The PLEX Cards and its techniques as sources of inspiration when designing for playfulness

Abstract

Playfulness can be observed in all areas of human activity. It is an attitude of making activities more enjoyable. Designing for playfulness involves creating objects that elicit a playful approach and provide enjoyable experiences. In this paper, we introduce the design and evaluation of the PLEX Cards and its two related idea generation techniques. The cards were created to communicate the 22 categories of a playful experiences framework to designers and other stakeholders who wish to design for playfulness. We have evaluated the helpfulness of both the cards and their associated techniques in two studies. The results show that the PLEX Cards and its associated techniques are valuable sources of inspiration when designing for playfulness.

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nt. J. Arts and Technology, Vol. 6, No. 1, 2013
Copyright © 2013 Inderscience Enterprises Ltd.
The PLEX Cards and its techniques as sources of
inspiration when designing for playfulness
Andrés Lucero* and Juha Arrasvuori
Nokia Research Center,
Visiokatu 1, 33720 Tampere, Finland
E-mail: andres.lucero@nokia.com
E-mail: juha.arrasvuori@nokia.com
*Corresponding author
Abstract: Playfulness can be observed in all areas of human activity. It is an
attitude of making activities more enjoyable. Designing for playfulness
involves creating objects that elicit a playful approach and provide enjoyable
experiences. In this paper, we introduce the design and evaluation of the PLEX
Cards and its two related idea generation techniques. The cards were created to
communicate the 22 categories of a playful experiences framework to designers
and other stakeholders who wish to design for playfulness. We have evaluated
the helpfulness of both the cards and their associated techniques in two studies.
The results show that the PLEX Cards and its associated techniques are
valuable sources of inspiration when designing for playfulness.
Keywords: design methods; workshop; inspiration; playfulness; PLEX Cards.
Reference to this paper should be made as follows: Lucero, A. and
Arrasvuori, J. (2013) ‘The PLEX Cards and its techniques as sources of
inspiration when designing for playfulness’, Int. J. Arts and Technology,
Vol. 6, No. 1, pp.22–43.
Biographical notes: Andrés Lucero (PhD) is a Senior Researcher at Nokia
Research Center in Tampere, Finland. His interests lie in the areas of human–
computer interaction, user-driven innovation and design research.
Juha Arrasvuori (PhD) is a Senior Researcher at Nokia Research Center in
Tampere, Finland. His research work has involved topics such as playful
experience research, video games and interactive music applications.
This paper is a revised and expanded version of a paper entitled PLEX Cards:
a source of inspiration when designing for playfulness presented at Third
International Conference on Fun and Games 2010 (FNG 2010), Leuven,
Belgium 15–17 September 2010.
1 Introduction
Playfulness is a broader human phenomenon than playing games. Play is deeply rooted in
human culture, as proposed by pioneering anthropologist Huizinga (1955). Thus, it is
worthwhile to consider that most human activities, even pragmatic or mundane tasks, can
be approached and experienced to some extent as a form of play.

The PLEX Cards and its techniques as sources of inspiration 23
The terms ‘play’ and ‘game’ refer to two intertwined, but still different things. Some
scholars, including Frasca, use the terms ‘paidia’ and ‘ludus’ to define the difference
between play and game. Frasca has adapted these two terms from the seminal work by
Caillois (1961) whose original intent with the terms was to distinguish between free and
formal play. Paidia and ludus can be seen as the opposite ends of a broad range of
activities. Ludus is formal play with rules that define winners and losers, while paidia is a
type of play that does not do this (Frasca, 2003).
According to Fullerton et al. (2004), playfulness is a state of mind rather than an
action. Play can be a way of achieving new things because it allows people to look at and
approach things differently. A playful approach can be applied to mundane activities or
even serious subjects (Fullerton et al., 2004). A playful approach involves deriving
playful experiences from everyday activities and products. This definition of ‘play’
encompasses both ludus and paidia. Like paidia, being engaged in a playful approach
may not have a clear beginning, end and goal, and it may not even appear as a playful
activity to an outside observer. A playful approach means taking on any subject matter or
activity with the same attitude as in play: as something that is not serious and that does
not have real-world consequences. Through this approach, people obtain playful
experiences, in other words, experiences elicited by their playful approach to activities or
how they look at the world. Obtaining these experiences may per se be highly motivating.
Recently, designers and researchers have started designing for playfulness. Bekker
et al. (2010) apply three design values for playful interactions (i.e. motivating feedback,
open-ended play and social interaction patterns) in six design cases ranging from toy
battle-tanks controlled through body movements to objects that change colour when
shaken or rolled. Designing for playfulness has also been identified as an approach to
change users’ behaviour. Chiu et al. (2009) discuss how, by adding interactive elements
and using persuasive strategies, they turn an everyday object (i.e. a water bottle) into an
item for play that elicits adopting healthier habits.
Korhonen et al. (2009) have defined a playful experiences framework (PLEX). The
framework consists of 22 playful experience categories (Arrasvuori et al., 2010, 2011).
Both the PLEX and the mechanics, dynamics and aesthetics (MDA) (Hunicke et al.,
2004) frameworks aim at incorporating elements of playfulness in the design process as
means to achieve specific experiences. However, PLEX is not limited to explaining
experiences obtained from ludus-type activities, but it sets out to cover the entire play
continuum between paidia and ludus. The PLEX categories cover a broad spectrum of
experiences, some of which seem evident in play activities (e.g. ‘challenge’ and
‘competition’), while others may seem surprising in this context (e.g. ‘cruelty’ and
‘suffering’). We set out to explore if the PLEX framework could be used to design for
playfulness beyond games. In this paper, we introduce the design and evaluation of the
PLEX Cards. We created a set of cards to clearly communicate each of the 22 PLEX
framework categories and provide inspiration to designers while designing for
playfulness. Additionally, we propose two idea generation techniques that make use of
the cards: PLEX Brainstorming and PLEX Scenario.
This paper is structured as follows. Firstly, we provide background information on the
PLEX framework and discuss related work. Secondly, we introduce the design process of
the five versions of the PLEX Cards, followed by an evaluation of the final version of the
PLEX Cards. Thirdly, we present two idea generation techniques and the results of an
evaluation during a workshop. Finally, we provide a discussion and conclusions.

