Predictors of Return Rate Discrimination in Slot Machine Play

The purpose of this study was to investigate the extent to which accurate estimates of payback percentages and volatility combined with prior learning, enabled players to successfully discriminate between multi-line/multi-credit slot machines that provided differing rates of reinforcement. The aim was to determine if the capacity to discriminate structural characteristics of gaming machines influenced player choices in selecting ‘favourite’ slot machines. Slot machine gambling history, gambling beliefs and knowledge, impulsivity, illusions of control, and problem solving style were assessed in a sample of 48 first year undergraduate psychology students. Participants were subsequently exposed to a choice paradigm where they could freely select to play either of two concurrently presented PC-simulated slot machines programmed to randomly differ in expected player return rates (payback percentage) and win frequency (volatility). Results suggest that prior learning and cognitions (particularly gambler’s fallacy) but not payback, were major contributors to the ability of a player to discriminate volatility between slot machines. Participants displayed a general tendency to discriminate payback, but counter-intuitively placed more bets on the slot machine with lower payback percentage rates.     

An Analysis of Switching and Non-switching Slot Machine Player Behaviour

Learning theory predicts that, given the repeated choice to bet between two concurrently available slot machines, gamblers will learn to bet more money on the machine with higher expected return (payback percentage) or higher win probability per spin (volatility). The purpose of this study was to investigate whether this occurs when the two machines vary orthogonally on payback percentage and volatility. The sample comprised 52 first year psychology students (mean age = 20.3 years, 20 females, 32 males) who had played a gaming machine at least once in the previous 12 months. Participants were administered a battery of questionnaires designed to assess level of knowledge on the characteristics and operation of poker machines, frequency of poker machine play in the past 12 months, personality traits of impulsivity and capacity for cognitive reflection, and gambling beliefs. For the experimental task, participants were instructed to play on two PC-simulated electronic gaming machines (EGMs or slot machines) that differed on payback percentage and volatility, with the option of freely switching between EGMs after a practice phase. Results indicated that participants were able to easily discriminate between machines and manifested a preference to play machines offering higher payback or volatility. These findings diverged from previous findings of no preference for play on higher payback/volatility machines, potentially due to of the current study’s absence of the option to make multi-line and multi-credit bets. It was concluded that return rate parameters like payback percentage and volatility strongly influenced slot machine preference in the absence of betting options like multi-line bets, though more research is needed to determine the effects of such betting options on player distribution of money between multiple EGMs.     

Modern Multi-line Slot Machine Games: The Effect of Lines Wagered on Winners,Losers, Bonuses,and Losses Disguised as Wins

We simulated the commercially available multi-line slot machine game “Money Storm,” including its bonus wins. Our results show that after a specified amount of time (such as 1 or 50 h), when players played a single line, there were marked differences between one player and the next—a few won a lot, others lost far more than average. When playing 20 lines there were fewer big winners and fewer players quickly losing a large percentage of their money. We simulated a Gambler’s Ruin scenario whereby players arrived with $100 and made $1 wagers until broke. Again we saw a reduction in the variability among player as the number of lines wagered increased, fewer players lost their entire bankroll quickly, and fewer players had big wins. The bonus wins in Money Storm contribute approximately 24 % to the payback of the game, and our simulations of bonus wins shows that with 20 lines wagered the players spend approximately 11 % of their time in bonus wins. With one line wagered, there are no losses disguised as wins while with 20 lines wagered the majority of hits are losses disguised as wins. Players using multi-line machines can thus tune the characteristics of the machine gambling experience to match their preferred pattern, though most seem in practice to bet on the most possible lines. Our results serve to inform researchers, counsellors, gamblers and others about how slot machines are designed, and the effect that wagering on multiple lines has on short-term and long-term play, bonus wins, and losses disguised as wins.     

