gogul: The rating system applied to Ludo - that sucks more than with backgammon!!

Andersp: Apparently happy with the rating system yet somehow desperately complaining about the high rated players!

gogul: LOL...yes..i just checked his profile...but he also consider himself being a top player in backgammon :)

Andersp: playBunny plays Ludo on here, I tend to believe he doesn't care much about the Fencer system.

playBunny: at least one who is happy with the Fencer's system :)

Andersp: No, it works fine having one site for you lot and another, sophisticated, site for us.

playBunny:  Do you think it would be a good idea to have one rating for you sophisticated players and one for us who play any player?

Andersp: i think the BKR system should be more fair if all players played low rated players too

If there's a proper rating system put in place then you'll find a couple of players who prey exclusvely on the low rated players. Will you complain then as well, at these rating manipulators?

alanback: IMHO there are exactly three points that should be fixed in order to make a great backgammon site out of BK, where the experts would love to play :

1) Autopass and autoplay, regardless of the settings of the opponent, and which can trigger one way of the other even when cubing is an option.
2) A fair rating system.
3) A working .mat export.

2) and 3) are really easy to implement. The .mat export is almost done but still has an annoying bug, as for the rating system, adapting the BK rating system is just as easy :

A) Before putting the rating difference into the BK formula, multiply it by the square root of the match length (and then divide it by 5 if copying the FIBS formula, but that is not essential).
B) After calculating the gain or loss in rating, multiply it by the square root of the match length (and divide it by 5 if wished).

coan, you are right that Fencer might recalculate all ratings if he changes the rating formula, which needed a downtime the last time he did it. If he does it, I bet that I will lose my #1 spot to XXXXXXX (the unnamed computer user).
But frankly, I don't really care whether he does it or not. One way or the other, once the system is corrected, the ratings will converge to their accurate values in the long term, and what I care about is the long term.

Andersp, you are wrong in thinking that the problem lies within the higher-ranked players playing between themselves. Actually, the surest way to exploit the current rating system is to play 21-pointers against low rated opponents, when one wins non negligible rating points with almost no risk.

Andersp:  If it is seen as a problem that higher rated players don't want to play
against lower rated players, then one solution is to improve the
ratings system.  The BKR system penalizes higher rated players harshly for playing against lower rated players.  A properly designed ratings system should not discourage higher rated players from playing against lower rated players, as the BKR system does.  Of course, the higher rated players should always prefer longer matches.  

alanback: I dont think that i am so sophisticated, but i think the BKR system should be more fair if all players played low rated players too 

Andersp:  Only sophisticated enough to know that the BKR system doesn't work well for backgammon :-)

Czuch:  I should have said, "between players of equal rating".  In other words, if match length is the only determinant, then longer matches produce larger adjustments, since the skill factor is greater in a longer match.

Your observation about the effect of a likely win is what I meant when I said

"Where there is a difference between player ratings, the positive
adjustment from a win is greater for the lower-rated player than for
the higher-rated player.  Conversely, the higher-rated player suffers a
greater negative adjustment if he loses than the lower-rated player
would."

alanback: Thanks for the "links" :)...are you a sophisticated backgammon player?

alanback: Between players of equal strength, the longer the match, the greater the point adjustment.


I would think just the opposite, since the longer the match, the more likely the better player would win, and a likely win should correlate a lesser point adjustment?

Andersp:

http://en.wiktionary.org/wiki/sophisticated

http://en.wiktionary.org/wiki/backgammon

http://en.wiktionary.org/wiki/player

Czuch:  Using the FIBS formula as an example, because it is widely accepted, there are two variables -- match length and the difference between player ratings.  Between players of equal strength, the longer the match, the greater the point adjustment.  Where there is a difference between player ratings, the positive adjustment from a win is greater for the lower-rated player than for the higher-rated player.  Conversely, the higher-rated player suffers a greater negative adjustment if he loses than the lower-rated player would.

Longer matches produce smaller point adjustments if the higher rated player wins, but larger adjustments if the lower-rated player wins.

nabla:  In my view, assigning a project a priority so low that it never gets done is the same as refusing to do it!  Obviously I believe it deserves a higher priority, since the site is crippled as a backgammon site without it.

If you read playBunny's profile and see the reference to Dailygammon, you might wonder why the average quality of play here is relatively low.  I think an important reason is that many good players won't play under the BKR system.

The ◙ The Gammon Cube ◙ Fellowship is still looking for 2 more players to join our Grasshopper Team Tournament - so we can join the upcoming site team tournament.

If you are interested, please come and join our Fellowship & team.

Also: Fellowship is open to everyone - so even if you don't want to join the team, feel free to join!

◙ The Gammon Cube ◙

alanback: ..a new expression for me...exactly what does it mean?

Czuch: The latter makes more sense if you want ratings to represent a skill level, doesn't it?

nabla: It seems to me that the longer a match the more likely that the better player will win, so doesnt that mean that you should get less of an increase in your BKR for those types of matches versus a single game match?