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2 PLEX framework
Costello and Edmonds (2007) have published one of the most comprehensive theoretical
frameworks of pleasurable experiences. They assembled the views of philosophers,
researchers and game designers to obtain what they call ‘pleasure framework’. They
derived 13 pleasure categories of play through cross-referencing six earlier publications.
The ‘pleasure framework’ is a fruitful starting point for the study of more specific playful
experiences. However, their framework mostly focuses on the evaluation of pleasurable
playful interfaces in interactive artworks.
To adjust and expand the framework, Korhonen et al. (2009) have added the works of
other researchers and designers to the pool of analyses, producing the initial version of
the PLEX framework. The added body of work discusses experiences, pleasures,
emotions, elements of play and the reasons why people play. The definitions presented by
Costello and Edmonds to their pleasure categories were also taken into account when
defining the PLEX categories. As a result of this analysis, the authors examine the wide
range of experiences elicited by interactive products when they are used in a playful
manner. The overall focus was shifted from pleasures to experiences to indicate that not
all such experiences are always pleasurable in the context of play. To validate the initial
PLEX framework, the authors interviewed 13 players about their experiences with three
videogame titles: The Sims 2, Grand Theft Auto IV and Spore. All the inspected PLEX
categories were mentioned on numerous occasions in the interviews and in the context of
at least two different games. The interview results indicated that the different ways in
which players experience games can at least partly be explained through the PLEX
categories. On the basis of the findings, the authors added new categories to PLEX. In
this paper, we explore the use of the PLEX framework as inspiration to design for
playfulness (Table 1).
Table 1 PLEX framework consisting of 22 categories
E
xperience
D
escription
E
xperience
D
escription
Captivation Forgetting one’s surroundings Fellowship Friendship, communality or
intimacy
Challenge Testing abilities in a demanding
task
Humour Fun, joy, amusement, jokes, gags
Competition Contest with oneself or an
opponent
N
urture Taking care of oneself or others
Completion Finishing a major task, closure Relaxation Relief from bodily or mental work
Control Dominating, commanding and
regulating
Sensation Excitement by stimulating senses
Cruelty Causing mental or physical pain Simulation An imitation of everyday life
Discovery Finding something new or
unknown
Submission Being part of a larger structure
Eroticism A sexually arousing experience Subversion Breaking social rules and norms
Exploration Investigating an object or
situation
Suffering Experience of loss, frustration and
anger
Expression Manifesting oneself creatively Sympathy Sharing emotional feelings
Fantasy An imagined experience Thrill Excitement derived from risk and
danger

The PLEX Cards and its techniques as sources of inspiration 25
3 Related work
We will now discuss other card decks that have been created for two main purposes: for
inspiration in design and as design games.
3.1 Design cards
Several designers and researchers have created a first group of cards whose main purpose
is to provide inspiration in user-centred design activities. Halskov and Dalsgaard’s
inspiration cards (2006, 2007) consist of two sets of cards (i.e. technology and domain
cards) that are used by designers and other stakeholders at the start of the design process
to generate ideas collaboratively. The designers themselves mostly define the contents of
the cards, although the stakeholders are invited to generate domain cards. The cards are
combined on A3 posters to capture design concepts. Buur and Soendergaard’s video
cards (2000) were created to allow developers to collaboratively and directly analyse bits
of videos collected in field studies. Short video sequences are first digitised and then
turned into playing cards. The cards are then used in the video card game where the video
resources are available to developers in a simple physical form. Brandt and Messeter
(2004) have developed four games that combine the use of three different types of cards:
1 Moment cards, a radio frequency identification-based implementation of the video
cards.
2 Sign cards, consisting of words to create stories and provide a conceptual framework
for these stories.
3 Trace cards or pictures of the surroundings collected from field studies.
The IDEO cards (IDEO, 2003) consist of a deck of 51 cards, each showing a different
method used by IDEO to keep people at the centre of their design processes. They are
meant to inspire creativity by inviting designers to try out and develop different
approaches when designing. The personal cardset (Sleeswijk Visser et al., 2005) is a
documentation of the different experiences reported by end-users in generative sessions.
The cards can be used to communicate the results of these sessions to designers. These
A5 cards contain a combination of raw data (e.g. user’s photo, name, quotes and
illustrations) and researchers’ interpretations (e.g. visualisations).
Our PLEX Cards share core aspects with the previously discussed design cards.
Firstly, the PLEX Cards help facilitate user-centred design activities when used by
researchers, designers and other stakeholders involved in the design process. Secondly,
the PLEX Cards were created as a rich source of inspiration for creative processes.
Finally, the PLEX Cards are a low-tech and approachable way to communicate the PLEX
framework categories.
3.2 Design-games cards
A second group of card sets has been created as part of design games to support idea
generation activities. Kultima et al. (2008) have designed two card sets to generate ideas
for mobile multiplayer games: the verbs, nouns and adjectives (VNA) cards and the
GameSeekers cards. The VNA cards consist of three decks of cards with one word, each
deck containing VNA. Analysing casual and children’s games helped pick the words. In