Gamblers can discriminate ‘tight’ from ‘loose’ electronic gambling machines

All slot machines make money over time, but the payouts to the players can differ. ‘Loose’ machines pay out more than ‘tight’ machines. Gamblers (n = 1402) at Ontario slots venues were assessed using the Problem Gambling Severity Index. Their beliefs about slots were polled using the Informational Biases Scale. Problem gamblers were more likely than non-problem and at-risk gamblers to endorse the belief that ‘some slot machines keep me from winning because they are programmed to produce fewer wins than normal’. We then showed that after extensive play (60 hours), 9 out of 10 gamblers were able to correctly discriminate a ‘loose’ machine (98% payback) from a ‘tight’ machine (85% payback). Problem gamblers' assertions that there are ‘loose’ and ‘tight’ machines demonstrate a belief rooted in reality. The ability to distinguish ‘loose’ from ‘tight’ machines may be interpreted as a skill by players. Such skill, when overestimated, may lead to erroneous cognitions.     

The Impact of Sound in Modern Multiline Video Slot Machine Play

Slot machine wins and losses have distinctive, measurable, physiological effects on players. The contributing factors to these effects remain under-explored. We believe that sound is one of these key contributing factors. Sound plays an important role in reinforcement, and thus on arousal level and stress response of players. It is the use of sound for positive reinforcement in particular that we believe influences the player. In the current study, we investigate the role that sound plays in psychophysical responses to slot machine play. A total of 96 gamblers played a slot machine simulator with and without sound being paired with reinforcement. Skin conductance responses and heart rate, as well as subjective judgments about the gambling experience were examined. The results showed that the sound influenced the arousal of participants both psychophysically and psychologically. The sound also influenced players’ preferences, with the majority of players preferring to play slot machines that were accompanied by winning sounds. The sounds also caused players to significantly overestimate the number of times they won while playing the slot machine.     

Misinterpreting ‘winning’ in multiline slot machine games

On multiline slot machines, ‘wins’ often amount to less than the spin wager, resulting in a monetary loss to the gambler. Nevertheless, these losses disguised as wins (LDWs) are accompanied by potentially reinforcing audiovisual feedback. A concern for gambling behaviour is whether or not players categorize LDWs as wins or losses, as miscategorization could effectively increase the reinforcement rate of these games. The purpose of this study was to evaluate whether novice gamblers psychologically miscategorize LDWs. Forty-seven novices (undergraduate students) played 200 spins on an actual slot machine with credits, then estimated how often they won. It was found that the more LDWs players were exposed to, the higher their win estimates. In a subsequent ‘think out loud’ playing session, the majority of novices also verbally miscategorized LDWs as wins. We conclude that LDWs could increase the reinforcement rate of these games, despite not increasing the payout to the gambler.     

Realistic Free-Spins Features Increase Preference for Slot Machines

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.     

Event frequency,excitement and desire to gamble,among pathological gamblers

In this study we compared gambling behaviour of 15 pathological gamblers (PG) and 15 non-problem gamblers (NPG) on two conditions of a commercially available slot machine. One condition used a commercially available two-second event frequency (games per minute), while the other condition used an experimental three-second event frequency. The payback percentage (wins relative to losses) and reward frequency (wins over number of games played) varied randomly across conditions. The results showed that PG had significantly higher measures than NPG on time spent gambling, excitement level and desire to play again in the two-second condition. In the three-second condition there were no differences in excitement level and desire to play again. The number of PG playing the maximum time (60 minutes) was reduced in the three-second version, and reward frequency contributed to reduction in time spent gambling. The results may have implications for understanding behavioural mechanisms of pathological gambling among slot machine players.     

An Experiment on the Social Facilitation of Gambling Behavior

Research and theory regarding the social facilitation effect generates the expectation that the presence of other gamblers (or co-actors) in a gaming venue is likely to intensify individual gambling behavior and magnify losses. Fifty male and 66 female participants (116 total) played a computer-simulated electronic gaming machine with a fixed winning sequence, followed by an indefinite losing sequence. Measures of the intensity of gambling behavior included the final payout (a direct measure of losses), average bet-size, number of trials played, and the speed of play. Some participants received false feedback from the computer designed to suggest that other gamers in adjacent rooms were playing and sometimes winning at the same game. Persons who received both sight and sound information, including winning bells and instant messages regarding the wins of other (fake) players, placed more bets and lost more money compared to the other conditions with less information.     

