Addictive Gameplay: What Casual Game Designers Can
Learn from Slot Machine Research
Kevin A. Harrigan
Canadian Centre of Arts and
University of Waterloo
+001 519 888 4567
Canadian Centre of Arts and
University of Waterloo
+001 519 888 4567
Michael J. Dixon
Department of Psychology
University of Waterloo
Slot machines are by far the most popular form of casino
gambling today. Slot machine research, however, is a neglected
area of exploration for video game designers and academics. This
paper discusses structural characteristics that slot machine games
and casual games have in common and then presents ideas that
designers of casual games might learn from existing research into
the design of contemporary digital slot machines. In particular, we
introduce ideas about how casual games designers might
capitalize on the properties of slot machines that encourage repeat
Categories and Subject Descriptors
K.8.0 [Computing Milieux]: Computing Milieux-Personal
Design, Human Factors
Computer Games, Slot machines, Design, Addictive, Popularity,
Slot machine research is a neglected area of exploration for video
game designers and academics. This paper asks what designers of
casual games might learn from existing research into the design of
contemporary digital slot machines (also known as video slots,
video fruit machines, or electronic gambling machines) and its
effect on players. We propose here that existing research into the
design of slot machine games may provide casual game designers
with insights into what makes a game popular and, in particular,
how casual games designers might capitalize on the properties of
slot machines that encourage repeat play. In particular we focus
on the structural characteristics of games, by which we mean
‘those features inherent within the video game itself that may
facilitate initiation, development and maintenance of video game
playing over time’ . Although all video games may share some
of these design principles and can benefit from an understanding
of these principles, our focus is on casual games, which are
defined by the International Game Developers’ Association as
‘games that generally involve less complicated game controls and
overall complexity in terms of gameplay or investment required to
get through a game’ .
Throughout this paper, we have chosen to use the casual game
Tetris for most of our examples, due to its enduring popularity.
Originally developed in 1984 by Alexey Pajitnov, Tetris remains
one of the most popular and highest grossing casual games of all
time. Lifetime unit sales totals are estimated at over 100 million
for just the mobile platform, and Tetris is currently available on
over 800 different handset models . The game frequently
makes Top 10 Games of All Time lists . The goal of Tetris is to
place differently-shaped falling blocks together like a puzzle.
When blocks in one row are all filled, the row is deleted from the
puzzle. Points are scored by clearing rows as well as with each
block placed. The game is over when the player has misplaced
enough blocks that they fill up the space without having cleared
We begin with an overview of the similarities between slot
machines and casual games, and then focus on research into slot
machines and video games structural characteristics to outline
some key design principles that can be adopted by designers of
2. EXISTING SIMILARITIES BETWEEN
SLOT MACHINES AND CASUAL GAMES
Like casual games, slot machine games do not have complex
gameplay and the player/gambler does not need to invest much
time to understand the game controls. Figure 1 is a photo of a
modern slot machine game. The game controls, seen at the bottom
of Figure 1, are simple buttons for selecting the number of lines to
be wagered upon and the credits wagered per line. Most wins
must be three or more symbols starting from the left on a played
line. The player simply presses ‘spin’ and the slot machine
displays animated spinning reels for 5-6 seconds and then tallies
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the result. Even if the gambler were to misinterpret the outcome,
it does not really matter, in that the slot machine always adds or
subtracts credits appropriately. In Figure 1, the player has
wagered 75 credits by wagering 5 credits on each of 15 lines. The
player won 25 credits by having three clams on one of the 15
zigzag lines. One credit is a nickel, and thus the 75-credit wager is
Figure 1. Slot Machine screen showing play.
The demographics of casual game and slot machine players are
quite similar. According to various surveys, slots players are
approximately 60% males and 40% females, with the average age
being approximately 39-45 years old (see for example , a
survey of over 3,000 individuals). The demographics of slot
machine players are similar to the results reported by the 2007
Casual Game report, which showed that casual game players are
fairly evenly split with 48.3% male and 51.7% female (although
females account for 73% of paying casual gamers) and most
casual game players (62%) are over 35 years old .
