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Old 06-10-2021, 10:46 AM   #1
a_free_lunch
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Question about holding doubles

In a 2016 article, Robertie writes that "In almost all normal 5-point holding games like the ones shown here, White [the player doing the holding] has a pretty easy take." This is meant to be true even if the doubler has a pretty large lead, since this improves the taking player's timing. For example, in a Position 3 (see the linked article), Black leads by 30 pips and yet White has a take.

After reading this, I was quite surprised to see that the following position is a big drop: https://imageshack.com/i/pmwuPwGej (unfortunately, I couldn't insert the image into the thread). As can be seen, taking is a 0.132 error. This strikes me as very surprising since the position seems quite similar to Robertie's Position 3.

So what is the key difference between these two positions?
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Old 06-10-2021, 11:33 AM   #2
_Z_
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Re: Question about holding doubles

I might have taken this, but I think what's happening is that the combination of the timing and the big race lead is causing an unusually ideal situation for Black. Usually when you have a big race lead against a holding game, it means your timing is bad, since you don't have a lot of rolls before needing to clear the midpoint. But the fact that Black doesn't have any low points in his board made means all those checkers are available to play from his mid, 8 and 6 points, so he has lots of time to roll a clearing double.

Also, I don't think it's actually too good. What's happening there, is that XG takes too much in holding games, so during the "no double" portion of the rollout, it's getting some bad takes which inflates the no double equity.
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Old 06-10-2021, 11:47 AM   #3
_Z_
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Re: Question about holding doubles

If you look at the position I posted here:

https://forumserver.twoplustwo.com/s...7&postcount=13

It's sort of similar in the sense that it's stronger than it looks because there's an unusually good timing situation.

(Note that the player with the holding game is on roll.)
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Old 06-10-2021, 01:32 PM   #4
Robertie
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Re: Question about holding doubles

Z nailed it. This is a very unusual combination of a huge race lead combined with tons of timing. The player coming home has plenty of time to roll a double so the holder doesn't get as many shots as he needs to compensate for his huge race deficit.
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Old 06-10-2021, 01:40 PM   #5
RolldUpTrips
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Re: Question about holding doubles

Yikes I would have taken this in a flash and not appreciated the nuance. Cool position.
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Old 06-11-2021, 06:21 AM   #6
a_free_lunch
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Re: Question about holding doubles

Brilliant, thanks for the explanation!
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