Structural Changes to Electronic Gaming Machines as Effective Harm Minimization Strategies for Non-Problem and Problem Gamblers

This study aimed to evaluate the effectiveness of three proposed modifications to the structural characteristics of electronic gaming machines as harm minimisation strategies for non-problem and probable problem gamblers. Structural changes included reducing the maximum bet size, reducing reel spin and removing large note acceptors. Behavioural patterns of play were observed in 779 participants attending clubs and hotels. Observations were conducted in the gaming venue during regular gaming sessions. Eight experimental machines were designed to represent every combination of the modifications. 210 participants played at least one modified and one unmodified machine. Following play, the South Oaks Gambling Screen (SOGS) was administered. More problem than non-problem gamblers used high denomination bill acceptors and bet over one-dollar per wager. Machines modified to accept the one-dollar maximum bet were played for less time and were associated with smaller losses, fewer individual wagers and lower levels of alcohol consumption and smoking. It was concluded that the reduction of maximum bet levels was the only modification likely to be effective as a harm minimization strategy for problem gamblers.     

The Frustrating Effects of Just Missing the Jackpot: Slot Machine Near-Misses Trigger Large Skin Conductance Responses, But No Post-reinforcement Pauses

Near-misses in slot machines resemble jackpot wins but fall just short. Previous research has demonstrated that near-misses are behaviorally reinforcing despite the absence of monetary reward. We assessed the hedonic properties of near-misses by measuring the time between outcome delivery and the initiation of the next spin—the post-reinforcement pause (PRP) and skin conductance responses (SCRs) for losses, near-misses, and a range of wins (5, 15, 25, 50 or 250 credits) while participants (N = 122) played a slot machine simulator. PRPs and SCRs were compared for 40 low frequency and 22 high frequency slots players who were non-problem gamblers, 37 at risk players, and 23 problem gamblers. For winning outcomes, PRPs and SCRs tracked monotonically with win size such that progressively larger wins were associated with progressively larger PRPs and SCRs. Near-misses with jackpot symbols landing on the first two reels had significantly larger SCRs than regular losses, and other types of near misses. Crucially, PRPs for this kind of near-miss were significantly smaller than all wins, and when non-parametric statistics were used, significantly smaller than regular losses. This pattern of large SCRs and small PRPs suggest that these are highly frustrating outcomes that stimulate appetitive components of the reward system to promote continued gambling.     

Evaluating the Effectiveness of a Limited Reduction in Electronic Gaming Machine Availability on Perceived Gambling Behaviour and Objective Expenditure

In Australia, there is evidence to suggest that there is a positive association between the geographical accessibility of electronic gaming machines (EGMs) and the frequency and intensity of gambling in local areas. Evidence such as this has been used to introduce regulatory policies to reduce the geographical accessibility of EGMs through the reduction of gaming machine numbers in venues. The aim of this paper was to describe the process involved in the 15 per cent reduction in gaming machine numbers in the state of South Australia and the apparent effects on gaming revenue and gambling behaviours. Detailed analysis of objective EGM data as well as survey-based interviews with 400 regular EGM players provided only limited evidence of behavioural changes or significant reductions in gaming revenue. The paper describes the nature of industry responses to circumvent the effects of the reduction in machine numbers and the implications of these findings for future regulatory policies relating to EGM gambling.     