Casual games represent one of the fastest growing areas of video
game sales. With distribution through Internet, mobile and smart
phones, social networks such as Facebook, as well as downloads
through consoles such as through Xbox LIVE Arcade, casual
games now account for more than $3 billion in annual sales. To
compare that figure, however, slot machines represent
approximately $1 billion in sales each day in the United States
alone (a figure that denotes profits by casinos, rather than take-
home purchases) . Over the past few decades, slot machines
have become more popular and profitable for casinos than table
games. Approximately 60% of slot machine revenue is derived
from moderate and severe problem gamblers . The enormous
popularity of slot machines continues to grow as they are
increasingly found outside of designated casinos in jurisdictions
where they were previously restricted by government regulations.
Casual games represent perhaps the easiest entry to the games
marketplace for designers, and due to their generally lower cost
and shorter development cycles are the more common
development choice for students and start-ups. These factors also
make casual games useful teaching tools for educators. On the
other hand, although slot machine games have simple gameplay,
the gambling industry is highly regulated and thus entry to the
market of slot machine games is very limited as the process of
having a game approved is onerous. For that reason, the slot
machine marketplace is dominated by only a few manufacturers,
and each manufacturer creates both the game and the physical
Slot machine game design today is becoming increasingly similar
to that of video games. In part, this is due to the influence of game
designers from the video game industry into slot machine
companies. For instance, Joe Kaminkow once designed games for
Data East Pinball as well as Sega, before going on to be Vice
President for Game Design at International Game Technology
(IGT), the leading slot manufacturer, bringing many ideas from
the game industry with him. It is also common for video game
sound designers and composers to work on contract for slot
Unlike the old mechanical reel slots, today’s slot machines
incorporate high-resolution graphics, cinematic cut-scene
sequences, high quality audio, and bonus levels. They are also
increasing in complexity, although slot machines are attractive to
players because, like casual games, they:
• require little or no training or previous experience;
• require little time commitment although players can continue
to play for hours;
• are quick and easy to play – slots are considered a continuous
form of gambling as you spin every 5-6 seconds;
• offer instant rewards for play in terms of feedback (whether
financial, through points, or audio and video rewards).
In fact, Wood et al  argue that ‘The only major difference
[between slots and video games] is that most video games do not
offer the chance to win money by playing.’ Another major
difference is that skill has little or no influence on the result of a
slot machine spin whereas in casual games skill is important.
Fisher and Griffiths  outline a series of characteristics that
video games and slot machines share including:
• the provision of auditory and visual rewards for winning
• incremental rewards that reinforce ‘correct’ behavior;
• opportunities for peer approval;
• attention or recognition through competition.
As each industry advances, the importance of refining these
characteristics has become more of a science than an art. Despite
media attention, however, there has been very little academic
research into video game addiction, with some researchers
questioning the validity of the concept . However, there is
little doubt as to the addictive nature of slot machines, which has
clear social and financial consequences, and as such, considerable
research has been conducted into the addictive or popular
properties of slot machines.
Below we present and discuss design principles from slot machine
game design. For each of our principles, we outline existing slot
machine research and compare the use of the design feature in slot
machines with Tetris. By understanding the science behind these
principles, we may begin to incorporate or enhance these areas in
casual game design.
3. SLOT MACHINE DESIGN PRINCIPLES
In slot machines, the most obvious form of reward is a financial
pay-off. The player bets an amount of money, and the player wins
back more than they bet. The actual payout from wins on slot
machines and their relationship to rewards is far more
complicated, however (see below). In addition to the financial
rewards, however, are the other rewards that the player receives.
Auditory and visual rewards are commonly heard and seen when a
player wins. These include verbal reinforcement from virtual
characters that may speak to the player , as well as ‘rolling
sounds’ and various sound effects, as well as cut-scene animations
and flashing lights.
The importance of sound effects in particular as reward is so
apparent that slot machine manufacturers now use sampled sound
effects of coins entering the hopper even when no coins are used
on the machines. Describes Bill Hecht, an audio engineer for IGT,
‘We basically mixed several recordings of quarters falling on a
metal tray and then fattened up the sound with the sound of falling
dollars’ . Moreover, these false coin sounds can portray wins
much larger than the actual win. Research into sound’s effects on
video games has found that sound can contribute significantly to
stress and/or arousal during game play. One study even found that
realistic sound was the most important feature of a video game
. But regular sounds can quickly fade into the background of a
casino’s environmental noise. As such, randomized sound effects
are now increasingly in use, in order to increase the perception
that the sound is more real than it is in actuality, and to reduce the
recognition that it is merely careful programming at play .
On slot machines almost all auditory rewards are accompanied by
a visual reward system—flashing lights, and/or some form of cut-
scene animation, which typically take place after a large win.
Similarly, in video games, cut-scenes are also commonly used in
casual games as a reward when a player achieves a certain score
or clears a particularly difficult level. An animation is played and
the player gets a moment’s rest. On the original Game Boy
version of Tetris (1987), for instance, after clearing level 9 on the
high difficulty setting, a series of Russian dancers and performers
play, followed by a space shuttle launching. In most other
versions of Tetris, it is common to have Russian Cossack dancers
in cut-scenes after achieving a certain level or score.
Auditory and visual rewards are common in casual games,
although underused, and in the case of sound, often being given a
back seat and small budget. We feel that sound in casual games is
particularly overlooked, and could be one significant yet simple
avenue for making games more attractive. To use Tetris as an
example of this auditory rewards idea at work, pleasing sound
effects are played upon clearing a row, as well as achieving
certain scores. What a modern Tetris could benefit from is the
idea of variable sound effects. For instance, the sound for clearing
a row could vary based on the level, the colours of blocks in the
row, or any other number of parameters. Similarly, one area that is
lacking in casual game design is the use of replay sequences as
cut-scenes. For instance, the game could track events that
rewarded the player with a high amount of points, or a particularly
difficult action sequence. These sequences could be played back
in cut-scenes, in much the same way that replays are used in some
sports games, such as NHL 2010 (EA Sports 2009). An announcer
could even comment on the play, combining auditory and visual
In addition to these auditory and visual rewards, there are also
rewards of a social nature. Casinos provide a unique form of
positive reinforcement called ‘hand pays.’ Casinos have a cutoff
amount for jackpot wins which must be paid to the gambler in
cash by hand by a casino attendant. When a player wins the cutoff
amount or more, the machine enters a ‘hold mode’ and the
machine’s lights flash and sirens sound. At this time, players often
receive peer praise from their fellow gamblers. After a minute or
two, an attendant arrives and pays the gambler the winning
amount in cash. The machine then returns to normal play.
While casual games typically may be played on one’s own,
increasingly, winners are playing on portable handheld devices,
and/or sharing games over the Internet, in a sense obtaining peer
praise through competition or sharing. Moreover, the use of leader
boards serves to reinforce behaviour through peer praise (see
below). To use Tetris as an example again, in addition to auditory
and visual rewards discussed, some rewards come in the form of
points and leveling up. After a certain score or playing time is
achieved, the player’s level is increased. The goal—the reward—
is achieving a high level. This higher level, however, is
accompanied by an increase in difficulty. The skill involved,
therefore, in achieving a higher level, must also increase with that
achievement. High scores may be shared with others through
leader boards or verbally (‘I just got to level 22!’) for peer praise.
3.2 Reinforcement Schedules
Of course, the behaviours that are rewarded or punished in a game
are only part of the equation: The timing of these events is of
critical importance. Slot machines are designed to provide regular
and frequent small wins. King, Delfabbro and Griffiths, drawing
on the work of B.F Skinner, argue that in fact the reinforcement
schedule is more important than the rewards themselves . Slot
machines incorporate a random ratio reinforcement schedule,
which means that both the amount of the reward (i.e. the number
of credits won) and the number of spins between rewards are
varied . A random ratio is well known to be a powerful
reward schedule as it makes it difficult for individuals to cease a
The frequency of positive reinforcement (small wins) affects
machine choice in slot machine play , with a preference for
regular small wins, although the overall average percentage
payback or return rate is also important . With modern slot
machine games, players often win ‘something’ on one-third of
their spins, on average. This high frequency also helps to disguise
loss . Immediacy of some form of reward is also important:
players play more games when rewarded immediately than with a
delayed response . It is the combination of a high frequency
of rewards, the results of the bet, and the immediacy of the
rewards that contribute to a game’s addictiveness, argues Griffiths
In video games, experience points, level-ups, and item rewards are
all part of the reinforcement schedule. However, as some
researchers have found, ‘some elements of failure and punishment
in video games are perhaps essential in order to establish the
contextual worth of in-game rewards (i.e., that rewards can
prevent the player from losing) and show the player that making
progress is not simply inevitable but skill-based.’ Moreover, a
game must provide enough frustration as to be interesting. If the
game is too easy, the player will lose interest. According to
Csikszentmihalyi’s concept of flow, games must become
progressively more difficult in order to maintain our interest. 
