the dorbel daily

Sunday 18 April 2010

Tables

A reader asked me if I had a table of doubling and take points for various match scores. I haven't as it happens, but I did try to make one once. The trouble is that it needs to take into account whether the situation is dead cube or live cube or somewhere in between and be different for redoubles and take gammons into account. You end up with something very unwieldy, hard to memorise and hard to use. Old books were full of various tables. It is a good way to fill up pages that you haven't already filled with lots of diagrams! In my experience though, if you want a table telling you something, best to make it yourself. It's more likely to stay in your brain, you are more likely to understand it and you can tailor it to your own needs.
Having said all that, here is a useful table for you that I haven't seen anywhere else.
It is for the particular score 2-away, 1-away post-Crawford. For the trailer, the cube action is easy, turn the cube at the first legal opportunity. There is always a bright lad at the back of the class that points out that actually, there are certain rolls that make it correct for the trailer to play on and try for a gammon. This is probably true and if you are a world class analyst who can spot this opportunity and continue to evaluate it accurately as the game goes on, then go for it. You do gain a tiny bit of equity if you get it right. For the rest of us, just turn it!
For the leader, things aren't quite so simple. If you get the opening roll, then it isn't so bad. With most things you are a favourite in the game, so you can take. The exceptions are 4-1 and 2-1, where you are slightly below or slightly above 50% depending on who you believe. If you have correctly split the back men take or pass makes not much difference either way. When however your opponent has had the opening roll you get to reply before he can double and the question is, can you take or should you pass? You need to be 50% or preferably better to take so do you know all the answers? I bet you don't so here is my version of the truth. Print it out and keep it by you for reference. Refer to it AFTER you have made your decision in a match please, not before. Before is cheating.

The first column is what your opponent rolled, the second is what he played and the then we say what you need to do to get to 50%.
I use the word doublet for 6-6 etc to avoid confusion with the cube action. All plays are numbered from the viewpoint of the player on roll. Where it says "roll any doublet" you do have to make the best play with it as well, but you will usually be better than 50% even if you don't find the best play.

6-5..24/13. Roll any doublet.
6-4..24/14. Roll any doublet or hit on the 11pt.
6-4..24/18, 13/9. Roll any doublet, hit on the 16pt or make the 7pt.
6-3..24/18, 13/10. Roll any doublet, hit on the 15pt or make the 7pt.
6-3..24/15. Roll any doublet or hit on the 10pt.
6-2..24/18, 13/11. Roll any doublet, hit on the 14pt or make the 7pt.
6-1..13/7, 8/7. Roll 4-4, 3-3, 2-2 or 1-1.
5-4..24/20, 13/8. Roll any doublet, or make the 5pt.
5-3..8/3, 6/3. Roll any doublet (except 5-5) or make the 5pt.
5-2..13/8, 13/11. Roll any doublet, hit on the 14pt, make one of the 7, 5 or 4pts.
5-2..24/22, 13/8. Roll any doublet, make one of the 5, 4 or 3pts.
5-1..24/23, 13/8. Roll any doublet or 6-5, make one of the 7, 5, 4 or 2pts.
4-3..24/20, 24/21. Roll any doublet (except 5-5), make the 5pt or 4pt.
4-3..24/20, 13/10. Roll any doublet, hit on the 15pt or make the 5pt.
4-3..24/21, 13/9. Roll any doublet, hit on the 16pt, make the 5pt or 4pt.
4-3..13/9, 13/10. Roll any doublet (ex 5-5), hit in the outfield or make the 5pt.
4-2..8/4, 6/4. Roll any doublet (except 5-5)
4-1..24/20, 24/23. Roll any doublet (ex 5-5) or make the 5pt.
4-1..24/23, 13/9. Roll any doublet, hit on the 16pt, make the 5pt or the 2pt.
4-1..13/9, 6/5. Roll any doublet (ex 5-5) or hit a blot.
3-2..24/21, 13/11. Roll any doublet, hit on the 14pt, make the 5pt or 4pt.
3-2..13/10, 13/11. Roll any doublet (ex 5-5), hit in the outfield, make the 5 or 4pt.
3-1..8/5, 6/5. Roll 6-6, 3-3, 2-2, 1-1.
2-1..24/23, 13/11. Roll any doublet, hit on the 14pt, make the 5 or 4pt.
2-1..13/11, 6/5. Roll any doublet (ex 5-5) or hit a blot.
There you have it. Will it be any use? Practise with it. Set the board up, make an opening play and then roll the response. Note what you played, then do nine more before checking your answers. Nine out of ten is a pass mark!
Let me know how you get on.

Some interesting points. You will notice the weakness of 5-5 as a response in many cases, even though it is 20 pips. Note too that at dmp, splitting on the opening roll is preferable to slotting. Note the 24/20, 24/21 play for an opening 4-3. This is still a well-kept secret best play for this roll at this score, as is 24/20, 24/21 for 4-1. As well as being technically best, people who haven't met these before don't always know how to respond.
Some of the weakest reponses that still indicate a correct take are marginal and some of those just below the line are very close. let me know if you can see any that I have wrongly included or omitted. Thanks for reading and as it used to say in the Beano, more fun next week!

1 comment:

ah_clem said...

Nice post.