backgammon

When you watch a good player playing backgammon his game always seems to flow and he rarely seems to be stuck for a play. One reason for this is that good players always have a plan. Thus they only consider plays which help them to achieve their objectives.

Another reason for their apparent superiority is the more technical one of diversification. This is the opposite of duplication which we covered a few weeks ago. In duplication one seeks to give one's opponent fewer good rolls by leaving him the same number to achieve more than one thing, for example to hit a shot or cover a blot. With diversification one seeks to ensure that as many rolls of the dice as possible on one's next move will enable one to do something constructive.

A example is shown in the diagram position. Here Black has to play a "1". With White closed out on the bar, Black has the luxury of not having to worry about White's next roll; all he need concern himself with is optimising his chances for a gammon.

He could play 16/15, but this would leave him needing a 5 to hit the checker on the 18 point and also a 5 to hit the checker on the 10 point. With this play he will hit with 15 of the 36 possible rolls next turn. If instead he plays 6/5 then he will still need a 5 to hit the man on the 18 point but will need a 6 to hit on the 10 point. This play gives him 24 hitting rolls next turn - a 60 per cent increase. This is a simple application of the principle of diversification as normally one has to consider White's rolls as well, but the concept occurs frequently and is one that must be learnt and practised.

Consider the opening roll of 2-1. Suppose that Black plays 13/11, 6/5. If the slotted checker on the five point is hit, the checker on the 11 point is a hitter 6 pips away and six is the one number that Black cannot use to re-enter White's board. A simple but effective use of the principle of diversification.