Cube Handling

 Woolsey's law

 From: PersianLord Address: sharifazadeh@gmail.com Date: 12 March 2008 Subject: Woolsey's law Forum: BGonline

```We have an ongoing discussion in DailyGammon on Woolsey's law.  I claim
that we can ALWAYS apply Woolsey's law and that we can interpret
double/take situation with the help of it. Bert and Hardy claim otherwise
and say that this situation (double/take) is not included in Woolsey's law.

Who is right?
```

 Daniel Murphy  writes: ```Kit Woolsey, September 21, 1996 [http://www.bkgm.com/rgb/rgb.cgi?view+219]: For those of you who aren't familiar with my rule, it is as follows: If you aren't ABSOLUTELY sure whether the position is a take or a pass, then it is ALWAYS correct to double. I'm not kidding! I follow this rule religiously in actual play, and any player who does likewise will see his results improve tremendously. That's emphatic and clear. Note that it applies only to doubling decisions, not take decisions. Note that following this rule does not guarantee that your doubling decisions will always be right. Kit continues: Note that the converse is not necessarily true -- you may be absolutely sure it is a take and yet it is still correct to double, provided it is a very volatile position. --- The Woolsey rule isn't about what your opponent thinks he should do; it's all about what you think he should do. You have a cube decision. You ask yourself: Is it a pass or a take? You answer yourself: Not sure! What does that tell you? It tells you that subject to the limitation of your own ability to judge a position, the take/pass decision is close. So, either your opponent has a bare take, in which case you should double, because you can't be not good enough to double if you're opponent has only a bare take, and you can't be too good to double if your opponent has a take; not doubling has to be an error. Or, your opponent has a bare pass, in which case you should double, because you can't be to be too good to double if your opponent has only a marginal pass, and you can't be not good enough to double if your opponent should pass. I'll bet every aspiring player went through a phase where cube decisions were confused in this way: Maybe I'm not good enough to double ... wait, I think he should pass ... wait, maybe I'm too good! ... oh, but what if he takes? The Woolsey rule cuts through that crap. It says: focus on the take/pass decision. If you're not sure about the take/pass decision, double. Always. What can happen? Either (1) Your estimate isn't too bad. Then either (a) It's a close take. You're glad you doubled. You're especially glad if opponent passes. Either way, you gain. Or (b) It's a close pass. You're glad you doubled. You're especially glad if opponent takes. Either way, you gain. Or (2) Your estimate is off. Then either (a) It's too good to double. Alas, your double was a mistake. However, it could well be that your mistake was not large; after all, you thought opponent might have a take. And if you thought he might have a take, maybe he will take, probably a much greater error than your double. Or (b) It's not good enough to double. Again, your double was a mistake. But again, your mistake might not be large, since you thought opponent might have a pass. And again, if you thought he might pass, maybe he will! ```

 Matt Cohn-Geier  writes: ```I suppose I'll come out and state my opinion: Woolsey's Law doesn't always hold. Suppose you are up in a match, -2,-4. You have very good gammon chances. You're not sure whether the position is ND/T, ND/P, or maybe even D/T or D/P, but you figure there is a lesser chance of the last two. And you don't know whether your opponent will take or drop, since he's as clueless as you are, but it doesn't figure to be a gross blunder one way or the other. On the other hand, if you make a mistake and double when it's really ND/T, and your opponent takes, you've likely given up a lot more equity than he would have if he passed. I'm certainly not doubling. And that's just an example, the specifics may be changed. I'll also add a corollary, which I guess I might attribute to Robertie: Always do your best to determine what the correct cube action is for both sides before making a decision. ```