3.3 Non-Rewards: Near Misses
The algorithm the slot machine game designers use is simple yet
eloquent. The reels on the slot machine are weighted so that the
blank symbols that are adjacent to jackpot symbols each occur on
the payline six times more often than the jackpots symbols appear
on the payline. The third reel in Figure 2 is an example. The blank
below the ‘Blazing 7’ appears on the payline six times out of
every 256 spins, on average. The ‘Blazing 7’ that is shown just
above the payline appears on the payline once, on average, in
every 256 spins. The blank above the ‘Blazing 7’ on the third reel
(not shown) appears on the payline six times out of 256 spins, on
average. Thus, on average, in every 256 spins the jackpot symbol
appears above and below the payline 12 times more often than it
appears on the payline.
Figure 2. A ‘near miss’ of 7s failing to line up
The casino industry uses near misses to increase the entertainment
value of the games, and regulators allow the intentional
programming of near misses by the manufacturers. The fact that
near misses increase the entertainment value of the games has
been proven by problem gambling researchers who have shown
that near misses increase the number of games played . If you
walk around a casino floor you will see that players rarely react to
the frequently occurring small wins but they often be seen
reacting to near misses with comments such as ‘aw shucks’
coupled with physical reactions such as snapping their fingers.
The ratio of 12:1 of near misses being designed into the games
versus near misses that happening by chance alone has been
arrived at by slot machine game designers over many years and
this can be used as a guideline for casual game designers – if there
were too many near misses then players would grow accustomed
to the near misses and thus the near misses would not increase the
entertainment value of the game. The 12:1 ratio seems to be the
‘sweet spot’ regarding how many near misses will make the game
With near misses, argues King et al , the players are not
constantly losing, but constantly ‘nearly winning’. Near misses
have not, to our knowledge, been intentionally included in any
casual game design, although there it may be argued that the
nature of video games encourages the feeling of ‘almost
happening’. In Tetris, for example, players may accidentally place
a block in the wrong spot (a fairly common occurrence depending
on the controls involved and the experience of the player). As the
speed of the blocks increases, errors are made not in the intended
placement of the block, but in the actual placement. In this sense,
the player believes that it was an error of physical dexterity that
can be fixed and that trying again will solve the problem.
3.4 Non-Rewards: Losses Disguised as Wins
A slot machine loss disguised as a win (LDW) is a play in which
the player ‘wins’ but receives a payout amount of money less than
that of the amount wagered, hence actually losing on the wager
. So for example, a gambler might wager $2 on a play and win
back 50 cents. The gambler is actually losing $1.50, but is given
the reinforcement cues (the auditory and visual rewards) of a win.
Physiologically, gamblers respond as if they are winning when
they are, in actuality, not winning at all .
These losses disguised as wins are the consequence of allowing
players to wager on multiple lines on one spin. For example, a
player may wager 25 cents on each of 15 lines for a total wager of
$3.75. That player may win $1 on one line and 75 cents on
another line for a total ‘win’ of $1.75. The player will experience
the winning graphics and winning sounds although they have just
lost $2.00 in a six-second spin. On modern slot machines, the
number of LDWs is often more than the number of regular wins.
Ontario’s casinos have a wide mixture of slot machines including
older style one-line slot machines that have no LDWs and modern
50-line games with a LDW on every fifth spin or so. We visit one
casino frequently and the multi-line games are much busier than
the single line games. In fact, in many jurisdictions the modern
multi-line games have completely replaced the older-style single
line games. On hundreds of casino visits we observed the playing
habits of gamblers playing multi-line games, and the
overwhelming majority are playing a small amount, such as five
cents on 15 or more lines per spin (i.e. a $0.75 wager) and are
experiencing LDWs on approximately 20% of their spins.
The research is clear that players physiologically experience
LDWs and regular wins identically . Thus, even while taking
money from the gambler, the slot machine game designers have
figured out how to reward the player. This technique may be
particularly appropriate for casual games. Casual gamers are not
as ‘hard core’ as other gamers and may be looking for a game that
provides rewards without too much time and effort on their part.
Finding a place in the causal game to reinforce the gambler with
‘wins’ (through rewards of a score, auditory nature, etc.) that are
not really wins may provide just the arousal needed to increase the
time on that game by the casual gamer.
