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Beginners ... Look! Part One Backgammon Logo
19 March 2000
Aids (3)

Michael Crane

The inability to enter off the bar can often lead to losing the game and therefore it is advisable to know what rolls will enter and what wont. The next table shows this odds of re-entering with one man against n points closed.

Entering One Man Off The Bar
Closed points No. of Entering rolls
1 35
2 32
3 27
4 20
5 11

Quite obviously the more points closed the harder it is to re-enter . . . but not as hard as most beginners think! For example, often new players reckon that if 3 points are closed (50%) then only 18 rolls (50%) will re-enter; this is incorrect.

Take a look at the table showing 3 closed points - a total of 27 rolls re-enter, that's 75%, nowhere near the expected 50%. In fact with as many as 4 closed points you still re-enter with 20 rolls (55.55%). But, with two men on the bar these odds change dramatically. Look at the next table.

Entering Two Men Off The Bar

No. of Entering rolls
Closed points 2 men 1 man No men
1 25 35 1
2 16 32 4
3 9 27 9
4 4 20 16
5 1 11 25

Huge differences now; at the very best you have 25 re-entry rolls (69.44%) for both men with just one point closed, expand this to two points closed and it drops dramatically to just 16 re-entry rolls that's as little as 44.44%; and, if you are facing a home board with just a measly three points closed with two on the bar then all you have to re-enter with is 9 rolls (25%), which, if you reverse the math means you don't enter 75% of the time!

So, remember this table because it is well worth knowing just how bad/good it is to have two men on the bar with just a couple of points made.

I don't suggest you commit these entire tables to memory but if you can just remember half your game will improve. This is basic information that is essential to understanding the probabilities of dice rolls and their repercussions. In Part 2 I will explain why players lose games due to (what they think is) bad luck.

Beginners ... Look!  Part One
Introduction
Where Do We Start? - At The End! (1)
Where Do We Start? - At The End! (2)
Bearing off against opposition (1)
Bearing off against opposition (2)
Bearing in safely (1)
Bearing in safely (2)
The Opening Moves
Aids (1)
Aids (2)
Aids (3)


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