Upping the Reinforcement Rate by Playing the Maximum Lines in Multi-line Slot Machine Play

Reinforcement is a key component of slot machine play. Multi-line video slot-machine play can lead to "losses disguised as wins" (LDWs) which are credit gains that total less than the wager on the spin. LDWs only occur on multi-line games, with their frequency increasing with the number of lines played. If perceived as wins, they will be reinforcing to the player despite actually being losses. It has been suggested that players may attempt to maximize their reinforcement rates by playing maximum lines with a minimum bet per line. We recorded the actual game play of 83 participants on two different machines having different LDW rates. On both machines, players, regardless of problem gambling status, seldom bet on a single line (<6% of spins), preferring to bet on the maximum number of lines available (>70% of spins). Post-reinforcement pauses indicated that players found LDWs significantly more rewarding than losses and as rewarding as small wins. Players significantly overestimated the number of times they won more than their spin wager (i.e., miscategorizing LDWs as wins). Players indicated a number of game traits that made them prefer one machine over the other. Players who preferred the game with many LDWs endorsed "lack of long losing streaks" and "frequency of wins" to a greater degree than those preferring the other game. In sum, gamblers prefer playing maximum lines. Maximum line-play increases the frequency of LDWs. Players may miscategorize LDWs as wins, thus increasing the perceived reinforcement rate of multi-line slot machine.