title: The allure of multi-line games in modern slot machines.
abstract: OBJECTIVE
  In multi-line slot machines, players can wager on more than one line per spin. We sought to show that players preferred multi-line over single-line games, and that certain game features could cause multi-line game play to feel more rewarding.
  Reward was measured using post-reinforcement pauses (PRPs) following each outcome (the time between outcome delivery and the next spin). Gamblers (n = 102) played 250 spins on a 20-line game and 250 spins on a one-line game (answering questions about game experiences following each session). Playing one-line, a small credit gain (e.g. 2 cents) was a net win. In the 20-line game it was a net loss of 18 credits but was still accompanied by 'winning' sights and sounds.
  
  
  RESULTS
  Most players (94%) preferred the 20-line game. PRPs for small credit gains (net losses) in the 20-line game were equivalent, or larger than in the one-line game where such gains were wins. The largest increase in PRP size was between the 0 and 2 credit conditions for both games. Thus 20-line players reacted as though these net losses of 18 credits were rewarding. Players' estimates of the number of true wins were accurate in the one-line game, but they significantly over-estimated the number of true wins in the 20-line game (P < 0.01). Problem gamblers felt more skilful (P < 0.01) and were more absorbed (P < 0.01) by multi-line than single-line game play.
  
  
  CONCLUSIONS
  Multi-line games appear to be more appealing to gaming machine ('slots') players than single-line games. These games may be particularly absorbing for those with gambling problems.
authors: University of Waterloo, Waterloo, ON, Canada.
authors: Mike J
authors: MJ
authors: Dixon
authors: Candice
authors: C
authors: Graydon
authors: Kevin A
authors: KA
authors: Harrigan
authors: Lisa
authors: L
authors: Wojtowicz
authors: Vivian
authors: V
authors: Siu
authors: Jonathan A
authors: JA
authors: Fugelsang
mesh_terms: D016739:Behavior, Addictive / Q000523:psychology*; D005260:Female; D005715:Gambling / Q000523:psychology*; D000068957:Games, Recreational / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012054:Reinforcement, Psychology; D012201:Reward
keywords: Absorption; losses disguised as wins; post-reinforcement pauses; problem gambling; reinforcement; reward; slot machines