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this turn-based game, the first player takes one verb card, shows the card and describes
what is done in the game. The second player then takes a noun and elaborates on the
existing idea. The third player picks an adjective and completes the game idea by
merging the three elements together. This method generates several high-level ideas in a
short time frame. The GameSeekers cards is a set of four different types of colour-coded
cards with pictures, single words, sentences and abstract forms. The game itself is played
by dealing a number of cards to the players who then take turns in placing one card on the
table. The game ends either when one player runs out of cards or when all players have
passed their turn without adding something new to the idea. Compared to the VNA cards,
the rules of this game are more complicated and the resulting ideas are large and
shattered.
Two commercially available design-game cards are the Thinkpak and ThinkCube.
Michalko’s Thinkpak (2006) is a brainstorming card deck with 56 cards designed to
stimulate imagination, generate ideas and later evaluate the resulting ideas. Michalko
proposes a game for two or more people involved in group brainstorming. The players
pick up an idea stimulator card and must come up with an idea based on that card and
write it down within 2 min to avoid being disqualified. The game is over when there is
only one player left and the ideas can then be evaluated. Sampanthar (2007) created
ThinkCube by looking at board games and combining game mechanics with a
brainstorming card deck. The deck has 88 idea cards describing specific ideas, 88 word
cards with the definition of a keyword and a visual thesaurus, and 24 mutation cards with
verbs to modify the idea and word cards. The game is played by four to seven players
who each draw six cards from the idea library. Each player adds one card to the table so
that two or more cards can be combined together. A dedicated person writes down all the
ideas from the session. Similarly, our PLEX Cards incorporate simple game rules to
provide a structure to the innovation process. Participants take turns in drawing cards
from the deck and make combinations of categories to generate new ideas. The specific
dynamics of the idea generation game are later explained in this paper.
4 Designing the PLEX Cards
As part of the research on the PLEX framework, we wanted to explore if the categories
could be used as a starting point to design for playful experiences. We conducted three
design sprints where we used PLEX to guide design exploration. In each design sprint,
we used a different strategy to communicate the PLEX categories. Firstly, we briefly
projected a PowerPoint slide with the definitions of the categories on the wall. Secondly,
we printed an A0 poster with the definitions. Finally, we distributed PowerPoint handouts
with definitions and examples of the categories. Designers and other stakeholders
involved in these three design sprints were only able to have an overview of the
categories, as it was difficult for them to understand and grasp the meaning of the PLEX
framework from the different media we proposed. We needed to bring PLEX closer to
people.
The creation of the PLEX Cards was motivated by our need to clearly communicate
the different categories of the PLEX framework to allow designers to design for playful
experiences. We needed a low-tech and approachable medium that would better fit in the
dynamics of a design discussion. Physical cards were chosen for this matter. We will now
describe the design process of five versions of the PLEX Cards.

The PLEX Cards and its techniques as sources of inspiration 27
4.1 First version
4.1.1 Design process
The first version of the PLEX Cards consisted of 22 cardboard cards (Figure 1(a)). The
cards were squared (9 × 9 cm) and had round edges. To avoid a common physical
limitation of cards (Buur and Soendergaard, 2000), the front of each card had the name of
the PLEX category printed at the top and bottom in different orientations so that players
sitting on opposite sides of the table would be able to read the name of the card. The front
also included the textual definition of the category and one image aimed at illustrating the
main idea for that category. The back of the card was colour-coded red to identify the
version and had the name of the card deck.
As the origin of the PLEX framework is set on digital games, many of the images
were either directly related to videogames (Tamagotchi, Grand Theft Auto IV, The Sims,
Guitar Hero, Okami and Age of Empires) or other types of games (strip poker, fantasy
play and gambling). Other image sources were internet applications (Google Street View,
Nokia Sports Tracker and Google Earth) and TV shows (24, Itchy and Scratchy, Sex and
the City).
The cards’ contents (i.e. definition and images) had to succinctly and unequivocally
exemplify each category (Halskov and Dalsgaard, 2007). For this first version of the
cards, we did a thorough internet image search. We mostly used stock images of existing
commercially available products and a few faces of known people (e.g. Usain Bolt).
These images depicted moments, places and activities that create playful experiences.
Figure 1 First version and second versions of the PLEX Cards: the ‘expression’ card with its
long definition and a reference to Guitar Hero (a) and the ‘exploration’ card with an
image that suggests an action (b) (see online version for colours)
(a) (b)

