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%.
Thad: I think the relevant quantities in context would be ten or more doubles and five or more boxcars. As far as your calcs go, I think the 10 doubles figure has to be multiplied by the combinations of 10 items chosen from 45, which I think is 45!/(10!*35!). A comparable adjustment needs to be made to the second calc, but I don't have time to work it out :-)
Gordon Shumway: OK, I didn't have the time yet to fix Nackgammon mat files as I was playing too much poker, but I fixed a small bug. So if you experience problems while converting mat files, try if it is fixed by the new version: MATFixer.
1. After you move your first piece to your opponents side, it is best to try to get it to the #5 or #6 spot on the board. At first, I tried to keep in the opponents starting block, but the rules say they they can not block all 6 of those spaces - so there will always be an opening there (so like an invisible piece). So moving your one piece to the #5 or #6 space will not allow your opponent to block anywhere on their starting side of the board.
2. At the same time, try to make a block of 6 spaces - like #5 - #10 on your side of the board. Of course now I try to block #5 & #6 as quickly as possible since I find those spaces to be the 2 most important when starting the game.
3. In a recent game, I ignored my (2) above and went strait to getting as many pieces to my opponents side - this has led me to almost putting a 6 space block on THEIR side of the board, possible blocking the rest of their starting pieces from advancing. If you are able to get some good rolls, if you can put 4-5 of your pieces over on your opponents side early - it can be very good for you.
OK, those are 3 of the strategies that I have started to use in the Fevga game. Any others have any tips?
playBunny: Thank you for the infos on Snowie .txt format! I think I'll integrate a Nackgammon fix on the weekend. About the pre tags: I hope they're now short enough. In Firefox 2 the scrollbar appears inside the post, so it didn't screw up the page for me...
Gordon Shumway: Might I suggest that you edit your post and split those long lines in the [pre] block? Now that we understand what they're about, they don't need to be correctly formatted. As they are they force the page to be scrollably too wide.
Gordon Shumway: It might be easy to integrate it, but it would be very bad style as it would mean that BrainKing first produces a broken mat code and then reads and manipulates it to remove the bugs, instead of not producing them in the first place. And I don't even think fixing the bugs right where they are would be any harder
Shshshsh ! This is what I was trying to subliminally suggest
A lot of numbers are the same in every line, so I guess that this is just the routine position setup. the last two digits are the dice rolled. But all that stuff in the beginning?
Yes, it is a routine position setup. I didn't know about the Snowie .txt format though, and thought that inserting the same string everytime would do it. The dice rolled shouldn't be of importance since they are given with the next move anyway. Having the good values in the first places is probably more important than I thought though.
Gordon Shumway: The segment within brackets is parsed as a Snowie .txt file. The following is taken from import.c of the GnuBg source code.
/* * Snowie .txt files * * The files are a single line with fields separated by * semicolons. Fields are numeric, except for player names. * * Field no meaning * 0 length of match (0 in money games) * 1 1 if Jacoby enabled, 0 in match play or disabled * 2 Don't know, all samples had 0. Maybe it's Nack gammon or * some other variant? * 3 Don't know. It was one in all money game samples, 0 in * match samples * 4 Player on roll 0 = 1st player * 5,6 Player names * 7 1 = Crawford game * 8,9 Scores for player 0, 1 * 10 Cube value * 11 Cube owner 1 = player on roll, 0 = centred, -1 opponent * 12 Chequers on bar for player on roll * 13..36 Points 1..24 from player on roll's point of view * 0 = empty, positive nos. for player on roll, negative * for opponent * 37 Chequers on bar for opponent * 38.39 Current roll (0,0 if not rolled) * */
nabla: Thank you so much, this gives me some motivation to play more backgammon on Brainking again !
Great to hear that this is so helpful!
As it is written in Java, it should be easy for Fencer to integrate it in his .mat generation code.
It might be easy to integrate it, but it would be very bad style as it would mean that BrainKing first produces a broken mat code and then reads and manipulates it to remove the bugs, instead of not producing them in the first place. And I don't even think fixing the bugs right where they are would be any harder
Errr... do you have any plans to fix the Nackgammon files as well ?
Not yet, as I don't really play Nackgammon (so far). I've just looked at a Nackgammon mat file from dailygammon.com at it looks kind of interesting though weird. The first move is always an "illegal play" which sets up the Nackgammon position and the first dice roll, the rest is exactly the same as for Backgammon. I just can't really make too much sense out of this "illegal play" string. Maybe you can? I'll attach a few examples.
All I can tell at first glance is that I would need to analyse the match and game data more seriously than I do now
5 point match
Game 1 Rich In Bunly Goodness : 0 natureseeker : 0 1) 12: Illegal play (5;0;1;0;0;natureseeker;Rich In Bunly Goodness;\ 0;0;0;1;0;0;-2;-2;0;0;0;4;0;3;0;0;0;-4;4;0;0;0;-3;0;-4;0;0;0;2;2;0;6;3;)\ 63: 24/18 23/20
[...]
Game 2 Rich In Bunly Goodness : 0 natureseeker : 1 1) 12: Illegal play (5;0;1;0;0;natureseeker;Rich In Bunly Goodness;\ 0;1;0;1;0;0;-2;-2;0;0;0;4;0;3;0;0;0;-4;4;0;0;0;-3;0;-4;0;0;0;2;2;0;6;4;) \ 64: 24/18 24/20
[...]
Game 3 Rich In Bunly Goodness : 0 natureseeker : 3 1) 12: Illegal play (5;0;1;0;0;natureseeker;Rich In Bunly Goodness;\ 0;3;0;1;0;0;-2;-2;0;0;0;4;0;3;0;0;0;-4;4;0;0;0;-3;0;-4;0;0;0;2;2;0;2;1;)\ 21: 23/21 21/20
[...]
Game 4 Rich In Bunly Goodness : 0 natureseeker : 4 1) 12: Illegal play \ (5;0;1;0;1;Rich In Bunly Goodness;natureseeker;\ 1;0;4;1;0;0;-2;-2;0;0;0;4;0;3;0;0;0;-4;4;0;0;0;-3;0;-4;0;0;0;2;2;0;6;1;) 2) 61: 13/7 8/7 11: 23/22 23/22 22/21 22/21
A lot of numbers are the same in every line, so I guess that this is just the routine position setup. the last two digits are the dice rolled. But all that stuff in the beginning?
Gordon Shumway: That is GREAT ! Your tool seems to work perfectly and is very easy to use. Especially helpful is the possibility to fix many files in one batch.
Thank you so much, this gives me some motivation to play more backgammon on Brainking again !
To those of you who want to import backgammon matches from BrainKing into external software and that don't want to wait for the bugs to be fixed: I didn't want to be patient too and so I wrote a small Java application as a temporary workaround. It fixes bugs 1181 and 1534 (But can't do anything about 1533) . In case someone wants to try it, here's a link: http://toedder.net/bk/matfixer.zip.
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?
Thad: The double probably threw the autopass out of whack. I wouldn't worry about it, just sit back and collect your winnings. Maybe he'll get what he deserves for that double, and you'll gammon him ;-)
I have a prime block in my home row and my opponent just doubled while on the bar. I accepted. Now it's his turn. Shouldn't autopass fire and make it my turn? Here's the game, although things might not be evident once he takes his turn: