For those who are paying members and love backgammon please send me a request to join my fellowship and play in our gammon games tournaments beginning May 15th. It will be done with triple gammon rules for these tournaments. Thanks.

Big Boss of Brian's 1971 Pub.

furbster: that's why i love cloning backgammon, since that happened :-) ...a chance till the end :-)

speachless: cloning gammon is definitely different you can have bore off all but one piece and lose the game horrifically!

Lightbug: cloning backgammon in my opinion :-) and very different from backgammon, followed by crowded backgammon...

Lightbug: Is Nackgammon different enough from Backgammon to play?

If you're good at Backgammon then you'll start appreciating the differences after a few matches. If you're still very much learning Backgammon then the unfamiliarity of Nackgammon probably won't make that much different over the unfamiliar aspects of Backgammon.

What do you think the best backgammon variants on this site are?

Is Nackgammon different enough from Backgammon to play?

Does Anti-Backgammon have much of the same depth as Backgammon?

How about Fegva and Plakoto? Grasshopper?

moistfinger: Thanks, but that's not the problem It's a bug

pgt: In the first page you get to when you create a new game make sure you 'untick' the 'Include unrated players' button which in always pre-ticked, only then will your upper and lower BKR filter work.

playBunny: In your example, what would a single game be worth and also a fifteen game match with these same two players?

What does 4 * Sqrt mean? Four times the square root of something? The match length? Yes 4 × √5 = 8.94. OK, so for a single game it'd be 4 rating points divided up by a formula figured out from the players' ratings? Since 4 × √1 = 4? And for a 15 game match, 15.49 ratings points 4 × √15 = 15.49? Interesting, and this is a weighting scheme. I am thinking that the difference in the players' ratings is a fairly accurate way to determine the percentage of points awarded from the match weighting as it is used here, though without the match weighting. This is not quite how I was thinking of weighting it, but it seems like a good plan and is lots better than what we have now.

This method seems to make the length of a match much less important to the higher rated player than the method used here. Or am I imagining this?

playBunny: quote "The real question is: why do the same points apply when you win or lose an 11-point match or 1-point match???"

I have wondered about this. As I used to only play single games, the rating system here would discourage people with higher ratings than myself from playing me. When I started to play matches, I noticed that higher rated players were more likely to play me, but only if we played longer matches. I presume this was in part to account for the skill supposedly shown by the higher rating and the rating awarded for winning the match.

So I got to thinking, why doesn't Fencer have a weighting system for the matches? With a single game being lessened the most and then a steep curve that begins to level off as the number of games in a match increases?

An example; It seems like a 100 point difference in rating has the rating change 11 for the person with the lower rating if he wins and 5 if he loses. Seeing how even the world champion can be beaten in a single game it is obvious that such odds are ridiculous for a single game, but certainly seem fair enough in a 15 game match. How hard can it be to devise a scale for the odds and ratings to make it worthwhile to play with anyone?

As I only play on this site, I have to wonder if the other sites you've mentioned playbunny already do something along these lines?

playBunny: Thank you for your comments erudite rabbit.

pgt: ~~ I am definitely setting up 2200 as minimum. But there is always one (and only one) player who manages to accept the game with less than 2100 rating! It must be that the site isn't working. Since it first happened I have been VERY careful to check, and it has happened twice more.

Yes, I thought it was too much to hope that it would be as simple as "not plugged in". Thank God there are Reshers in the world, eh? ;o)

~~ As for points - it always seems to me that in a simple game, you get the same points whether you just win, or win with a gammon, or win with a backgammon. That's rubbish.

That's how it works with proper backgammon, ie. the version of the Elo formula that FIBS, DailyGammon and various other sites use. It's getting to the match length and the win that matters./ How you do it doesn't count. Same as in tennis or other sports. You may get a pat on the back for winning by a country mile but you don't get any more of a win.

~~ As for "match", in super-rugby, the losing team can still get bonus points for scoring 4 tries, or for losing by less than 7 points. It seems to me that if you lose an 11 point match 11-0, then you should not be rewarded, but if you lost 11-10, you should still lose, but perhaps lose 2 points instead of 8. (But it's only a game)

Ah, that's interesting. Sounds like we need super-backgammon! :-D

I had been going to say that rating points aren't in any way a reward, even if it's nice to get them, but that they contribute to a rating which is intended to be predictive - that is two ratings will give you each player's winning chances in a match between them.

