What are the guidelines for cubing and taking cubes in str8 races? and does it vary according to the amount of pips left in the race?

For medium to long races, where both sides have somewhere between 60 and 120 pips, the simple guideline is this:

> Initial double if you are 8% ahead on the count.

> Redouble if you are 9% ahead.

> Take a double if you are no more than 12% behind.

So suppose you're in a straight race and your pip count is 100 and your opponent is 110. Since you're 10% ahead, you can double or redouble. But since your opponent is only 10% behind, he can also take.

As the race gets shorter, there are fewer rolls left in the game and just being on roll is a bigger edge. With a race where each side has less than 30 pips, you can often double when your pip count is equal to your opponent's.

8-9-12 Rule
A good rule for those just starting out is 8-9-12.

When your lead is 8%, you have an initial double, and at 9%, a recube. When your opponent trails by more than 12%, he must pass. Otherwise, he can take both an initial double and a recube.

The percentages are all applied to the pip count of the race leader.

Definition of Terms
L = pip count of race leader
T = pip count of trailer
D = difference = T - L

Minimum Initial Double
D = 8% of L

Minimum Redouble
D = 9% of L

Point of Last Take
D = 12% of L

In a race, which is generally considered a low-volatility circumstance, you don’t always have to double when you reach the minimum. The most efficient cubes occur just below the point of last take.

10% + 2 Rule
For a large variety of medium to long races, many experts use a modified form of 8-9-12, called 10% + 2. For this, add 10% to the pip count of the race leader, and then add 2 more pips. The result is the point of last take. Neil Kazaross adds 3 for races of about 90-95 pips or more.

Chris Bray Backgammon
Chris Bray has written an excellent monograph explaining race formulas. I highly recommend it. It’s only shortcoming is its omission of the Keith Count, a formula that many consider to be the best. In his Problem of the Day #19, Chris explains how to get a free copy of his monograph.

Backgammon Galore!
When you are ready for more complicated formulas, try reading some of these articles at Backgammon Galore! The three articles by Tom Keith, Walter Trice, and Douglas Zare are top-notch. Be forewarned. These are all for intermediate and advanced players.

Backgammon Galore! — Doubling in Races
http://www.bkgm.com/articles/page04.html#races

GNU Backgammon and eXtreme Backgammon
Both of these bots have racing formulas built in. In GnuBg, look under Analyze -> Race Theory. In XG, it's Analyze -> Race Formulas...

Hope this helps.

Mike

I forgot to mention to round up.

10% + 2 Rule
Add 10% to the pip count of the race leader, round up to the nearest whole number, and then add 2 more pips. The result is the point of last take. Neil Kazaross adds 3 for races of about 90-95 pips or more.

Mike

I see. . . Is there a way i can make these decisions by just looking at the difference in the pip counts for both sides? i'm not that good at math and i feel like calculating percentages during the game would take too long

could you give me an example to illustrate this concept?

or a better way to put it: is there a way to calculate percentages quickly in one's head? THe club where I play doesn't allow outside aids so they won't let me use paper and pen to get the percentages

Sure.

White - Pips 100

Black - Pips 89
Black on roll. Cube action?

DIAGRAM 1
XGID=---ABCDBBA----ab-c-dbba---:0:0:1:00:0:0:3:0:10

Finding 10% is easy. Just move the decimal point one place to the left.

In Diagram 1, Black is the race leader. His pip count is 89.

• 10% of 89 = 8.9
• Rounding up gives 9
• Adding 9 to 89 gives 98
• Adding 2 more pips gives 100.

100 is White’s point of last take. Since, in fact, White has a pip count of 100, Diagram 1 is a bare take for him.

White - Pips 101

Black - Pips 89
Black on roll. Cube action?

DIAGRAM 2
XGID=---ABCDBBA----abab-dbba---:0:0:1:00:0:0:3:0:10

Adding just 1 more pip for White, bumps his pip count to 101. As that exceeds his point of last take, he should pass.

XGR++ evals confirm both of these results.


White - Pips 101

Black - Pips 89
Black on roll. Cube action?

DIAGRAM 3
XGID=---ABCDBBA----ba-c-dbba---:0:0:1:00:0:0:3:0:10

In Diagram 3, White also has a pip count of 101. Once again, he should pass.

wow, this is awesome. thank you!

Question: when using the 10% + 2 guide, the guy getting doubled can take as long as the count of the guy who is doubling (after applying 10% +2) is the same or more than his own count?

my other question is: how do you use 10% + 2 when you are the one who wishes to double?

Sorry, I have one more questions about the 10% + 2 guide: Is it applicable to all noncontact medium to long races?

Right, but “point of last take” is a better way to phrase that. The guy getting doubled can take as long as his pip count does not exceed the point of last take found by 10% + 2.

This is where the work of Walter Trice comes in.

His excellent book Backgammon Bootcamp was criticized here recently, but I think unfairly. What disappoints some readers is that it is does not give broad coverage to all aspects of the game. Instead, it delves deeply into several areas where Trice did original research. Primary amongst those is race theory. Trice’s contributions in that area are unique.

