two men out.

Of course, in the case of Ludo, it may be that the computer plays an entire tournament, never encountering a play where a player actually has a choice.

playBunny: Skill only plays a role if you have at least two men out. Most of the time, you just have zero or one men out - in all these cases, the play is forced, requiring no decision of the player. Until BK offers a full autoplay, I won't be playing Ludo.

grenv: And not only that, autopass only works if your opponent doesn't insist you mindlessly push buttons.

I am not really that interested in averages. I've encountered players that will maintain a high average, but still move slowly. Some people play games of one type rapidly, and of another type only when they're about to run out. Or they find the time to play 5 anti-backgammon matches in a day against their friend, and don't bother moving at their other games. High averages, but you don't really want to play them.

I propose the following statistic: given a game G a player has to move on, let T_G the time it has been the players turn. (So, if today is Dec 27, and his opponent has last moved on Dec 24, T_G is 3 days). Then let T_max the maximum of all T_G's of a player. A high T_max means the person is moving slowly in at least one game at the moment. If his T_max is close to when he last made any move, he's probably on vacation, or otherwise unable to play. If there's much difference between T_max and when he was last active, he has too many games running then he can manage.

Thad: You are wrong.

The chance of rolling exactly 10 doubles in 45 rolls is (1/6)^10 * (5/6)^35 * C (10, 45), where C (x, y) gives you the number of ways to pick x elements from a set of y elements. Rolling exactly 5 double sixes, and exactly 5 other doubles out of 45 rolls happens with chance (1/36)^5 * (5/36)^5 * C (5, 45) * C (5, 40).

The former is slightly less than 9%, the latter is slightly more than 0.1%.

In this game I first have to move my checker on 1 past my opponent's starting point. I roll 6-3; either 1-7 or 1-3 would move my checker past the opponent's starting point.

Yet the system doesn't allow me to play 1-3, insisting I play 1-7. Am I missing a rule, or is this a bug?

On brainking.info, Fencer says that he plans to three games that make up Tavli. Portes is one of them, and he says Brainking has it already, because it's just backgammon without the doubling cube. That's not quite correct. The rules of Portes state that the winner of the opening roll rerolls. A subtle difference, meaning that the player going first may start with doubles, which is impossible in regular backgammon. (There's also a slight difference in counting points, but that's only relevant for point matches).

Of course, it means that implementing Portes will not be difficult, as it's almost the same. Just not exactly.

Carl: Yeah, I checked my settings - it was disabled (I guess that when a new game is added, everyone "autopass" settings for that game is set to disabled, even if the player prefers to play with autopass). I had turned on the "Select this option if you want to use auto pass" when creating the invitations, but I guess that was silently ignored.

Has autopass been implemented for Plakato? I'm playing 15 or so games of Plakato, and none of them seem to have autopass enabled; but I do not know whether that is because Plakato is in the class of games that do not have autopass, or whether that's because none of my opponents have autopass enabled.

jryden: I ain't going to disable my autopass - the rare occassions where I do get an opponent that has autopass enabled, I don't want to lose.

And I'll continue to delay moving in an autopass situation when my opponent hasn't enabled autopass - I marked all days in December as vacation days for no other reason to not have to move in a hand full of games where all I can do is pass, but where my opponent insists on me pointlessly hitting a button.

AlliumCepa: Had both players turned on autopass before the game started? Otherwise, it won't work.

playBunny: If the scoring of the game is such that gammon or not doesn't matter (for instance because the dice is not being used) playing on to see whether you could avoid the gammon doesn't make much sense. Your play might be to avoid th e gammon, but since gammon or not doesn't matter, your opponents play will not take gammon considerations into account. With other words, you would be both playing a different game. Even if you avoid the gammon, it does not mean you would have avoided the gammon if the gammon had mattered (because your opponent might have made different moves).

DarwinKoala: I usually resign when I feel I've no chance left; not just with backgammon variants, also with other games. I don't go out of my way to calculate the chances, so I may play on for a move or two "too long", but whenever it's obvious, I resign.

And I greatly appreciate it if my opponents do so as well.

I'm wondering, what's the record amount of stones in a cloning backgammon game? I'm currently playing a game that has 57 stones (33 vs 24) on the board, and there's still the possibility that more will appear.

Hrqls: It would be 10/36 * 10/36 if all you want is exactly one 1 on each of the two rolls. But if you want at least two ones in two rolls, the chance is 1/36 + 10/36 * 11/36 + 25/36 * 1/36 == 171/1296 == 0.132. After all, you should consider rolling two 1s on either the first or the second roll.

fakar10: Over a year and a half old.

nabla: Triple gammon is not more a different game than backgammon as cubed backgammon is. And we don't have a different rating for them either.

Fencer: Questions: 1) How does Anti-Backgammon in triple gammon score? 2) I just created a triple gammon tournament - and (as standard) it sets the final game to be a three win match. How does that work in triple gammon?

Fencer: 1% of the code deals with draws? ;-)

Hrqls: And to get rid of fractions, 0, 1, 3, 5 as scores work as well as 0, 0.5, 1.5, 2.5.

It reminds me a bit of 'streetsoccer' as played on littlegolem and mastermoves. There the winner/loser scores can be 5-0, 4-1, 3-2 and 2-2. (5-0 for a win without overtime. 4-1 for a win in overtime. 3-2 for a tie with goals - winner is the person scoring last. 2-2 for a goalless game).

Hrqls: What is the point of scoring 0.5 for a loss?

nabla: I think cubed matches are treated the same way as multi-game matches in other games. And there a time-out only times out a single game.