That's still true (for the proper formula but not for the BrainKing version) but I was then going to say that it's match wins that go into the formula and give you those percentages and the games don't matter. However, I had second thoughts. Why, indeed, shouldn't 11-10 count as less of a win than 11-0? After all, it's reasonable to at least suspect that the player who scored 10 knows a bit more about the game than the one who scored nothing.

I think the answer is that the backgammon formula, based on matches, is nice and concise as it is but could become rather complicated if it tried to take into account the games as well. I'm no mathematician so I don't know what would be required but it would certainly be more complicated with both scores involved rather than just the binary won/lost. It's not even certain that it would be more predictive. Mind you, once you had such a game-based formula (and a large number of matches), it would be straightforward to test.

It's certainly an interesting idea.

.

Getting back to that win/gammon/backgammon. It really depends on whether you're playing a money game (where the final score actually matters because it multiplies the stake; so a backgammon win in a $10 game would therefore be worth $30) or whether you're playing a 1-point match, in which case the extra 2 points are superfluous.

It matters because if you win a gammon or backgammon in a 1-pointer then you've possibly played badly. Gammons and backgammons are usually achieved through taking risks that reduce your winning chances. As such they get flagged as errors by analysis. If you only need 1 point then you should play to win 1 point and not more. (If it happens by chance that's fine but no extra risks should be taken). I therefore wouldn't give credit for exceeding the match length, whether it's a 1-pointer or a 25-pointer. But a money game is arguably worth more. That rating formula that takes games into account might also be able to treat money games differently rather than as 1-pointers.

playBunny:
I am definitely setting up 2200 as minimum. But there is always one (and only one) player who manages to accept the game with less than 2100 rating! It must be that the site isn't working. Since it first happened I have been VERY careful to check, and it has happened twice more.
As for points - it always seems to me that in a simple game, you get the same points whether you just win, or win with a gammon, or win with a backgammon. That's rubbish.
As for "match", in super-rugby, the losing team can still get bonus points for scoring 4 tries, or for losing by less than 7 points. It seems to me that if you lose an 11 point match 11-0, then you should not be rewarded, but if you lost 11-10, you should still lose, but perhaps lose 2 points instead of 8. (But it's only a game)

pgt: When I set up a Hyper game and say minimum BKR 2200, how come a player with a BKR of 2056 is, consistently, able to accept the game.

Either the site isn't working or it's operator error. The "Are you sure it's plugged in?" question here is "Are you definitely setting it up with 2200 on the left and 4000 on the right?" ;-)

I don't really enjoy playing a game where I stand to win 2 points and lose 12, but such is the ridiculous rating system that that's what happens.

I hear ya, bro. I feel your pain. (Well, I do when I lose ;o)

While I'm on the band-wagon, why do the same points apply when you win or lose an 11-point match 11-10 or 11-0???

The score is for the match, not the games in it. That's just part of what "match" means. The real question is: why do the same points apply when you win or lose an 11-point match or 1-point match???

When I set up a Hyper game and say minimum BKR 2200, how come a player with a BKR of 2056 is, consistently, able to accept the game. I don't really enjoy playing a game where I stand to win 2 points and lose 12, but such is the ridiculous rating system that that's what happens. While I'm on the band-wagon, why do the same points apply when you win or lose an 11-point match 11-10 or 11-0???

pgt: Five years? Luxury! I'm on 8½ so far and I've got Slowlaughs2 who I suspect is their king, though I must admit, Slowpol is definitely in line for the throne. ;o)

pgt: LOL ! So true. It's always best to avoid tournaments for that very reason. Quite a few players get it arseways and think the point of games is to wait until the very last hour before timeout to make a move.

"....slowcoaches who will keep you tied up for a year or two." Try FIVE YEARS!!

diemen54: Join this tournament .. Small & quick elimination tourney #203 or any of its kind .. Small & quick elimination tourneys .. plus any of the games here .. WaitingGames

Why that tournament? Because you only get to play one tournament at a time and that one will be fairly quick. The last thing you want to do is join a long tournament with one of the site's dozen or so slowcoaches who will keep you tied up for a year or two.

ho like tu play I am new here and dont now how at works

Thom27: thanks for the advice Thom, i didn't realize that, good to be aware of that. the issue is solved now.

speachless: Please always give the move number in such cases, so that the situation in question can be easily found later, when the game has been played on.

Aganju: OK thanks, so i guess it's a single error. Hope the admins here will react, no answer since 3, 4 days...

speachless: I don't see a reason why bar-5-7 would not be a perfectly legal move for white.

Hi
i'm the meaning this is an error. in the game bellow the system wants me to move 1-6 and 5-7. But I wan't to move bar-5 and 5-2 but the system forces me to move 1-6 / 5-7.... Is this an error?