It was Trice who first identified that, relative to the point of last take, the minimal doubling and redoubling points are nearly constant over a broad range of pip counts.

10% + 2 Rule
Add 10% to the pip count of the race leader, round up to the nearest whole number, and then add 2 more pips. The result is the trailer’s point of last take. Neil Kazaross recommends adding 3 for races of about 90-95 pips or more.

• The trailer can take as long as his pip count does not exceed his point of last take.
• From the point of last take, subtract 3 to find the pip count where the leader has a minimal initial double.
• Subtract 2 to find the pip count where the leader has a minimal redouble.

For almost all medium and long races, yes.

When a distibution is marred by excessive stacks and gaps, adjustments have to be made to the raw pip counts before applying 10% + 2. In the Bray monograph cited above, you will find the adjustments used by Jeff Ward in his Ward Formula. The article by Tom Keith gives the somewhat simpler adjustments of the Keith Count.

Adjustments are usually effective in medium-to-short races. They are mostly omitted in long races.

For very short races and pathological distributions, you have to fall back on the EPC (effective pip count) methods described in the Trice article cited above.

For last-turn scenarios, you have to count the rolls.

wow, thanks taper mike. This is exhaustive. I'm happy to have a study guide. I had no idea that even post contact play is so deep

Another question, if you don't mind: I've been practicing counting pips. I'm trying to learn to do it quickly, as I don't want to slow the game down too much and have the opp. wish to stop playing. My question is: how long would it take someone of average natural ability for arithmetic to learn how to count pips, apply 8-9-12 or 10% +2, identify point of initial first double, apply keith count, etc, and do all of it fairly quickly with a low margin of error? I don't think i'm dumb, but i'm no genius. I am, however, very obsessed with backgammon and I play every day, and study it almost everyday.

one last question: are there hub spots in the U.S. where a lot of cash game backgammon is played? Do you find soft games easily where you live?

I am probably the wrong person to ask. I don't count pips any better than average. One tip I can give is this. When you feel you are approaching a racing double, take the time to count the pips. From then on, keep a running count in your head, so you do not have to count them again. For example, if you roll 63, subtract that from the count in your head.

I am definitely the wrong person to ask. I find it hard to find any games at all without driving a substantial distance! Also, I am one of the new breed of players, more interested in the game than in gambling.

I wholeheartedly recommend first to follow an extensive course in book-keeping before attempting any cube decisions based on counting pips.

There are some essential skills for playing good backgammon, and counting pips is one of them. A good method is to play against XG or Snowie and turn off the pip count display. When you reach a position that requires a pip count, count the position and then check with the bot to see how far off you were. Do this every time you play. In a few months, you'll be surprised how fast and easy it is.

what's book keeping? (sorry, been playing less than a year)

also, I've watched some very good players at the local club. I've noticed that when bearing in and bearing off against contact, they can very quickly calculate how to leave themselves the fewest bad numbers possible for the next roll. I've noticed this is very critical when you're bearing in and trying to clear your 7, 8, and 9 points. But I have such a hard time with that. I mean, I can do it, but it takes me a while. So long, in fact, that I just try to do it by feel when I play against people because I don't want to slow the game way down. Will that change with practice?

I'm a person of average intelligence, and my math ability is, I think, just a hair above average. I love backgammon, but is this game to deep for me? Sometimes I feel like it's a game only high IQ types can master.

"Mastering" a game where the big issue is studying neural-net output is definitely a motivation test, not an intelligence test.

Also the intelligence tests can be trained, so at some extent those are a motivation test too. Apart from the raw intelligence, concentration and willpower are heavy weighing factors in our performance.
But surely, playing strategic games will improve our raw intelligence, though it is a concept that is diversified. Poker, chess and backgammon train aspects of our intelligence which will be overlapping for a great deal.

thank you slowkey and yogiman. You saying that just motivated me.

Wazzle, I feel sometimes that I am in the same place as you, but stick at it. I was reading a post about Moche, one of the best players saying that he only really started playing when he didn't pass his university entrance exam and he claimed that he is nothing special in maths. He puts his success down to study and hard work - interview link.

Some people have great ability in maths and they apply it to their backgammon, but I am sure that there are other attributes that are just as important that ordinary people like us can apply to our game. Counting pips is not difficult too do quickly enough if you use the half cross over method, try the North Michigan method.

I'm never going to be great a maths so I have focused on improving my strategy. The Problem of the week series has really helped me to improve. I urge you to study each of the solutions until you really understand them completely, not just the correct move, but the reason behind the moves.

Hopefully, you will soon be the person others will be looking out for.

Thank you for the links. i will def check them out.

What is the problem of the week series?

Bill Robertie has done a series of lessons posted to this website. You can see them by going into the Search menu and clicking Advanced Search. You need to fill out the form like this:
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awesome! thanks to all for schooling me