Then again, in a single game match a win for a lesser ranked player should be considered more luck than skill, therefore they too should get less of an increase than if they won a longer match?

nabla: And just as a side note on the subject. If the time comes that Fencer does change the rating system, in the past what he had done when a change happened in the rating system was run every single game already played on the site through the rating system to get a new accurate rating..... so if he were to do it again, there is a chance that current games / matches be ran through to get the new rating.

So just a thought to keep in the back of your mind - even though it does not matter to the current rating system, if he were to make the change - there is a chance your current games would be taking into account for the future rating change.

Not that I know if he plans to do it or not - but I have always agreed that it would be nice if different games used different ratings systems... instead of all games be lumped under the Chess rating system which I think he uses.

alanback: When I talked to Fencer about that, he did not refuse to implement it, he sounded something like it would probably be a good thing, but of low priority. The priority might be higher if more people here would know that the present rating system is flawed for multi-point matches. So I am shouting it again : the present rating system is flawed for multi-point matches !

tonyh:  That's kind of a sore point for the more sophisticated backgammon players among us.  Nearly every other backgammon site has a rating system that reflects the reality that multiple point matches are a better test of skill than one-point matches.  However, Fencer has refused to implement such a system here.

Puckish: I would consider every specific advice over a certain move like "go, double now" probably breaking the rules and every general advice like "you all maybe should'nt play too conservative, we need a win to advance" perfectly acceptable. The former is just too specific, giving advice on a single move - and is not comparable to a golfer or any other sportsman for the reasons you gave yourself. The latter is simply a general advice about big-picture strategy, something every team should be allowed to discuss and agree upon. But that is just my "feeling" and others might draw different lines.

How about if it was a game like chess, where draws are more common, would it be okay for a team captain to send out a message to all team players as to remind them what the score in the match is and that it will only take one more draw to move on to the next round?

I know that some like BBW, play only for fun etc, and some would want to risk their play trying to win, even when a draw is all that was needed, but the true goal of a team tournament is for the team to do well, even at the expense of the individuals, so where do we draw the line on what is considered helping the team, and what is considered breaking the rules?

coan.net: I think you are probably right... I would like to hear from others on this....


when it comes to sports, I know it is acceptable for team members to take and give advice about strategy etc, but in a sport, you still have to make all the physical moves etc all on your own, its really only strategy that can be given.

I am thinking something like the Ryder cup in Golf for example. They can make strategies and give advice about a type of shot that should be attempted etc, but the individual player still has to possess the skill required, and it still comes down to how they perform
on an individual level that counts.

So I was thinking, at first, that it could be up to the team members who could help decide if it was a good time to offer a double, as long as none of them are getting their opinion from anything more than their own selves?

Or how about something as simple as pointing out that as a team we are in a position where a draw in your game will not help us at all, and that you should maybe play less conservatively or take more chances for a win than you might otherwise?

Puckish: I would not think it would be acceptable. Only after the move is made, then going back and asking "Did I do this correct, or would you have done something different" would be the most acceptable thing.

That way they are still playing their own game, plus learning how to play better the next time is a similar situation comes up.

Is giving or accepting advice in a team tournament acceptable?

I know that the help shouldnt come from some program or the like, but it seems to me, on first thought, that getting help from other team members should be okay?

Then I get to wondering.... couldnt that end up like playing against the best player from each team, if they were to be giving advice on moves and doubling etc?

But then again, who is to say that the advice from another player is always going to be good advice?

I think it is a team tournament, so let the team decide, the ultimate choice of what to do still always comes down to the person playing the game.

Vikings: That is interesting, because over at Goldtoken, they do add on extra points, although the basic rating points are lower (2 for a game).

tonyh: a match is a match, no matter how many games or points it takes to win it, so the answer is none

How many extra rating points do we get for winning a cubed match, rather than a straight, uncubed game?

Andersp: Yes, performance is a real problem here. May go to other sites where there i don't need to wait forever for the page to load

Puckish: Thanks for your kind words, but I don't want anybody to buy a membership for me. (I will quite possibly purchase a membership again when there is a decent autopass feature implemented, but for too long we gammon players have been regarded as second-class citizens on BrainKing, and until that changes, I have already provided enough financial support and encouragement.)

Puckish: me too

Profile: pgt (send message | show this user messages)

pgt (Phil) - [pgt, New Zealand, Brain Pawn, Male] Brain Pawn, 150 Brains (buy a membership for this user)
Total score: 2038 wins, 9 draws, 1853 losses, 19 won tournaments


Well, here is one casualty of the poor auto pass feature compromise that Fencer implemented

If we had more like him, enough to hurt the wallet a bit more, maybe something would be corrected?


Way to go Phil, and good luck to you!

wetware: Not rules, just rules of thumb, which in any case are no substitute for careful consideration of the position :-)

Puckish:  Yes, different rules apply when you're "racing" to avoid being gammoned, as opposed to racing with a hope of actually winning a game.

Hrqls: This thread has opened my eyes, thanks!