I'm asking 'cause usualy when a game has an error i only need to contact fencer and he deletes the last roll or whatever, but i didn't get an answer since 2-3 days... so am I maybe wrong and it is not an error?

Cloning Backgammon (speachless vs. ljubisa popovic)

thanks for your support...

coan.net: very good point as well. Based on your question as well as playbunny's comments, it seems my most recent scenario that I posted does not qualify for the rule in question.

cd power: Are the "official" rules for the game somewhere on the internet? Just kind of curious on the different "interpretations" of that rule.

For example, in the game - lets say that ALL your pieces except for 1 is already past the prime on the "1" space on the bottom of the board, and only ONE piece is trapped by the prime - would you still interpret the rule the same way?

".... but if opponent has collected all his checkers onto the one point behind player's prime, the player must unblock a point in his prime to allow the opponent a chance to move."


***Update - I started to post this before I seen the previous 2 posts ****

playBunny: I think this is the best response I have read on this topic. Thank you

Carpe Diem: I'm involved in a game where all of my stones but one are behind a prime - the other stone is on my 1 spot, so also can't be moved. I would think the spirit of the rule would mean that my opponent should unblock, but since I haven't collected ALL of my checkers behind his prime, I can see how a literal translation would suggest that he doesn't need to unblock. Does anyone know with certainty how this should be handled?

The same rule is given on Backgammon Galore as "Limitation on primes: You may not build a prime (six consecutive blocks) in front of all of the opponent's checkers; at least one opposing checker must be in front of your prime".

The rule is about building a prime. So if a certain move would inappropriately complete the prime then it is illegal. The rule prevents the move in question.

The rule whose spirit you're suggesting would be about forcing a player to break a prime that's already been made. That's a very different thing and may not actually be possible at the point at which it becomes applicable.

The rule would be have to be something like "If your opponent cannot move and all their pieces behind the prime are stacked on the single point immediately behind then you must open a point within the prime at the first opportunity". This rule would force the given move or small set of moves that break the prime.

This is unlike the prevention rule in several important ways, as can be seen above. The similarity is that they are both concerned with not allowing a prime in their respective contexts.

To be honest I'm not sure what the spirit of the original rule is unless it's to give the trailing player more chances to prevent the prime happening in the first place. Each turn that the leading player cannot close the prime is an opportunity for the trailer to claim that point themself and retain a link, however tenuous, to the forward territory. Once the prime has been made then it's tough buns, they didn't make it.

I think a rule that extended the spirit of the rule as it appears to me would have to ban primes altogether - and that's quite a game changer.

Pedro Martínez: Again, it is the interpretation of the rule. I have one checker that was able to pass her prime (6 consecutive pieces) and has moved as far as possible, to the "1" on the bottom of the board. All other checkers are stacked on the 2... there are no possible moves to make at this point.

I think what you are getting at is that one checker was allowed to move as far as possible so now it is ok to block the rest, because the rule does not state "collected all [REMAINING] checkers..." so this is where different interpretations come into play.

cd power: Where exactly have you “collected all [your] checkers onto the one point behind [your opponent]'s prime”?

cd power: It's happened to me a couple of times and if they don't accept the rule I just stick them on myblocked users list.

Well, it happened again. I politely wrote and pasted the rule, but I guess she didn't understand me and wrote back to me in Czech (which I don't understand) and didn't comply with the rule.

Fevga (japajka vs. cd power)

Carpe Diem: i think it should be interpreted 'if you cannot move any more with any dice roll, he needs to open up'. But I have never played Fevga over a real board, so maybe someone who has should answer this.

There was some discussion a few weeks ago on the main Brainking board about this rule that isn't software enforced:

• It is allowed to build a prime (six consecutive blocked points) anywhere else (not in the player's starting quarter), but if opponent has collected all his checkers onto the one point behind player's prime, the player must unblock a point in his prime to allow the opponent a chance to move.

Pedro Martínez: Wow! And a pass too.

Gotta love games like this…
Hyper backgammon (Nyumi vs. Maxxina)

moistfinger: Program is wrong? ;)

Thom27: It seems we just have to accept the questionable dice rolling here. We may play here for fun, but for serious play one should go elsewhere.

That's not so. You have to accept it or go elsewhere. I, we don't have to do anything of the sort until you prove your case. It's like someone saying that they've see seen the Yeti but have no tissue sample, no photo, not even a map showing how to get to where you saw it. The Yeti may exist but it can only be treated as an interesting but unconfirmed story. Aganju claims to have met the Yeti and had a chat with it . That makes it more interesting but the story still needs more to become real.

moistfinger: The only truly dishonest and unnatural backgammon dice on the web is found on DailyGammon:

Lol. Now you've got me wondering which of the DailyGammon dice whingers you are.

