Slot Machine Algorithms
Random Number Generators and Slots Game Math
A slot machine algorithm is the computer program that operates modern slot machines. Mechanical slot machines, like your granddad might have played, didn’t really have an algorithm as we think of it. There were literally just some spinning reels that stopped randomly. Calculating the odds of winning on a mechanical slot machine was easy. Random number generators and algorithms have made it impossible for the average slot machine player to calculate the odds of winning.
Let’s look at an example. Suppose you have a mechanical slot machine with three reels and ten symbols on each reel. You win anytime all three reels have a symbol that matches up.
The odds of any given symbol coming up on a single reel is 1/10. To calculate the chances of that symbol coming up on three reels, you multiply that probably by the probability for the other two reels.
So your chances of winning with a particular symbol are 1/10 X 1/10 X 1/10, or 1/1000 (1 in 1000).
But you’re going to win if any of the symbols match. Since there are ten possibilities of that happening, you add the possibilities for each potential combination together. So 1/1000 + 1/1000 + 1/1000 + 1/1000 + 1/1000 + 1/1000 + 1/1000 + 1/1000 + 1/1000 + 1/1000 = 10/1000. You can reduce that just like any fraction to 1/100.
Which means you can expect to win something once out of every 100 spins.
Video Slot Machines
But modern slot machines don’t work that way. Since the reels aren’t real, they can hold a lot more than just 10 symbols. Some slot machines might have 25 symbols or more.
To make things even more exciting, the slot machine’s algorithm can be programmed so that a particular symbol comes up more or less often than the number of symbols would indicate. So you might have a symbol that comes up 1 in 50 times instead of 1 in 25, even though there are only 25 symbols on the virtual reel.
A slot machine player has no way of calculating the effect of the random number generator in this instance.
How This Affects the Payback Percentage
Going back to our mechanical slot machine example, suppose that when you win a jackpot, it pays out at 90 to 1. So if you’re betting a penny a pull, you’ve got a 1 in 100 chance of winning 90 coins. That means the casino keeps about 10% of all the money that’s plunked into the machine over the long run.
Using a slot machine algorithm and a random number generator program, slot machine manufacturers can create slot machines that hit small wins often but large wins very seldom.
They can also create machines which don’t hit often at all, but when they do hit, the jackpot is large.
The payback percentage can be anything the slot machine designer wants it to be. They just have to set the odds of winning and the payouts accordingly.
The payout percentage will always be less than the odds of winning. That’s how the casino makes its profit.
How This Affects Slot Machine Playing Strategy
That’s actually a bogus heading. There is NO strategy for playing most slot machines. The math is the math. No amount of strategic thinking can change the mathematical payback percentage of the slot machine.
Slots aren’t a skill game. You can use skill to make decisions in blackjack that will affect the mathematical expectation on each play. You can use skill to make decisions in video poker that will affect the mathematical expectation on each play.
But you cannot use skill to make decisions in slots that will affect the mathematical expectation of your play.
Does That Mean I Shouldn’t Play Slot Machines?
Since the chances of winning and/or losing at slot machines is algorithmically determined, does that mean I shouldn’t play?
Not necessarily.
Gambling is a form of entertainment. You can’t expect to win and still have fun. Not in the long run, anyway. But that doesn’t mean you can’t play and have fun.
You just need to remember one important tip. Don’t play with money you can’t afford to lose.
In the long run, we all break even eventually anyway. That’s philosophy. Think about it. But that doesn’t imply that we shouldn’t have a little fun and play while we’re here. Even if the slot machine algorithm is plotting against us.