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4.1.2 Evaluation
This version of the cards was tested in a first Social and Spatial Interactions (SSI)
workshop in fall 2009 in Tampere, Finland. A total of eight participants used the cards in
pairs to help them guide the discussion. The cards were drawn from the deck randomly,
discussing one category until they felt they needed to clear the table and take a new card.
Each pair went through four to six categories.
The findings show that the cards facilitated the process of introducing the categories
to those participants who were not familiar with the cards, as some knew the PLEX
framework beforehand. However, participants reported having problems relating to some
categories, as they were unfamiliar with the contents of the cards. Those cards that
referred to specific applications, TV series or games-related content were difficult to
understand if participants had not previously used those applications, seen those shows or
played those games. Straightforward categories such as ‘exploration’ had to be explained
several times during the workshops because most participants were unfamiliar with the
concept of ‘fog of war’ commonly used in map-based digital games. The same applies for
‘captivation’ and ‘challenge’, where a split-screen image from the TV series 24 was used
to illustrate captivation in narrative, and Nokia Sports Tracker was used to introduce the
idea of pushing your boundaries while exercising, respectively.
Other issues with the cards were related to the definitions and misleading content.
Some of the definitions were overly wordy and circular. For example, ‘fellowship’,
‘competition’, ‘nurture’, ‘challenge’, ‘control’, ‘expression’, ‘fantasy’, ‘eroticism’ and
‘relaxation’, all used the term as part of the definition. Regarding the misleading content,
some images created confusion as they could be linked to other categories. As an
example, the image for ‘nurture’ showed people meditating to suggest the nurture of
oneself, which was probably better suited for ‘relaxation’.
With this first evaluation of the PLEX Cards, we noticed the importance of finding
images that people can relate to. Halskov and Dalsgaard (2006) found with their
inspiration cards that when their technology cards were closer to the participants’ domain
of expertise, it allowed them to easily acknowledge the usefulness of the technology.
However, in our case, it is hard to judge beforehand what different people will be familiar
with in terms of specific technologies, applications, games or TV series. Therefore, we
needed to find some examples of content that would not be too specific so that most
people would be able to easily identify and begin their design exploration from.
4.2 Second version
4.2.1 Design process
Several modifications were introduced to the second version of the PLEX Cards
(Figure 1(b)). The shape and size of the cards were maintained, while the back of the
deck was changed to blue to reflect the version change. Out of the 22 cards, 14
definitions and 10 images were modified. The definitions were rewritten to increase
clarity and to remove circular definitions.
Regarding the images, we changed the most problematic ones as people could not
easily relate to them namely those that made reference to internet applications
(i.e. Google Street View, Nokia Sports Tracker and Google Earth) and TV shows (i.e. 24,
Itchy and Scratchy). We replaced them with examples of human activities or things
people do. For example, for ‘cruelty’ we replaced The Itchy and Scratchy Show for an

The PLEX Cards and its techniques as sources of inspiration 29
image of two small girls gossiping and leaving a third one out on her own. Two internet
applications were replaced for ‘challenge’ and ‘discovery’ by a group of children going
through a canopy walkway, and a child digging a large hole in the sand and finding
something in it, respectively.
At this point, we also started to introduce in the cards images that could potentially
suggest actions or lead to interaction styles. For instance Figure 1(b) shows a pair of
hands exploring a Rubik’s cube. To a trained interaction designer, this may suggest
twisting movements in opposite directions or rotating along the XYZ axis. Similarly, for
‘nurture’ two hands were holding a small bonsai tree by the base as if it was going to be
transferred from one pot to another. Again, the position of the hands and the action of
carefully transferring one object from one place to another may suggest interaction
techniques. ‘Sympathy’ and ‘thrill’ also could indicate new interaction styles as they
respectively depict a hug between two girls and a roulette dealer throwing the marble.
One final aspect of the card design is that we decided to remove the category name
found at the top of the card to allow players on opposite sides of the table to identify the
card. The reason for this was that the card had seldom been used in such an arrangement
and, due to the reduced size of the card, it was also adding extra visual information to the
card. We decided to have a simpler design.
4.2.2 Evaluation
The second version of the cards was evaluated with researchers from Helsinki Institute
for Information Technology (HIIT) in Espoo, Finland, in preparation for the EmoListen
workshop also in fall 2009. We thought it was relevant to confront this group of people
with the PLEX Cards as they would be using the cards later in the role of designers for
idea generation. A total of 14 researchers participated in this evaluation, who were split
into two smaller groups of 7. We used two decks corresponding to the first and second
versions of the PLEX Cards. The groups exchanged the cards so they would both be
exposed to the two versions. Participants first browsed the cards and then handled them
by pointing or taking a card in their hand to refer to specific aspects of the cards. They
also made clusters and associations as they openly discussed their own interpretations of
the material.
In general, the researchers were positive about the usefulness of the cards as they
helped to communicate the PLEX categories:
“(The cards are a) rich source for design inspiration. I can see this as a useful
tool for concept innovation.”
“These cards (make) a good card set. It made me to think a lot about
playfulness.”
Participants also pointed out that we should not limit the contents of the cards to games.
Although that had been our starting point, they told us we should rather rely on people’s
own experiences:
“(Having more) real-life examples might be better.”
The participants reflected on the fact that the images were working on different
abstraction levels. Although we had improved the deck by removing those images that
people could not easily relate to because they were too specific (i.e. internet applications
or TV shows), this time participants had trouble with images they had too strong opinions
about. The card for ‘competition’ had an image of Usain Bolt crossing the finish line in a

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100 m race. Participants knew Usain Bolt’s story beforehand so they said the image
strongly suggested ‘victory and domination’ to them, more so than competition. These
findings are in line with the work of Lucero (2009), and Sleeswijk Visser and Stappers
(2007). In his studies on how designers use mood boards, Lucero has found that designers
tend to avoid the use of pictures of famous people in their mood boards, as clients tend to
get sucked into the images and thus narrow down possible interpretations. Similarly, in
their work on personas, Sleeswijk and Stappers have found that images of famous people
come pre-packaged with messages, a set of values and norms, as well as other
connotations. Finding the right image for the cards relates to finding an appropriate
abstraction level for the contents. It is a delicate balance between being abstract enough,
so that the content does not dictate the design, and concrete enough, so that people can
relate to the content.
Participants asked us to avoid images that would be too detailed or that would over-
specify the design. They proposed having some sort of booklet or using the backside of
the card to reveal more abstract human experiences and then more concrete applications
or uses of the PLEX category.
In this second study, we identified the risk of using images that are pre-loaded with
meaning as they may narrow down the possibilities for new and unexpected
interpretations. Halskov and Dalsgaard (2006) have found with their technology cards
that the larger the conceptual distance is to the domain, the greater the innovative power
of the card.
4.3 Third version
4.3.1 Design process
The third version of the cards was the result of a major redesign (Figure 2(a)). Based on
the feedback we received from the discussion with researchers from HIIT in preparation
for the EmoListen workshop, we decided to change the squared shape of the cards to a
more traditional rectangular format (9 × 12 cm), still with round edges and an orange
backside. With this new card shape, we introduced a second image to the design. Having
two images there allowed us to play with the abstraction levels of the images (i.e.
abstract-concrete) and the contents (i.e. human emotion-application). The intention here
was to provide further entry points for designers to relate to the material and trigger new
ideas. If they were not familiar with a given application or object, they could rely on the
more general human-emotion or human-activity level. Similarly, if the content was too
broad, they could rely on the more specific image to begin their design exploration.
Content-wise, the 22 definitions were edited to send a clearer and more concise
message and 27 new images were introduced. Most of these new images were centred on
depicting a human-activity or emotional response, therefore giving the set a more human
and approachable character. We also continued the process of refining the content of the
existing images. We removed the reference to Usain Bolt as people made strong
associations with that picture. However, we were unable to take out the following
six references to famous people, TV series and digital games: Sex and the City for
‘fellowship’, The Sims for ‘simulation’, NintenDogz for ‘nurture’, Tamagotchi
for ‘suffering’, Grand Theft Auto IV for ‘subversion’ and Okami for ‘sensation’. Since
we had doubled the number of pictures to 44, we focused our search on finding new
material rather than revising the existing content in detail.