I always just assumed that getting yourself into position to bear off the fastest way possible was the way to go

But I had a recent example where I was ahead in the pip count in a race, and you would think that back to back double 4s could only help my cause. But since my 4 hole was empty, I didint get even one checker born off, and I ended up losing the game!


I will now consider other plays than simply piling my checkers in as fast as possible


I would assume, however, that if you are behind significantly in a game, it would be wise to get them in as soon a s possible, then hope for "good" rolls?

playBunny and Nabla: thanks!
from experience i already dont worry that much about a hole on 3 .. i dont like holes on 2 though .. but i now understand that a hole on 4 (or 5) is even worse :)

another nice example which was posted yesterday on dailygammon is the position discussed in this thread :
http://www.dailygammon.com/bg/forum2/main/read/22269#19

Hrqls: are there also positions in which its better to move only 1 piece into you home because it covers an empty spot (and leaving 1 outside your home)

Most definitely. It's more about the distribution than simply leaping over the bar. As nabla says, the 6-5-4 points are the most important. If you're stacked on 6 and 5 or 4 are empty then a roll that stacks the 6 higher is no good to you. You'll only waste rolls later unstacking it (unless you get 6-6). As you'll have no control over those later rolls but right now you have a known roll, why not place the checkers usefully.

Here's an example that I've just made up:
http://www.gellie.plus.com/DG_Extras/MakeBoard/ShowBoard.htm?MatchId=cIkmAAAAAAAA&PosnId=3HauAADc/CUBAA


With the 5-1 you could add two more men to the 6-point. Of the 20 moves shown in GnuBg, the 11/6 7/6 stacker is 17th and a Bad move (-0.48). It's much better to do 7/2 6/5. Putting one on a low point is greatly preferable to stacking. But the best move (it just edges it out) is 9/4 6/5. This builds on the 4-point, which is important because it's very weak in relation to the 6-point, and unstacks the 6-point a bit.

One additional point about the 4-point compared to the 3-point. If you roll a 3 and there's a hole on the 3-point then 6/3 will fill it. The next 3 will thus take a man off. If you have a hole on the 4-point and roll a 4 then you have to move a man deep from 6 or 5 and there's still a hole on the 4-point. The next 4 would thus waste another half a roll. The same applies to the 5-point but it's somewhat less troublesome. When the 6-point is cleared then a hole on the 5-point disappears automatically but a hole on the 4-point will still need the 5-point to be cleared before it disappears.

Hrqls: When bearing in it is best to aim for the points 4, 5 and 6. The low points can very well remain empty. The reason is that all dices below 4 will play fine even if the low points are empty (e.g. with a 3 you play 6/3, keeping a fine distribution). By contrast, an empty 4-point (for instance) is a nuisance, because all fours have to be played 6/2 or 5/1, accumulating checkers on the low points, that are likely to waste pips later.

So in your example, the move is definitely 8/6 8/4.

playBunny: thanks :)

although it seems like a waste of pips it might win me a move which is important

are there also positions in which its better to move only 1 piece into you home because it covers an empty spot (and leaving 1 outside your home) than moving 2 pieces into your home (and leaving that spot empty ?)

for example you all your pieces in your home except 2 .. those 2 are both on 8 while 2 is empty .. you 4+2 .. would you move 1 piece to 2 and leave the other at 8 .. or would you move 8/6 and 8/4 leaving 2 empty ?

Hrqls: I would definitely do 6/4/off.

If you do 6/1 2/off then a 2-1 on the next roll would leave an odd number of men and therefore be a wasted roll. That would be an unnecessary gift to your opponent.

If there had been one more man on the ace point (or one less) at the start of the 5-2 then it would make no difference which you did. The 2-1 would reduce your bearoff requirement by one roll whether one man came off or two.

Hrqls: With only 6 or so pieces left on the board, I personally would do what you did.

If I has many more pieces left, I would have probable tried to spread out my pieces.... nothing worse then getting double 4's and you can't even move 1 piece off because you have nothing on the "4" spot, but plenty left on the 5 or 6.

..... but then again, I'm far from a backgammon expert.

nabla: thanks ... i always move my pieces off as fast as possible (using as many pips as possible) .. but that doesnt seem to be the best way sometmimes

in this case it wont matter much though ;)

Hrqls: I think you are right, but that there is a difference only if you roll 2-1 or 1-1 with your next roll. If you roll 2-1, 6/4/off will likely win a roll in comparison to 6/1 5/2. If you roll 1-1, 6/4/off will likely lose a roll. Since 2-1 happens twice as often as 1-1 and you are way ahead (so after 1-1 you are very likely to win anyway), 6/4/off seems clearly better.
It is probable that if your opponent was ahead and you desperately needed doubles, 6/1 5/2 would be the correct move. I doubt there is much equity at stake in any case.

i rolled 5+2 in this position

what would be the best way to move ?

i moved 6 to 1 and 2 off

but i think it would have been better to move 6 to 4 and then 4 off .. that way i would have 1 piece off as well but i would have spread my remaining pieces more evenly (i would still have a piece on 2)

any opinions ?