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Backgammon => Fibsboard Forum Matches => FFM1 => Topic started by: blitzxz on April 15, 2009, 05:33:28 AM

Poll
Question: Cube?
Option 1: Double votes: 1
Option 2: No double votes: 9
Title: Match 1, Game 1, Move 8, Forum Double
Post by: blitzxz on April 15, 2009, 05:33:28 AM
Cube?

Score: 0-0/5
Pips: Black 135 White 127
GnuID: TN/AAwITt8EYIA:cAmgAAAAAAAA
Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: dropper on April 15, 2009, 08:36:03 AM
Spoiler
No double (beaver). What's the match length? I don't suppose this is a money match with the Jacoby rule?
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Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: diane on April 15, 2009, 10:26:37 AM
Quote from: dropper on April 15, 2009, 08:36:03 AM
Spoiler
No double (beaver). What's the match length? I don't suppose this is a money match with the Jacoby rule?
[close]

It is a 5 pt match, that info is now added in, along with a pip count etc
Spoiler
I still want to cube this - he looks to be in a pickle to me.
[close]
Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: lewscannon on April 15, 2009, 02:40:23 PM
Quote from: diane on April 15, 2009, 10:26:37 AM
It is a 5 pt match, that info is now added in, along with a pip count etc
Spoiler
I still want to cube this - he looks to be in a pickle to me.
[close]


Spoiler
You're getting close to a cube, but I wouldn't pull the trigger quite yet
[close]

Diane, you're supposed to wait for me before you post.
Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: Zorba on April 15, 2009, 03:54:43 PM
Spoiler

If we double, would factotum have a take? If there's any doubt in your mind about his take, you should double (the famous Woolsey Rule).

In this case, the take seems crystal clear. We didn't hit yet and there's plenty of rolls that miss. We're a little behind in the race. Even after a hit by us, we're still far from winning this one.

If the take is clear, it can still be a good double if there are enough lucky sequences (our roll+move followed by factotum's roll+move) where we lose our market, that is, factotum would have to pass if we double. Those lucky sequences are the ones after which we would regret not having doubled now.

If we get a lucky sequence, but factotum can still take next time, we lose nothing by holding the cube for now. We simply double next time. If we get a (very) unlucky sequence, we are of course happy that we haven't doubled.

So how does it look here? There seem to be market-losing sequences. If we roll 4-4 and factotum dances, he should pass then. 3-3 and dance, ditto. Maybe some other hit/cover and dance sequences? This is not enough to warrant a double now. Only a few of our rolls are good enough, and even after those, we still need a dance by factotum to make them decisive. After all sorts of other rolls and responses by factotum, we can either double next turn, or we are happy that we didn't double.

Another good rule of thumb for the doubling decision, is to give ourselves a good roll (but not the best) and then give opponent a poor roll (but not his worst). Would opponent still have a take after this? Then it's probably not a double.

Here, a good roll (but not our best) might be 4-5, 24/20* 8/3 hit and cover. Then a bad roll for fact (but not his worst) might be 4-2, enter but no return-hit or anchor.
It seems quite clear that factotum would still have a take after such a scenario, so then it's not a double now.

In other words: Our position here is not yet threatening enough to double. It's only threatening to threaten. No double now, but it might well be a (strong) double next turn if things go well.

Or even simpler: Hit first, then double.
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Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: diane on April 15, 2009, 04:48:57 PM
Quote from: lewscannon on April 15, 2009, 02:40:23 PM
Spoiler
You're getting close to a cube, but I wouldn't pull the trigger quite yet
[close]

Diane, you're supposed to wait for me before you post.

Darn, that's why I got it wrong again....

Spoiler
It is the threatening to threaten part that I like about this - I think it would scare most folk and be an easy win :-) Course, factotum isn't most folk  :laugh:, but I still think if anything good happens, it will be a drop, and ideally I want this taken
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Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: socksey on April 15, 2009, 07:18:31 PM
I'm sticking with my first instinct and no double, even tho I want to double.   :laugh:

socksey



"An eye for an eye makes the whole world blind." - Mahatma Gandhi
Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: blitzxz on April 17, 2009, 08:33:40 AM
Quote from: dropper on April 15, 2009, 08:36:03 AM
No double (beaver). What's the match length? I don't suppose this is a money match with the Jacoby rule?

"Score: 0-0/5"
Title: Re: Match 1, Game 1, Move 8, Forum Double
Post by: Zorba on April 17, 2009, 10:53:06 PM
Cube analysis
2-ply cubeless equity  +0,0881 (Money:  +0,0915)
   51,84  19,65   0,44 -  48,16  14,12   0,50
Cubeful equities:
1. No double            +0,1311
2. Double, pass         +1,0000  ( +0,8689)
3. Double, take         -0,1321  ( -0,2632)
Proper cube action: No double, take (23,2%)

Cube analysis
3-ply cubeless equity  +0,1257 (Money:  +0,1299)
   53,02  20,24   0,42 -  46,98  13,28   0,42
Cubeful equities:
1. No double            +0,1688
2. Double, pass         +1,0000  ( +0,8312)
3. Double, take         -0,0509  ( -0,2197)
Proper cube action: No double, take (20,9%)