The PLEX Cards and its techniques as sources of inspiration 31
Figure 2 Third and fourth versions of the PLEX Cards: the ‘humour’ card with two images and
the new rectangular format (a), and the ‘control’ card (b). The top-half shows ‘human
emotions’ in an abstract way, with pictures of faces in black and white to focus on the
emotion. The bottom-half shows concrete examples from ‘everyday life’, with colour
pictures of hands suggesting possible interactions (b) (see online version for colours)
(a) (b)
4.3.2 Evaluation
The third version of the cards was tested in the EmoListen workshop with researchers
from HIIT in Espoo, Finland. This group had already participated in the evaluation of the
second version of the PLEX Cards. There were 11 participants involved who used two
PLEX Cards decks in a full-day workshop. They used the cards both individually and in
pairs.
Participants told us they preferred the new version of the cards with two images as
they gave more possibilities to connect with the content. The cards had a strong positive
impact in supporting idea generation during the design discussion:
“The PLEX (Cards) guided the concepting (process) heavily. It made me focus
on a single aspect.”
Participants commented on the role played by the cards as an object during the design
exploration:
“I find the cards useful for bookmarking thoughts and ideas.”
As Halskov and Dalsgaard (2006) have pointed out, the cards work as repositories for
statements and arguments, similar to the quote on using the cards as bookmarks for
thoughts. As a result of this, the cards become strong structuring elements of the
discussion. Buur and Soendergaard (2000) have found that people associate meaning to
each card, pointing at the cards as reminders of things to say or waving them to attract
attention to particular arguments.

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We also received feedback on some images and one definition (i.e. ‘humour’) that
were still leading to confusion. We had a short iteration of the cards and modified eight
of them. This time we got rid of most of the problematic references that were still
lingering in the cards (e.g. TV series, digital games, etc.), except Sex and the City and
The Sims as we were having trouble finding good replacements for those images.
Evaluations of this revised version are reported elsewhere (Lucero and Arrasvuori, 2010).
4.4 Fourth version
For the fourth version of the cards (cyan backside) (Figure 2(b)), the overall size and
shape of the card remained unchanged with respect to the previous third version.
Regarding the layout, on the front side we decided to maximise the space devoted to
the two photos by removing the white frame around the card. In this way, we hoped
people would be able to focus more on the images by perceiving more details in
the photos. We also moved the names of the categories to the top-right and bottom-left
corners of the card, so that people could hold the cards in their hand like they would do
with a traditional deck of playing cards.
There were two main reasons for making a next iteration of the cards, and they both
have to do with image content. Firstly, at different times we received feedback from the
evaluations saying that some of the images felt ‘stereotypical and uninspiring’. Studies on
using images to create personas (Pruitt and Grudin, 2003; Sleeswijk Visser and Stappers,
2007) have identified that using stock photos inevitably results in showing a stereotype
and in evoking a standard.
Slick stock images contain a polished set of presuppositions and prejudices. In
contrast, they have found that pictures of everyday people are natural, approachable and
more open for interpretation. Secondly, we wanted to be able to go public and freely
distribute decks of PLEX Cards while addressing the issue of copyright. For these two
reasons, namely having less stereotypical and copyright-free pictures, we turned to Flickr
and began a new search for more natural material under the Creative Commons
Attribution License (http://www.flickr.com/creativecommons/) that allows us to perform
derivative works of copyrighted photos provided, we credit them.
4.5 Final PLEX Cards
The fifth and final version of the cards (Figure 3) is available online (http://www.
funkydesignspaces.com/plex/). Up to this point, we had mainly concentrated on finding
the right language and content that would allow us to communicate the 22 PLEX
categories. Once we had produced a number of iterations of the cards and received
feedback on the different versions, we felt it was time to print the PLEX Cards in offset
so that others could start using them. We decided to redesign the overall look and feel of
the cards. The new version uses magenta as its main colour and VAG Rounded as its
main font instead of the more traditional Helvetica. The design for the back of the card
incorporates a playful pattern in magenta (Figure 3(a)). Additionally, we created two new
instruction cards that explain how the PLEX Cards can be used, and we also designed a
box that would contain all 24 cards (22 PLEX and two instruction cards).
Regarding the layout of the card, we did not introduce any further changes with
the exception of moving the category names to the top-left and bottom-right corners of
the cards (Figure 3(b)). We noticed that people were unable to see the category names

