Why do slot machine gamblers use stopping devices? Findings from a ‘Casino Lab’ experiment

ABSTRACT

Stopping devices are a structural characteristic of modern slot machines that enable the player to brake the spinning reels manually, but with no influence on the predetermined outcome. This study tested two mechanisms for why players might use a stopping device: (1) enhanced ‘illusory control’, and (2) faster game speed. Thirty student participants and 31 past-year slot machine gamblers played a multi-line slot machine equipped with a stop button, situated in a laboratory environment. During 20 minutes of play, participants could use the stop button as often as they wished. Contrary to predictions, the Gamblers’ Beliefs Questionnaire (GBQ), a trait measure of illusion of control, did not predict stop button usage. Participants who did and did not endorse the stop button as effective did not differ in their actual use of the device. Stop button use was associated with faster spin initiation latencies, and specifically increased following spins on which the use of the stop button coincided with a win. The data are interpreted as more consistent with a low-level operant conditioning account of slot machine gambling than a higher-level account based on cognitive distortions. By increasing speed of play, stopping devices may increase gambling losses and exaggerate gambling-related harms.

KEYWORDS:

• Electronic gaming machines
• illusions
• skill
• behaviour
• cognition

Acknowledgements

The authors would like to thank Angela Choi for her contributions in data collection, and the British Columbia Lottery Corporation (BCLC) for providing access to, and maintenance of, the slot machines for this experiment.

Notes

1. As there were 3 participants who did not use the stopping device at all, we compared the pace of play in those individuals (mean 10.5 spins per minute, or a spin every 5.7 s) against the pace of play in the 3 participants who recorded the highest number of stop presses (mean 16.6 spins per minute, or a spin every 3.6 s).