We all become accustomed to what “normal” bridge hands are like. Few of us regularly play where computer dealing is the norm, as the equipment is expensive, and not many bridge clubs can afford it. When we do get a chance to play computer dealt hands, we often find the hands a bit odd – for example, more voids and long suits than usual, and when we are playing a contract, the adverse trumps seem to split more unfavourably than we might expect . A typical conclusion is that the computer isn’t providing properly random hands, and we are suspicious of it. Why might this be? Is there a problem with computers not being able to generate truly random deals? Actually, no.
When a hand of bridge is played, there is an obvious tendency for cards to be played in sets of 4 of the same suit – a non-random pattern. When the hand is finished, we gather our 13 cards up and put them back in the board, ready for the next table. What we should of course always do is to give them a bit of a shuffle first, so that the next player doesn’t receive clues about what order the cards were played in. But when it’s the last hand of the evening, what’s the point? Do we just put them back in the board as they are, because they are going to be shuffled and re-dealt next time?
At the start of a new session, when we all sit down and are presented with a few boards to shuffle and deal, what do we do? Do we just pull out the 4 hands, stack them into a deck of 52, give them a quick shuffle, and deal? If so, we only partially reduce the non-random pattern of the cards. It is rather hard to properly mix a deck to fully randomise – it takes several expert riffle shuffles, and few of us have the skill to do it, even if we had the time. But we’re usually in a bit of a hurry to get on with things, and don’t want to spend ages and ages shuffling.
The result is that we get a disproportionate number of flattish hands. Over time, that becomes the “norm” – what we expect to see, and judge to be typical.
Why should it matter? After all, we’re playing duplicate, so the hands are the same for everyone.
There are at least two very good reasons why it does matter. Firstly, we are playing for the fun of it, and most of us would agree that it’s a lot more enjoyable when there is competitive bidding, plenty of game and slam calls (especially based on shape rather than just a huge point count), and not so many evenings when you get a large number of rather dull hands. Secondly, it keeps us sharper and improves our skills, as thoughtful play of the cards, and overcalling, get rewarded more often.
The good news is the choice isn’t between investing in an expensive shiny new computer dealing system, or putting up with things as they are. There is a third option, that the maths experts tell us is remarkably effective. And it’s really very simple. The answer is to give your 13 cards a good shuffle before you put them back in the board, after the last hand of the evening. This breaks up the sequence of the cards, so that when they are dealt next time, even with imperfect shuffling, the probability is that the new deal will be much more random.
If we can get into the habit of doing that, then our bridge stands to become more fun, and better for everyone.