This loss disguised as a win phenomenon is not found in Tetris,
although it is certainly found in other games to a limited and
unscientific extent. The original Prince of Persia platform game
(1989 Brøderbund) for instance would often make the player work
hard to get to a potion. It was only when the potion was drunk that
the player would discover that it was a bad potion that subtracted
from their health score. Had the player been given the auditory
rewards of a win in this case (a good potion sound), it may have
been enough to trick the player into physiologically believing it
was a positive event, even though their life score was being
reduced. There is no research, however, into this phenomenon in
video games, although gambling research suggests this may help
to increase player excitement.
3.5 Illusion of Control/ Skill
There is strong evidence that gamblers who are given an illusion
of control in a gambling game will value their chances higher than
those who feel they have no control. This is true even when the
gambler understands that the outcome of the game is completely
random. Langer  conducted a series of classic experiments in
which people bought tickets for an office raffle. Half of the
people chose their ticket number and half were just given a
numbered ticket. Later, Langer asked each person if she could
buy back the raffle ticket (she had made up a story as to why she
wanted to buy the ticket back). People who were able to choose
their tickets valued their tickets as being worth significantly more
than did those who did not get to choose their tickets, although
both groups clearly understood that the outcome of the raffle was
random. Thus, providing the player with choice even in an event
that is understood to be random has a powerful effect on the
Slot machines provide an illusion of control by allowing the
player to use a stop button. Slot machines work by generating
tens of thousands of random numbers per second, even when the
game is not being played. When the gambler presses ‘spin’ or
pulls the handle, the random numbers available at that instant are
used to determine the outcome instantly. However, the player has
to wait 5-6 seconds for the reels to stop spinning before he/she
knows the outcome. The games will often provide the player with
a stop button that stops the reels in two seconds or so. Gamblers
can often be seen hovering over the stop button and pressing it at
a particular instant as if they somehow are influencing the
outcome. Of course, pressing the stop button simply allows them
to see the result of the spin faster.
The use of a stopping device increases the perception that the
stopping is not random, but rather that there is some form of skill
involved: By having that control, there is an increased probability
of success, thus making the game more attractive to the player
. Nevertheless, these are illusive devices that fail to have an
actual outcome on the game. King et al describe that it is also
necessary, however, to have some degree of chance involved.
Events that cannot be controlled by the player increase the re-
playability and enjoyment of the game .
In Tetris, for instance, while the player must have the skill to
place the blocks in a way such as to eliminate rows, the choice of
where to place the blocks is open to the player. The skill is in the
selection of the placement of the blocks. The randomness occurs
in the actual block given to the player at each regular interval. A
player may hope for a particular block in order to clear a line, but
may be given a block that does not fit and causes a problem. Thus,
there is a degree of both randomness and skill involved in the
success of the player.
The lesson for the designers of casual games is that players may
enjoy an illusion of control that does not affect how the game
works but does potentially have a positive effect on the experience
of the player.
3.6 Bonus Rounds
Several authors have noted that the illusion of control or skill is
interrelated with the degree of personal participation
(involvement) in a machine [12, 24]. Nudge, holds, and other
buttons have increasingly found their way into slot machines,
along with bonus rounds that also give the illusion of skill. For
instance, a bonus round in Lucky Larry’s Lobstermania asks
players to select from one of a series of buoys floating in a lake.
Although the outcome is random, the use of choice (and therefore
the illusion of skill in selecting the correct buoy) is one example
of this use of illusion of control.
All modern slot machines have some type of bonus round. It is
entered randomly. When in bonus round the player always wins
something: It is always a positive experience. When in bonus
mode, the game may be free spins with added prizes or it may be
a completely different game altogether. Players consistently rate
the excitement of bonus modes as one of the most compelling
reasons why they choose one game over another .
On a larger scale, bonus rounds are often used in video games to
reward players for longer times spent with a game. The idea is
that when the player has mastered the technical skills required to
play the game, there are still rewards for continued play . The
skill in this case is the ability to discover these hidden levels or
sections of a game.
In casual games, bonus modes could come up randomly or in a
more predictable manner. For example, in between levels a bonus
round could occur. Instead of a cut-scene where the player is a
passive viewer, the cut-scene could contain three separate paths.
The player is given the choice of path A, B, or C. Depending on
the player’s response the player may gain few or many points. It
is still just a cut-scene but the player is experiencing an illusion of
control and is being rewarded with points.
