What are "stepper slots"?

5 June 2016

By John Grochowski

QUESTION: I’ve noticed that the big-paying symbols are off the line a lot more than they’re on the line. Is that intentional? Are the games programmed to tease players to thinking they’re close to a jackpot?

ANSWER: You must be playing three-reel stepper slots. I used to get this question fairly often when I first started writing about gaming in the 1990s, but rarely get it now that most play has shifted onto low-denomination video slots.

The near-miss appearance is a natural outgrowth of the odds of the game and the way slots with mechanical reels are programmed.

Mechanical reels have to be small enough to fit inside machine casings. So to generate enough possible reel combinations to yield the odds that make large payoffs possible, stepper slots are programmed with virtual reels. Virtual reels make the reels behave as if they have more symbols and spaces than they really do.

That’s done by assigning fewer random numbers to big-paying symbols than to others. Let’s say a programmer assigns one random number to a jackpot symbol. If he then assigns five numbers to the blank space just above and five more to the blank space just below the jackpot symbol, then the jackpot symbol will appear just above or just below the payline 10 times as often as it lands on the line.

Other blank spaces and low-paying symbols also are assigned more numbers than the jackpot symbol. That’s all done to create odds that will make combinations come up in the proper portions to yield a desired payback percentage and jackpot frequency.

A natural consequence of giving other symbols more random numbers is that the highest paying symbols will appear in the slot window but not on the payline a lot more often than they land on the payline. Programmers don’t have to build an intentional tease into the game. That all just happens because of the odds of the game.

Video slots are different. There are no physical reels that have to fit in machine casings, and reel strips can be as long as the game designer needs them to be. There’s no need to assign symbols surrounding a jackpot symbol extra random numbers, and so we don’t see the same near-miss effect on video slots we do on steppers.


QUESTION: I’m always fascinated by other players. The other day I was playing blackjack, and there were two players at the table. We all had kind of so-so cards. Nobody was losing big, but nobody was winning, either.

A fourth player came in, and suddenly things heated up. We started getting good hands, the dealer started busting, and everything was great. The new guy bought in for $200, played the last half of one six-deck shoe and maybe half of another one. He was doing great, and suddenly he said, “Ooops, have to go,” and he colored up more than $800. His last hand was a blackjack on a $50 bet.

If it was me, I wouldn’t be leaving when things were that hot. What would make him leave?

ANSWER: Maybe he had an appointment, had arranged to meet someone for lunch, had forgotten to do something important. There are any number of explanations, and I’ve been in many of those situations myself.

It’s also possible he was a card counter and after a run of good cards had seen the count turn negative. Maybe he knew there were more low cards than high cards remaining in the deck and was getting out while the getting was good.