Slot Machine Persistence

A narrow opening, groove, or slit, such as a keyway in machinery or a slit for coins in a machine. Also, the space in a schedule or program where an activity can take place.

Despite a long-held image as arcade devices where little old ladies yank levers in high stakes bouts of chance, slot machines have come to dominate gambling revenue and profits. By one estimate, they account for 85 percent of industry profits in the United States alone. They’re a big business, and they’re here to stay.

In the early days of gambling, slots were all-or-nothing affairs: You yanked a lever and either all the cherries or lucky 7s lined up to give you some money or they didn’t. But advances in computer technology made it possible to build games that could be more mathematically precise. By the 2000s, they offered a wider range of payout percentages and allowed casinos to precisely control their games.

But that precision may not be the best thing for gamblers. A growing body of research suggests that near-miss feedback on slot machines can actually increase gambling persistence, perhaps because it reinforces learning processes—notably conditional reinforcement—that evolved to detect contingent rewards. One study manipulated the frequency of wins and near misses on a four-reel slot machine simulation, so that winning or losing was either 75% or 50% likely to occur. The researchers then put participants onto an extinction condition that removed both wins and near misses, but they found no difference in gambling persistence.