In bingo and casino games, we are reassured that games are fair by the knowledge that numbers, symbols or playing cards are selected at random. Games of online bingo, for example, must be played with a certified and independently tested Random Number Generator before any site can be granted a licence to trade in the United Kingdom.

But what does “random” mean? There are many definitions, dependent on the context, but when it comes to mathematics and statistics, the Oxford Dictionary states that random means “… governed by or involving equal chances for each item”. So for bingo (in the ninety ball game) that means that every number between one and ninety stands an equal chance of being the first ball drawn. In the next draw, each remaining number has a 1 in 89 chance of being drawn. And so on. For roulette, every number between 0 and 36 stands an equal chance of being the next winning number.

Sounds simple doesn’t it? But true randomness is a strange thing. The trouble is, humans have an inbuilt psychological tendency to look for patterns. This, according to scientists, would have been very useful when we were trying not to get eaten by sabre-toothed tigers thousands of years ago. It still is useful today: our brains can react much faster if our subconscious minds can match what our senses detect with information already stored in our memories. This is why we are “hard-wired” to detect patterns. The clearest example of this is our tendency to detect faces when they aren’t really there. Distant mountains on the Moon or Mars? Odd patterns in carpets or on wallpaper? Random dots on paper? We can see faces in them all.

What has this got to do with gaming? Well, we see patterns in numbers too, even when they truly are random. And this may lead us alter our strategy or tactics, or even to believe that things are fixed or corrupt in some way.

Let’s start with something very basic: the coin toss. Suppose we toss a real coin. Heads or Tails? We complete three sets of six coin tosses, and the following results occur: which of these patterns is truly random?

T T T T T T or H T H T H T or H T T H T H H

The answer is that all of them are. Each one of these combinations has a 1 in 64 chance of occurring. But the first two seem to us to form a pattern. Which call comes next? If we follow our natural instincts, we may think that in the first instance, maybe it is more likely to be Tails. Or maybe we think that because we have had six Tails in a row, the next coin toss must be Heads. In the second example, it looks like it may be Heads next. But the truth is, in all three cases, it is equally likely to be either. There is no REAL pattern; it just looks like it to us!

This can cause us to change our behaviour. In the National Lottery, many people choose numbers which are well spaced apart, and seem to us to be what we think of as random. 8, 15, 24, 31, 43 and 54 seem much more likely to win than 14, 15, 16, 17, 18 and 19. But it isn’t true. Each one of these combinations has an equal chance of being the six numbers drawn: about 1 in 45 million. I know that sounds unbelievable, but trust me, it’s true! The reason why it sounds so wrong is that sometimes, a “sequence” can occur randomly!

Our brains also just prefer things to be in order, and if a pattern isn’t found, we tend to create one. Look at what happens every time the National Lottery draw is made. The first thing the announcer does is to alter the sequence, because we prefer things to be in a pattern… “Here are tonight’s numbers in ascending order…”, so 39, 15, 54, 2, 53, 31 becomes 2, 15, 31, 39, 53, 54.

This effect can lead people to alter their decisions. Very often we think we see a pattern, and therefore believe that because of that, we are unlikely to win. For example, a bingo player may reject a card because there are too many numbers close together. Other times, we are fooled into seeing a pattern, and think that it must therefore end. A roulette player may assume the next number must be Even, because the wheel has just produced five Odd results in a row. The slot gamer believes the next spin must be a winner, because nothing has happened for ten games in a row. Well each and every one of these players may be right. Or they may be wrong. But there is no pattern. It’s all random!