The PLEX Cards and its techniques as sources of inspiration 33
of the cards when holding the cards in their hands. We realised we had mistakenly placed
the category names in the opposite corners.
After five card iterations, now we had to look into detail at how the cards would be
used in practice. We have split that process into two parts. Firstly, in Section 5, we will
present an evaluation of the perceived helpfulness of the PLEX Cards during two
workshops (n = 27). Then, in Section 7, we will report the evaluations of two techniques
(i.e. PLEX Brainstorming and PLEX Scenario) during one workshop (n = 14).
Figure 3 Fifth and final version of the PLEX Cards. The design for the back of the card
incorporates a playful pattern in magenta (a). The overall layout of the front side of the
deck remains almost unchanged from versions three and four, except for the use of
VAG Rounded as the main font (b) (see online version for colours)
(a) (b)
5PLEX Cards evaluation
Two evaluation sessions were organised to assess the perceived helpfulness of the final
version of the PLEX Cards. In both sessions, the cards were used for ideation with
different techniques. The cards were evaluated both quantitatively (i.e. on a seven-point
Likert scale) and qualitatively (i.e. open-ended questions).
5.1 First evaluation session: SSI
The first evaluation was held in October 2010 in a Nokia Corporate Training Facility in
Nokia, Finland. The purpose of the workshop was to generate playful ideas for the SSI
platform (Lucero et al., 2010) allowing it to extend the current shared co-located
interactions with mobile phones to other physical and social use contexts (e.g. sharing
media content in a park, outdoor sports and multiplayer games).

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Fourteen participants with a mix of backgrounds (i.e. sociologists, designers,
engineers and psychologists) were actively involved in the workshop. The session was
arranged with participants from Mobile Life Centre and Nokia Research. All participants
were new to the final PLEX Cards. Participant familiarity with the PLEX framework
ranged between very familiar (n = 2), moderately familiar (n = 8) and unfamiliar (n = 4).
In previous workshops, the PLEX Cards had successfully been used as inspirational
stimulus, but in an unstructured way. This time we wanted the cards to be used in a more
structured manner. We introduced two idea generation techniques, PLEX Brainstorming
and PLEX Scenario, to structure the use of the cards in ideation sessions. These two
techniques are later introduced and evaluated in Sections 6 and 7, respectively. However,
for the evaluation’s current purpose of assessing the helpfulness of the cards, the reader
only needs to know that two structured techniques were used. The 14 participants were
split into 7 pairs. Each pair was given a complete PLEX Cards deck containing the 22
categories. Four pairs began the ideation with one condition (i.e. PLEX Brainstorming),
while the other three pairs began with the other condition (i.e. PLEX Scenario).Each
group roughly spent 30 min generating ideas using the corresponding technique twice,
after which they switched to the other technique for another two rounds creating more
concepts. Each participant used a total of 12 PLEX Cards; three cards in each of the four
rounds. After each round, the cards that they had used to generate ideas were removed
from the deck to avoid using a card more than once. In total, the idea generation session
lasted 60 min. The participants responded to the first half of a questionnaire after using
the first technique and to the latter half of the questionnaire after using the second
technique. The questionnaire is later explained in Section 5.3.
5.2 Second evaluation session: Emokeitai
The second evaluation was also held in October 2010 in the Media Centre Lume located
at the University of Art and Design in Helsinki, Finland. The purpose of the workshop
was to generate ideas for a service that encourages users to collect and share biosensor
data of their physical condition in a playful way. The organisers of the workshop wanted
to use PLEX Cards as stimuli to incorporate aspects of playfulness in the service.
Thirteen participants with different backgrounds (e.g. researchers, engineers and
psychologists) took part in the workshop. These participants worked at different
universities (i.e. HIIT, Helsinki School of Economics, Helsinki University and Aalto
University) or for different companies (i.e. Polar and Nokia). More than half of the
participants (n = 7) were new to both the PLEX framework and the PLEX Cards. The rest
of the participants had participated in the EmoListen workshop (Sections 4.2.2 and 4.3.2),
and thus were moderately familiar with the framework and an earlier version of the cards.
The idea generation session progressed as follows. The 13 participants formed 5
pairs, and 1 group of 3. Each group was handed out half of a PLEX Cards deck, in other
words, 11 randomly selected cards from a deck. As there were six groups, three full-card
decks were used. Each group placed the 11 cards face up on the table. Firstly, participants
picked one PLEX card and began generating and discussing together service ideas using
that category. After 4 min, participants were instructed to continue the exploration by
picking a new card. This process was repeated five times for a total of 20 min. Later, each
group picked up a sixth card and had 10 min time to consider the sixth PLEX category
and write a short description of the resulting service concept. Thus, the entire idea
creation session lasted 30 min. This first idea generation session had no other structure