 Stick  writes: ```First thing you should do is read, or reread as the case may be, Woolsey's Doubling Rule: http://www.bkgm.com/articles/GOL/Aug02/rule.htm. I believe almost everything I'm going to mention has already been stated but I'd like to summarize more concisely with an example as to when and why Woolsey's rule should be employed. The biggest drawback I thought of when first reading about Kit's rule is that you're limited by your own playing strength. Just because I'm not sure whether it's a take or a pass doesn't mean Neil doesn't know for 100% certainty the D/ND T/P decision. I do think the rule is useful however for decent players and make use of it myself. I would only caution weaker players about using it because they could be chunking off large sums of equity sending over way early cubes (and then having to play out that position being the weaker player!) I think it's much more constructive to take the extra time to get under the T/P decision than to do as Kit says "Readers who have watched me play may notice that I often double a complicated position with apparently no thought. That's fine if you're Kit and you have enough bg experience under your belt to understand positions at a glance, but I wouldn't recommend it for Average Joe BG Player. Kit also lists 'the four possible cube strategies' for any position: 1. Not good enough to double, take 2. Double, Take 3. Double, Pass 4. Too good to double, pass Kit himself realizes his law isn't 100% foolproof in stating, "It is true that there are certain exceptions in match play when you are ahead in the match and the turn of the cube will put you out or nearly out, but in all other situations the law applies." In an example borrowed from Douglas Zare's article on Woolsey's Rule in Match Play [http://www.gammonvillage.com/news/article_display.cfm?resourceid=2425] we have the following position. Match to 3: X leads 1-0. X is on roll. 24 23 22 21 20 19 18 +---+---+---+---+---+---+---+---+---+---+---+---+---+ | O O O O | | O | | O O O O | | O | | | | | | | | | | | | | | | | | | X | | | | X X | | | | O X X X | | | | O X X X O X | | | | O X X X O X | | X | +---+---+---+---+---+---+---+---+---+---+---+---+---+ 1 2 3 4 5 6 7 Is it a take? Is it a pass? The problem is no matter what decision your opponent makes, right or wrong, you've made a blunder. You'd be much better off holding the cube whether or not your opponent takes or passes in this position thus making an exception to Woolsey's rule. We should resign ourselves to normal money-like match scores when using the Woolsey rule for the most part. It works exceptionally well for \$\$\$, no doubt about it. I personally would rather double a shade early, as I think Kit does, instead of waiting. Kit also states, and I'm not sure if he's the first to say it or not, though it has been etched in my brain for as long as I can remember, With correct cube play, I believe that at least 2/3's of initial doubles should be taken. For the record this is pretty accurate. I have many stats I've ripped from my GNU v. SW series and the fact that 2/3rds of the initial doubles should be taken holds water. So next time you're considering passing that initial double, make sure you know what you're doing! Stick ```

 Chuck Bower  writes: ```> I would only caution weaker players about using it because they could be > chunking off large sums of equity sending over way early cubes (and then > having to play out that position being the weaker player!) ....I wouldn't > recommend it for Average Joe BG Player. Well, isn't it possible that "Joe" is giving up just as much or even more equity by not doubling? You gotta learn sometime. I've always been impressed by the arguments good players try and give weak players. Quite often it goes something like "(I don't want to see a cube coming over in a gammonish position, so,) weaker player, the best thing for YOU to do is to leave it be." ```

Cube Handling

Against a weaker opponent  (Kit Woolsey, July 1994)
Closed board cube decisions  (Dan Pelton+, Jan 2009)
Cube concepts  (Peter Bell, Aug 1995)
Early game blitzes  (kruidenbuiltje, Jan 2011)
Early-late ratio  (Tom Keith, Sept 2003)
Endgame close out: Michael's 432 rule  (Michael Bo Hansen+, Feb 1998)
Endgame close out: Spleischft formula  (Simon Larsen, Sept 1999)
Endgame closeout: win percentages  (David Rubin+, Oct 2010)
Evaluating the position  (Daniel Murphy, Feb 2001)
Evaluating the position  (Daniel Murphy, Mar 2000)
How does rake affect cube actions?  (Paul Epstein+, Sept 2005)
How to use the doubling cube  (Michael J. Zehr, Nov 1993)
Liveliness of the cube  (Kit Woolsey, Apr 1997)
PRAT--Position, Race, and Threats  (Alan Webb, Feb 2001)
Playing your opponent  (Morris Pearl+, Jan 2002)
References  (Chuck Bower, Nov 1997)
Robertie's rule  (Chuck Bower, Sept 2006)
Rough guidelines  (Michael J. Zehr, Dec 1993)
The take/pass decision  (Otis+, Aug 2007)
Too good to double  (Michael J. Zehr, May 1997)
Too good to double--Janowski's formula  (Chuck Bower, Jan 1997)
Value of an ace-point game  (Raccoon+, June 2006)
Value of an ace-point game  (Øystein Johansen, Aug 2000)
Volatility  (Chuck Bower, Oct 1998)
Volatility  (Kit Woolsey, Sept 1996)
When to accept a double  (Daniel Murphy+, Feb 2001)
When to beaver  (Walter Trice, Aug 1999)
When to double  (Kit Woolsey, Nov 1994)
With the Jacoby rule  (KL Gerber+, Nov 2002)
With the Jacoby rule  (Gary Wong, Dec 1997)
Woolsey's law  (PersianLord+, Mar 2008)
Woolsey's law  (Kit Woolsey, Sept 1996)
Words of wisdom  (Chris C., Dec 2003)