Resher: thanks!

the opening roll can be used to predict your opponents roll in case your won or lost the first roll (i dont remember which)

I think the most helpful posts about the non-random rolls (including stats) were posted on this DB in July 2010. For example see:
http://brainking.com/en/Board?bc=26&bscx=1066337#1066337


The particular issue discussed there may have been fixed by now - does anyone know?

Re: taking advantage - I think I remember Nabla posting a set of opening moves that took advantage of the unusual opening roll distribution, but again - this might no longer apply.

Hrqls: You are of course right that statistics is required, but it is a) considerable work, and I don't want to bother if fencer seemingly is not interested anyway, and b) it is not always possible. One can't tell afterwards in which order the dice in different games have been rolled. So there is no way but recording during play. I once tried to create a tally sheet counting the equal and the different rolls when going from one BG game to the next, but I quickly lost track ... and see point a) above.

Ananju mentioned there is a way to reproduce the opponent's roll with higher probability than normal. This might be proven by analysing many old games, but if only few players know about this method and use it only in few situations, the statistical effect is very small and difficult to detect.

It seems we just have to accept the questionable dice rolling here. We may play here for fun, but for serious play one should go elsewhere.

moistfinger: I have played on Dailygammon for some time, and didn't notice any strange or unnatural behaviour of the dice. Also, they have documented their dice rolling, and this method, if implemented correctly (bugs are always possible of course) should give fair and statistically correct rolls.

Thom27: i always am fond of your second reason :) ... but you probably also know that humans tend to remember bad things more than good things .. therefore there always seem to be more bad rolls than good rolls

your third reason: i think i was the one who came up with that, and i did come up with it by counting all games and record in which the bug happened and also in which games it didnt seem to happen, after that i let some friends on here know about it to verify my thoughts, and after that i posted it on the board to ask for more statistics ...

to claim any random number generator is bad you need to collect statistics, without statistics you will only have your second reason and that one doesnt really count

so, could you please write down your games and keep the statistics (all games on this site remain here forever, so you can show it at any point in the future to everyone) .. once your have the right statistics we can discuss it for real

Thom27: Thanks for that. Overall I find the dice on Brainking to be quite natural, they feel random and honest enough; it would be nice to always win but that's not the way it goes with a dice game, however good a player one is. The only truly dishonest and unnatural backgammon dice on the web is found on DailyGammon: Play there for a week and you will come to cherish the odd dice idiosyncrasies on Brainking!

playBunny:
Аз не използвам никакви средства за влияние върху числата, които ми се падат на заровете, но веднъж на този сайт хвърлих поред първо дюбеш, а после дюшеш в края на играта и противникът се разсърди за това, че съм такъв късметлия. Разбира се, това може да бъде и просто случайно, макар и само с вероятност 1/1296.

Aganju: if the randomness is not good, it slowly makes a different game out of Backgammon - for example, if there are less doubles, or incorrectly often two doubles in a row, you can adjust your strategy to take advantage of it.

I suspect that any such effect would have to be quite sizeable for it to change people's strategy. Their strategy can be highly resistant to change even when you teach them to improve their game.

Aganju: It is still a fair game, but it is not 'standard' Backgammon anymore.

Aganju: However, I found a high chance of reproducing your opponent's roll by clicking in specific sequences. So when the game comes up, and he had a 5-5, and I want one too, I do that sequence of clicks, and have a higher-than-1/36 chance to get it too (it does not work all the time, but maybe 1:3; still, pretty useful feature); whereas if he has 1-2, I will not do that typically.

I'd say that if you're doing that then it's still standard backgammon but it's no longer a fair game. :-/

playBunny: You are right of course. It does not make it easier to win, if you cannot predict the 'bad' rolls. However, if the randomness is not good, it slowly makes a different game out of Backgammon - for example, if there are less doubles, or incorrectly often two doubles in a row, you can adjust your strategy to take advantage of it. It is still a fair game, but it is not 'standard' Backgammon anymore.

However, I found a high chance of reproducing your opponent's roll by clicking in specific sequences. So when the game comes up, and he had a 5-5, and I want one too, I do that sequence of clicks, and have a higher-than-1/36 chance to get it too (it does not work all the time, but maybe 1:3; still, pretty useful feature); whereas if he has 1-2, I will not do that typically.

Thom27: How, exactly, have you taken advantage of these issues with the dice?