The PLEX Cards and its techniques as sources of inspiration 35
than sequentially using 6 of the 11 cards that were randomly selected from the deck.
Finally, participants were asked to individually respond to a questionnaire once the group
idea generation had ended.
5.3 Quantitative results
We conducted both a quantitative and a qualitative evaluation of the PLEX Cards by
applying a similar questionnaire in the two evaluation sessions. Regarding the
quantitative part, we jointly calculated the mean ratings and standard deviations for the
first and second sessions (n = 27). In the first item of the questionnaire, we asked
participants about their general impression after using the PLEX Cards. The participants
responded on a seven-point Likert scale where í3 is very negative, 3 is very positive and
0 is neutral. The overall response was clearly positive (mean = 1.37 and SD = 1.04). Only
one participant responded to have a negative general impression by giving it a í2, while
two participants reported having a neutral general impression of the cards. Next, the
participants were asked to rate the helpfulness of each of the six PLEX Cards in thinking
about playfulness for the concept. The participants responded on a seven-point Likert
scale where í3 is very unhelpful, 3 is very helpful and 0 is neutral. We jointly calculated
the mean ratings on the helpfulness of the PLEX Cards from both workshops (Figure 4).
Generally speaking, participants were positive about the helpfulness of the individual
PLEX Cards. The mean ratings for the different cards ranged between 0.67 and 1.88,
except for ‘competition’ (mean = í1.00). The standard deviations ranged between 0 and
1.52, except for ‘eroticism’ (SD = 2.07), ‘relaxation’ (SD = 1.91) and ‘simulation’
(SD = 1.58). Regarding ‘competition’, we observed that in the Emokeitai workshop, two
participants reported using this category as the fifth card during idea generation, which
made it difficult for them to continue the exploration:
“The fifth card (‘exploration’) was hard to choose. It did not seem to bring
anything new to the concept” [P21].
Figure 4 Combined participant mean ratings and standard deviations on the helpfulness of
each of the PLEX Cards (see online version for the colours)
Ͳ3
Ͳ2
Ͳ1
0
1
2
3
Cap va on
Challenge
Compeon
Compleon
Control
Cruelty
Discovery
Ero cism
Explora on
Expression
Fantasy
Fellowship
Humor
Nurture
Relaxa on
Sensaon
Simula on
Submission
Subversion
Suffein
g
Sympathy
Thrill
MeanRa ngs
22PLEXCategories
HelpfulnessofthePLEXCards
1.631.13 Ͳ1.001.101.201.501.880.671.53 1.141.181.711.701.380.750.89 1.000.901.071.211.291.50

1.411.64 01.521.14.7 1.992.071.461.35 1.471.05 .821.19 1.911.051.581.451.331. 42.911.24

88410102176 15141717108 8 95101414 1412 

Mean


SD


N
Note: Error bars represent the 95% confidence interval of each mean.

36
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Regarding the high standard deviations for ‘eroticism’, ‘relaxation’ and ‘simulation’, we
have observed that some categories are very good at triggering people, but can in other
cases block the participants. ‘Eroticism’ is a clear case of such a category, where two
participants rated it with 3, and other participants gave it í1 or í2. This is inline with our
findings from previous studies (Lucero and Arrasvuori, 2010). Two participants working
together concentrated the negative ratings for ‘eroticism’ (í1 and í2) and ‘relaxation’
(both í2). One of them was critical about the cards in general:
“(The cards tend to) control my imagination too much, because I feel forced to
use them. Sometimes ideas rise from the (cards) too. I could use tarot cards to
get ideas too” [P20].
5.4 Qualitative results
Regarding the qualitative feedback, in general, participants positively commented on the
PLEX Cards’ role in supporting idea generation and guiding thinking about playfulness:
“(The cards) did kind of focus my usually chaotic brainstorming” [P24].
“Having these props ‘forces’ you to think of/consider the subject from a
varying set of aspects in a systematic way” [P22].
“I think a lot of their power came from the inspirational pictures rather than the
categories” [P6].
“It is good that the categories are so varied! I liked that” [P4].
Participants often mentioned that categories that could normally be considered
controversial in the context of playfulness (e.g. ‘eroticism’ or ‘cruelty’) were actually
helping participants to think in unconventional ways about playfulness:
“The ‘stronger’ cards such as submission and cruelty gave me a permission to
express some unconventional view. (…) I like the more controversial
categories like cruelty... they force you to take unconventional views” [P24].
“(The cards) brought up non-conventional configurations of those features,
even when not randomised. (…) Submission and fellowship forced to think
about the relation of the player to a larger context and not just the most obvious
single player option” [P26].
“(The cards) helped trigger ideas that may not have come otherwise. E.g. on
otherwise sensitive topics such as eroticism, suffering…” [P3].
One participant proposed that the PLEX Cards could be more stimulating if they had
more extreme examples of playfulness:
“(The cards) could be wilder in themes ... (Improve the cards by) widening the
theme spectrum, add strongly provoking concrete example cards” [P6].
Finally, participants proposed some future improvements for the card design, including
making the PLEX Cards more like playing cards and providing more options:
“Physically they could be more like real playing cards. (You could) slide
(them) over each other better and (they would be) easier to shuffle” [P1].
“If the backside was the same both right (side up) and upside down, you could
use the direction of the card as a random selection (which) could be useful in
some brainstorming techniques” [P10].
“Since the images formed the idea, it would be good (to) have different images.
Maybe more copies of each card or a digital version switching images” [P10].

The PLEX Cards and its techniques as sources of inspiration 37
6PLEX Cards techniques
As described earlier, the design of the PLEX Cards had positively evolved through the
different iterations. However, the actual use of the cards had remained unchanged.
Participants would work in pairs, drawing one card from the deck to generate ideas until
they felt they could no longer come up with new ideas. To explore alternative uses of the
PLEX Cards that structure the innovation process, we developed two idea generation
techniques: PLEX Brainstorming and PLEX Scenario.
6.1 PLEX Brainstorming
The first technique is PLEX Brainstorming. Although the term ‘brainstorming’ has had a
precise definition in reference to the technique originally used since 1930s, nowadays the
term can refer to different settings of group idea generation (Kultima et al., 2008). PLEX
Brainstorming aims at rapidly generating a large amount of ideas.
Participants of the idea generation session are split into pairs. Each pair is handed a
deck with 22 PLEX Cards. The first participant randomly picks one card from the deck
and places it face up on the table so that both participants can see the card. This card
becomes the seed card. Both participants draw three extra cards from the remaining 21
PLEX Cards available in the deck.
Participants look at their own cards, but not at the other’s. The first participant begins
explaining the idea on basis of the seed card. The second participant listens and considers
the categories in his/her own cards. When the second participant feels that she/he can
elaborate further on the idea, she/he takes one card from his/her hand, puts it down on the
table and explains how it changes the initial idea (Figure 5(a)). When the first player
thinks that she/he can continue with the idea based on the cards in his/her hand, she/he
picks another card and places it on the table. After all three cards have been dealt on
the table participants can freely discuss the idea. Based on the three cards available on the
table, both participants agree on what the idea is about and write a description of it. Once
all cards have been put back in the deck and the deck has been shuffled, then
the participants can start a new idea generation process.
This technique was inspired by the VNA cards game (Kultima et al., 2008). The
difference is that in PLEX Brainstorming, both participants initially have three random
cards in their hands as opposed to one random card in VNA. This gives participants
involved in PLEX Brainstorming some choice over which card they place on the table
and use to extend the idea originating from the seed card. Although it does not define a
winning condition, PLEX Brainstorming can be seen as a game because it is an activity
bounded by rules (i.e. the procedure). Kultima et al. (2008) note that rules make the idea
generation game progress in an orderly fashion, and turn-taking provides equality for all
the participants to contribute. The conceptual setting of a game can create a tension that
becomes a driving force, where everyone wants to succeed. These factors facilitate idea
creation.

