Tagged: About a Tribute Live
This topic contains 6 replies, has 2 voices, and was last updated by Toon 5 years, 10 months ago.
May 2, 2012 at 21:24 #243
Both players have 2 checkers on their deuce point. What is the correct cube action when leading 2-away 3-away? The double is clear, but what about the take/pass decision? This situation arose between Patrick and Paul in the Brugge-Leuven 4 Cubes encounter. According to Michel, taking would be correct for money but a blunder at the match score. Why?May 4, 2012 at 14:21 #273
Toon Van Herreweghen
I know you try to entice me to comment this one…
If you take, this game is played for the match.
So you only take if your winning chance is at least 25% (= your match winning chance at 3-away, 1-away crawford)
You win when your opponent misses (10 rolls) and you bear off (26 rolls or around 3/4 of the time)
So out of 36 games, you win around 10 x 3/4 or 7.5 which is less than the 9 needed.
Start by classifying the situation based on the cube actions after you take and your opponent misses.
You have 26 winning rolls. You will redouble (26 > 18) and you opponent will take the 4-cube (26 < 27).
Realise that you will effectively quadruple the expected win compared to a cubeless game.
I like to express this expected win as R-18 = 26-18 = 8 points for 18 games.
So – in 18 games – you expect to win 4 x 8 = 32 points, 4 short of 36, thus 2 – 4/18 (or 2 – 1/5 for easiness)
Back to the original position. If you take:
You loose (-) 26 x 2
You win (+) 10 x (2 – 1/5) = 20 – 2 = 18
-52 + 18 = -34 which is slightly better than the -36 loss if you pass.
Take.May 6, 2012 at 11:37 #274
My apologies: in match play, if you take as the trailer this game is NOT played for the match.
Yes, you would redouble automatically, but no, the leader will not take the 4-cube.
(He needs something better than the 30% he would get after passing with the cube on 2, and he only gets your 10/36 missers)
Therefore, a miss by your opponent means a mere 2 points win for you, and leaves you still with only 70%.
The resulting decision is the same, though: you get 0% (26/36) or 70% (10/36)
Nearly 20% MWC by taking.
You are happy to grab the 25% by passing.May 7, 2012 at 13:30 #275
Toon’s analysis also shows that for money, the position (each player having 2 checkers on the deuce point) is indeed an initial double. But is it also a redouble? If the player on roll decides not to double, then in case he misses, he takes away his opponent’s powerful redouble.May 10, 2012 at 11:48 #279
I have to confess that I don’t torture my brain anymore with these calculations.
I’ll share a first-class approximation with you.
Situation: 2-roll bear off, money play, you ponder about doubling.
You roll out in Ra, you opponent in Rb (and let b = Rb-18).
And in the case: you know you will have to take a recube if you miss (18<Rb 2b
Redouble if Ra > 3b
I may get it slightly wrong in 5% of the marginal cases. But I won’t keep me from sleeping.May 10, 2012 at 12:06 #280
The previous text was garbled.
Case: 18 < Rb 2b
Reouble if: Ra > 3bMay 10, 2012 at 12:11 #281
there seems to be a problem with publishing texts including less-than and greater-than signs.
These are probably taken as delimiters of html elements.
Last time, in words:
Case: you will have to take a recube if you miss (Ra between 18 and 27)
Double if Ra is bigger than 2 times b
Redouble if Ra is bigger than 3 times b
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