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Abstract and Figures

Despite increasing research into how the structural characteristics of slot machines influence gambling behaviour there have been no experimental investigations into the effect of free-spins bonus features-a structural characteristic that is commonly central to the design of slot machines. This series of three experiments investigated the free-spins feature using slot machine simulations to determine whether participants allocate more wagers to a machine with free spins, and, which components of free-spins features drive this preference. In each experiment, participants were exposed to two computer-simulated slot machines-one with a free-spins feature or similar bonus feature and one without. Participants then completed a testing phase where they could freely switch between the two machines. In Experiment 1, participants did not prefer the machine with a simple free-spins feature. In Experiment 2 the free-spins feature incorporated additional elements such as sounds, animations, and an increased win frequency; participants preferred to gamble on this machine. The Experiment 3 "bonus feature" machine resembled the free spins machine in Experiment 2 except spins were not free; participants showed a clear preference for this machine also. These findings indicate that (1) free-spins features have a major influence over machine choice and (2) the "freeness" of the free-spins bonus features is not an important driver of preference, contrary to self-report and interview research with gamblers.
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ORIGINAL PAPER
Realistic Free-Spins Features Increase Preference
for Slot Machines
Lorance F. Taylor
1
Anne C. Macaskill
1
Maree J. Hunt
1
Published online: 20 July 2016
Springer Science+Business Media New York 2016
Abstract Despite increasing research into how the structural characteristics of slot
machines influence gambling behaviour there have been no experimental investigations
into the effect of free-spins bonus features—a structural characteristic that is commonly
central to the design of slot machines. This series of three experiments investigated the
free-spins feature using slot machine simulations to determine whether participants allo-
cate more wagers to a machine with free spins, and, which components of free-spins
features drive this preference. In each experiment, participants were exposed to two
computer-simulated slot machines—one with a free-spins feature or similar bonus feature
and one without. Participants then completed a testing phase where they could freely
switch between the two machines. In Experiment 1, participants did not prefer the machine
with a simple free-spins feature. In Experiment 2 the free-spins feature incorporated
additional elements such as sounds, animations, and an increased win frequency; partici-
pants preferred to gamble on this machine. The Experiment 3 ‘‘bonus feature’’ machine
resembled the free spins machine in Experiment 2 except spins were not free; participants
showed a clear preference for this machine also. These findings indicate that (1) free-spins
features have a major influence over machine choice and (2) the ‘‘freeness’’ of the free-
spins bonus features is not an important driver of preference, contrary to self-report and
interview research with gamblers.
Keywords Gambling Slot machines Free spins Bonus features EGMs
A portion of the data have been presented at the New Zealand Association for Behaviour Analysis annual
conferences (2014, 2015), and the Association for Behavior Analysis 8th international conference (2015).
These data will also form part of the first author’s PhD thesis.
&Lorance F. Taylor
lorance.taylor@vuw.ac.nz
1
School of Psychology, Victoria University of Wellington, PO Box 600, Wellington, New Zealand
123
J Gambl Stud (2017) 33:555–577
DOI 10.1007/s10899-016-9630-x
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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