Competitiveness is an important component of all games. This
involves competing against the machine, competing against
oneself, as well as competing against others. In slot machines, one
is always competing against the machine: attempting to beat the
odds. However, one is also in a sense in competition with others
on the casino floor. The perception that a big win on a machine
will somehow mean lower immediate future payouts is a popular
one. Gamblers will stick with one machine that has not paid out
recently in the hopes that the payout is coming. Moreover, the
attention paid to big winners on the casino floor is also in a sense
a form of competition.
Competing with the machine or against oneself of course involves
the illusions of control and skill discussed above. Competing
against others, however, has always been a particularly important
part of video games. Vorderer et al argue that competition is the
key determinant of a game’s enjoyment . They argue that the
outcome of competition is to increase the player’s self-esteem and
mood. Features such as high score tables (leader boards) are
critical to repeat plays, as players attempt to not only beat their
own score, but the highest score amongst their peers. Casinos and
lottery winners must allow their photos to be taken and displayed
inside the casino. The entrances to casinos all have such photos
with large cheques being handed to the winners, a concept which
is very similar to leader boards.
King and Delfabbro refer to this concept as ‘meta-game rewards’
that allow players to assess their overall mastery of a game by
comparing their results to others . Long-term or larger goals
are set by leader boards in order to increase playing time.
In traditional games of Tetris, players can gauge their success by
the leader boards in the game—typically only competing against
themselves or the small group of people who may have played on
that particular machine. Now that the games are networked, the
leader boards are more competitive and the issue of social
competition has become more important to casual games.
Facebook games, for instance, commonly post level up or score
information to all of one’s friends, encouraging entry and
longevity of play through competition.
This paper has outlined some of the key components that increase
playing time and player enjoyment on slot machines, and drawn
on Tetris to illustrate the practical implementation of these ideas
in casual video games. We summarize our main findings here:
• Rewards are intrinsic to video games, and as shown they can
take the form of points, auditory or visual rewards, and help
to increase the self-esteem of the player.
• Non-rewards or punishments provide enough of a frustrative
value to make the game interesting for longer periods of
• Rewards are tied to reinforcement schedules in which players
are kept interested through regular payouts of reward. The
timing and frequency of these rewards has been the subject
of decades of research, and while most games rely intuitively
on these schedules, more scientific approaches could be
taken to ensure playability.
• Illusory rewards are also important to keep player interest
while maintaining a degree of difficulty. Losses disguised as
wins at an approximate 20% ratio of overall play-time are
one example of these illusory rewards in slot machines.
• Near-misses at a 12:1 ratio encourage longer play times by
raising excitement levels.
• Skill and competition also play very important roles in video
games. Whether this is an actual skill or the illusion of skill,
the player’s perception of control is critical to the game.
• A degree of randomness or loss of control is also important.
The importance of this ratio of the chance to skilled element
remains unexplored and could be a valuable area of future
• As player skill increases, competition is important to
maintain motivation. Whether this is competition with the
game, or competition with other players, competition keeps
players interested in the game for longer periods of time. The
concept of ever-increasing difficulty and level of competition
is the key to Csikszentmihalyi’s concept of flow, or
immersion, popularly applied to video games.
We have shown that there is considerable research into gambling
and slot machines in particular that can be incorporated into video
game research. While video games have become incorporated into
gambling and psychology research (notably the work of King,
Delfabbro, Griffiths, and Wood), the inverse is not true. Video
game researchers—even those purporting to seek out the
properties that make video games ‘fun’ or ‘playable’ or more
‘immersive’ or ‘engaging’ (e.g.  )—have largely ignored
this important body of research and its empirical scientific work.
As discussed, some of the practice of game design is shared
between industries, and video game designers are sometimes
aware of the ongoing research in gambling. Denis Dyack,
president of Silicon Knights, for instance, stated in a private
discussion with two of the authors in 2008 that the idea of
reinforcement schedules was used in the Xbox 360 game Too
Human (2008). Researchers into video game design, therefore,
should be aware of this body of work on gambling and its impact
on game design.
By summarizing the key ideas, we have begun to introduce this
body of work to researchers. Moreover, these ideas form design
principles that can be incorporated into casual games, as well as
into the classroom environment when teaching game design.
Our thanks to research funding provided by the Ontario Problem
Gambling Research Centre, the Canadian Foundation for
Innovation, and the Social Sciences and Humanities Research
Council of Canada.
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