Blue Gum Gaming Machine: An Evaluation of Responsible Gambling Features

Structural characteristics of gaming machines contribute to persistence in play and excessive losses. The purpose of this study was to evaluate the effectiveness of five proposed responsible gaming features: responsible gaming messages; a bank meter quarantining winnings until termination of play; alarm clock facilitating setting time-reminders; demo mode allowing play without money; and a charity donation feature where residual amounts can be donated rather than played to zero credits. A series of ten modified gaming machines were located in five Australian gambling venues. The sample comprised 300 patrons attending the venue and who played the gaming machines. Participants completed a structured interview eliciting gambling and socio-demographic data and information on their perceptions and experience of play on the index machines. Results showed that one-quarter of participants considered that these features would contribute to preventing recreational gamblers from developing problems. Just under half of the participants rated these effects to be at least moderate or significant. The promising results suggest that further refinements to several of these features could represent a modest but effective approach to minimising excessive gambling on gaming machines.     

Impulsivity and Gambling Type Among Treatment-Seeking Disordered Gamblers: An Explorative Study

Several studies have found that certain traits of impulsivity are associated with gambling disorder, and influence its severity. Furthermore, it has been suggested that some forms of gambling, particularly electronic gambling machines, are particularly widespread among pathological gamblers. In the present, exploratory study, we aim to clarify the role played by impulsivity in influencing the choice of specific gambling activities, by examining the relation between individual dimensions of impulsivity, and the choice of specific gambling activities in a clinical population. 100 consecutively admitted pathological gamblers at the National Problem Gambling Clinic in London (UK) in 2014 were administered the UPPS-P and BIS-11 impulsivity questionnaires, the Problem Gambling Severity Index, and underwent a structured interview concerning their gambling activities in the month and year prior to assessment. The correlation between individual gambling activities and impulsivity dimensions was analyzed both at a bivariate level, and using logistic regression. We found a significant correlation between Negative Urgency, Motor impulsivity and low-stakes machine gambling on multivariate analysis. Negative urgency (i.e. the tendency to act impulsively in response to negative affect), and Motor impulsivity (a tendency to rash action and restlessness) might be mediating factors in the choice of electronic gambling machines, particularly among patients whose gambling is escape-oriented. Structural and situational characteristics of gambling machines, particularly the widespread availability of low-stakes—rather than high-stakes—gaming machines, might concur to the choice of this form of gambling among individuals who present higher negative urgency and restlessness.     

An empirical study of sex differences in gaming machine play among club members

Abstract

This paper helps address a deficiency of gender specific research into gambling. Using predominantly non‐parametric tests, the paper analyses data from 1,257 female and 1,743 male respondents in a telephone survey of 3,000 members selected randomly from six large Sydney clubs. The results support female gambling stereotypes of lower individual bets and lower overall expenditure, but not of lower participation and frequency of play, and shorter duration of gambling sessions. Further, regular female gaming machine players appear more likely than non‐regular female players to be migrants, either young or old, and from lower socio‐economic groups. Regular female gaming machine players also appear to forgo the social side of playing machines, to spend more overall and to be more at risk of problem gambling than non‐regular female players. Finally, the distinguishing socio‐demographic characteristics and machine playing behaviours of regular male gaming machine players are very similar to those for regular female gaming machine players.     

Implicit Valuation of the Near-Miss is Dependent on Outcome Context

Gambling studies have described a “near-miss effect” wherein the experience of almost winning increases gambling persistence. The near-miss has been proposed to inflate the value of preceding actions through its perceptual similarity to wins. We demonstrate here, however, that it acts as a conditioned stimulus to positively or negatively influence valuation, dependent on reward expectation and cognitive engagement. When subjects are asked to choose between two simulated slot machines, near-misses increase valuation of machines with a low payout rate, whereas they decrease valuation of high payout machines. This contextual effect impairs decisions and persists regardless of manipulations to outcome feedback or financial incentive provided for good performance. It is consistent with proposals that near-misses cause frustration when wins are expected, and we propose that it increases choice stochasticity and overrides avoidance of low-valued options. Intriguingly, the near-miss effect disappears when subjects are required to explicitly value machines by placing bets, rather than choosing between them. We propose that this task increases cognitive engagement and recruits participation of brain regions involved in cognitive processing, causing inhibition of otherwise dominant systems of decision-making. Our results reveal that only implicit, rather than explicit strategies of decision-making are affected by near-misses, and that the brain can fluidly shift between these strategies according to task demands.     