But I agree, it would be nice if you can offer a resignation for a certain amount of points. For the user interface, only three options need to be offered "resign with backgammon", "resign with gammon" and "resign". If a backgammon, or a gammon is not possible, those options don't need to be offered. And an opponents confirmation is only required if the choosen resignation isn't the highest possible.

Separately, it would be nice to have the option to resign the entire match - not just for backgammon, but for all games.

Andersp: Ah, yes, I thought it was you, but I wasn't sure and that's why I didn't mention a name.

Anyway, if I were to ever make an offer in the form "I'll buy a black rook (or two) if you implement this-and-this", I'm sure to write down an exact specification of the feature. ;-)

nabla: Whether that's the only "unfair" thing I cannot say. I leave that judgement to the person who paid for a black rook to get autopass. I would feel cheated if I were that person.

Note that autoplay has been half implemented for years already: if for instance in chess, you click on a piece that can only move to one square, the game automatically moves it to that square. And you don't even have the option to prevent your opponent to use this feature.

grenv: Problem is that Fencer doesn't think it's "broken" and needs fixing. Something has been implemented and is labelled 'autopass'. It just doesn't match what others think should be called 'autopass'.

A few weeks ago, a new gamesite opened. It doesn't have many games yet, and it won't implement backgammon (because it wants to implement games you don't find anywhere else), but it does have autopass/move. And you don't even get the option of performing mindless clicking. If you don't have a choice to make in a game, you don't have to click.

Andersp: I would use autopass if one of my opponents would actually let me.

So far they don't (which means I won't move in their games until I'm about to time out; don't expect that 21-point cloning backgammon tournament to finish for the next couple of years...)

nabla: 4 checkers, of which 2 are race checkers and 2 "get-off-the-bar-first" checkers. It's easy to see, the race checkers are black with a tiny light edge, and the other checkers have tiny light edges and are black otherwise.

Fencer: Ah, good. I presume that the new rule is in effect immediately even for running games? Or do running games keep using the old rules, which didn't enforce maximum die usage?

jolat: Indeed, there's no cube on this site. The reason is that it isn't implemented - a Fencer decision. ;-) At some, yet unknown, time in the future, a backgammon version with a cube will be implemented.

Some put a line on top of this page with the message that cubes will be implemented in the future.

redsales: http://www.bkgm.com/rules.html

playBunny: Some rule are conceptual ones, perfectly capable of being held in your head without requiring you to see them in print or on a web page.

Sure it can. And anyone can think of any rule, hold it in its pretty little head, and accuse others of cheating if they don't confirm to the rule. And then ask others to show them the rules that allow this behaviour, as you asked Anders. Here, this is what you wrote: She made an illegal move which is against the Brainking rules. Please, feel free to show me the bit where it says you can use just a single dice if it suits you.

playBunny: My point? You were claiming Brainking rules were broken. I was asking you to quote the rule being broken. Which you didn't (couldn't since there isn't such a rule).

playBunny: Ah, so we agree the requirement to swap your dice if that's the only way to be able to move from both dice isn't in the rules.

playBunny: She made an illegal move which is against the Brainking rules.

Which rule would that be? Care to quote the relevant portion from the rules pages that says you have to swap your dice if that's the only way to be able to move with both dice?

Please, feel free to show me the bit where it says you can use just a single dice if it suits you.<br>
There isn't such a line in the rules, and there doesn't have to be. However, there's nothing at all in the rules that forces you to move with the second dice first if that's the only way to be able to move from both dice.

There's no mismatch between the rules on the rules page, and the current implementation of the game.

alanback: But I specifically picked the infinite game to be a game with each site having 1 stone left, and both sides throwing 1-1s. Could you given a specific example of a position occuring in that infinite sequence where throwing 1-1 leads to the shortest way of finishing from that position?

alanback: The method you describe will produce some duplicates.

Really? Care to give an example of such a duplicate?

grenv: Once you have an infinite game, it's easy to construct an infinite number of finite games from it. Do that as follows: number your games 1, 2, 3, .... For game n, the first n moves are the same n moves from the given infinite game. After the n moves, pick the shortest sequence that finishes the game.

grenv: One piece all works as well. Put them anywhere on the board, under the condition they still have contact. Now let them roll only 1-1s. Neither side will be able to bear off.

Chessmaster1000: How do you conclude that.......?

Trivial. Suppose you don't get an infinite number of finished games. Then there should be a finite number. Take the one which took the most moves, say R moves. But then your finite set of games didn't include the game that finished after R + 1 rolls of 5-5 by both sides. So, the assumption that there are a finite number of games is false.

Chessmaster1000: You got it wrong. In the limit, the chance that you roll 5-5 "for ever" goes to zero, that's right. So, the chance for an infinite long game is zero. But that's not the same as an infinite number of games. Here is how it goes:

Take the following position: both players have 13 pieces off. White has its two remaining pieces on his 6 point. Black has its two remaining pieces on white's 5 point. White to roll.

If white rolls 6-6, the game is over. Call this game 1.
For game two, white rolls 1-1 (can't move). Black rolls 1-1 (can't move either). White rolls 6-6. End of game. This is game 2.
For game 3, the sequence goes: white rolls 1-1, black rolls 1-1, white rolls 1-1, black rolls 1-1, white rolls 6-6.
Or more general, for game N, both white and black start with N-1 rolls of 1-1 (this chance is not zero), and then white rolls 6-6.

Say there are a finite number of games, call this number M. But that could not have included a game that reached the position I described above and then continued with M rolls of 1-1 on both sides, followed by a roll of 6-6. Ergo, there's no limit on the number of different games.