Profiling Lady Luck: An Empirical Study of Gambling and Problem Gambling Amongst Female Club Members

This paper helps to address a deficiency of gender-specific research into gambling. It focuses on gambling participation, gaming machine play, and problem gambling amongst 1,257 female respondents to a telephone survey of 3,000 members selected randomly from the membership lists of six of the largest clubs in Sydney, Australia. Using predominantly non-parametric tests, results identify a range of behaviors that characterize the gambling activities of female club members when compared to their male counterparts. Testing four hypotheses revealed that, when compared to male club members, the females had a higher preference for bingo, lotto, lotteries, pools, and gaming machines; they gambled less frequently on off-course and on-course betting, casino table games and hotel gaming machines, but more frequently on bingo; they were more likely to display patterns of gaming machine play that maximize playing time; and they experienced problem gambling at levels comparable to males. Further research questions arising from the study's findings are discussed.     

The Influence of Gaming Expenditure on Crime Rates in South Australia: A Local Area Empirical Investigation

Although there has been much speculation about the possible links between gambling and crime rates, relevant quantitative evidence has been practically non-existent in Australia to date. This paper reports the results of research that utilised a model designed to investigate the potential relationship between electronic gaming machine expenditures and property (income-generating) crime rates reported to police in local areas in South Australia in 2002–2003. The research found that the higher the expenditures on gaming machines in a particular local area per adult, the higher the income-generating crime rate in that area. No such relationship was found between gaming machine expenditure and non-income-generating crime rates. However, further research is required before any policy-relevant conclusions can be drawn.     

An Initial Investigation of Individual Rate-of-Play Preferences and Associations with EGM Gambling Behavior

Electronic gambling machines (EGMs) show a strong association with gambling problems. The high speed of gaming offered by modern EGMs allows playing numerous games in a short span of time, which is thought to contribute to attentional distraction, increased spending and prolonged play. However, the relationship between EGM speeds and potentially risk-related gambling behavior remains unclear. We introduce a novel approach to investigating the role of gaming speed in EGM gambling behavior by examining ‘individual rate-of-play’ (I-ROP) during simulated EGM gambling. A community sample of male regular gamblers (N = 72) played virtual slot machines in pairs offering sequentially adjusted game speeds towards the estimation of a behaviorally expressed preference speed, or I-ROP. This initial experiment aimed to explore the variability of I-ROPs during simulated EGM gambling, and examine behavior while playing EGMs at speeds relative to their I-ROP. Estimated I-ROPs ranged from less than one half second to over seven seconds and were negatively associated with cognitive ability, but not related to problem gambling severity, impulsiveness, or gambling-related cognitions. Subsequent gambling sessions on EGMs offering individually calibrated faster and slower gaming speeds were associated with greater and reduced risk-related gambling behaviors respectively. I-ROPs represent a potentially informative construct for exploring influences of gaming speed on gambling behavior, and may lend insight into potential risk-related behavior an individual vulnerability with respect to commercially available EGMs that warrants additional research.     

A profile of gaming machine players in clubs in Sydney,Australia

New South Wales, Australia, is one of the major markets in the world for machine gaming, with its 1,441 registered clubs holding the dominant share of the state's machines. This study examined machine gambling behavior amongst a random sample of 3,000 club members from six of the largest clubs in Sydney, the capital city of New South Wales. The findings identify their machine gambling preferences and participation levels, isolate significant sociodemographic and other differences between gaming machine and non-gaming machine players, measure the prevalence of probable pathological gambling associated with machine gambling, and identify certain characteristics which differ significantly between probable pathological and non-pathological machine gamblers amongst the respondents.