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Figure 5 In PLEX Brainstorming (a), the second player (top) elaborates on the idea that
originated from the seed card by placing one of his cards on the table. In PLEX
Scenario (b), participants start with seven random cards open on the table
(see online version for colours)
(a) (b)
After we had used PLEX Brainstorming for a while, we found an issue with idea
documentation. The idea changes dramatically, as new cards are laid on the table and are
often completed after the last card has been shown. Only then it is documented. Unless
the entire session has been recorded, interesting aspects stated in the beginning of the
session may be left out of the documentation.
6.2 PLEX Scenario
The second technique, PLEX Scenario, aims at generating more ‘complete’ idea
descriptions in a short period of time, focusing on the quality and full-roundedness of the
created ideas. Participants involved in the preparation of the first design case suggested
the use of a game board to us, when we presented the first and second versions of the
PLEX Cards. Another inspiration for this technique was the GameBoard idea generation
game (Kultima et al., 2008).
Similarly to the PLEX Brainstorming, participants of the idea generation session are
split into pairs. Each pair randomly selects three PLEX Cards from the deck of 22 cards.
Using an A3 template (Figure 6), participants create a scenario using the three cards. The
scenario (or ‘use story’) is first triggered by an action related to the first card, then it is
developed further with the second card and it is finalised with the third card. Participants
are allowed to change the order in which the cards were initially drawn, until they find a
combination that helps them to build a scenario. The scenario is documented on the
template either as text or sketched as a three-frame cartoon strip.
In a variation of the technique (Figure 5(b)), participants first randomly pick seven
cards and put them face up on the table. The participants then create the scenario by
selecting three of these available cards and place them in the order they choose.

The PLEX Cards and its techniques as sources of inspiration 39
Figure 6 The PLEX Scenario template. Questions on the template guide the scenario creation
(see online version for colours)
7PLEX Cards techniques evaluation
The PLEX Brainstorming and PLEX Scenario techniques were evaluated during the SSI
workshop described in Section 5.1. As mentioned previously, 14 participants were split
into 7 pairs. Each pair was given a final version of the PLEX Cards deck. The idea
generation started so that in the first 30 min four groups went through two rounds of the
PLEX Brainstorming technique to create concepts, while the other three groups used
the PLEX Scenario technique twice. After that, the groups switched to use the other
technique for an additional two rounds. In total, the idea generation session lasted 60 min.
The procedure for PLEX Brainstorming was as described in Section 6.1, with the
exception that the first participant or player picked the seed card from their hand instead
of the deck. PLEX Scenario was adapted so that in the first round using the technique, the
three cards were selected randomly. In the second round, seven cards were randomly
drawn from the deck and placed face up on the table so players could pick three of them.
Three PLEX Cards were used in each round to create a concept. The used cards were
removed from the deck. Participants were asked to fill-in questions related to the two idea
generation techniques once they had all completed four rounds using the techniques.
7.1 Quantitative results
Regarding the quantitative part, we asked participants to rate their general impression
upon using the PLEX Brainstorming and PLEX Scenario techniques. The participants
responded on a seven-point Likert scale where í3 is very negative, 3 is very positive and
0 is neutral. Participants were positive about both techniques with a slight preference
for PLEX Scenario (mean = 1.43 and SD = 1.45) over PLEX Brainstorming (mean = 1.36
and SD = 1.15). Only two participants rated the techniques negatively by giving
them í1 or í2.

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7.2 Qualitative results
As stated earlier, participants were equally divided in their preference for both the
techniques. Those who preferred the Scenario technique often mentioned the structured
approach better suited their way of working:
“Fun, easy. Sometimes hard to start. Overly easy to finish. Excited to see
stories evolve quickly” [P1].
“I like (Scenario) better because it is more structured and directed (…)
especially to begin with (idea generation)” [P2].
“(It was) a bit challenging to think of (an idea to have) a beginning,
continuation and end. But it made the ideas very concrete” [P4].
“(Scenario) adds a twist to the thinking. Playfulness derives mostly (from) the
combinations and arrangements. The structure is very important” [P8].
The rest of the participants preferred the Brainstorming technique. The main reason was
that they felt it was faster and more flexible:
“I preferred the ‘looser’ one in the beginning, rather than the story structure.
(It) may not need that much structure apart from the cards” [P3].
“(The Scenario technique was) slower and more vague than the Brainstorming
technique. Perhaps a different structure might work better” [P9].
“(In Scenario), the first card formed most of the idea. We used (the technique)
pretty linearly, I think it would be useful to jump back and forth (between the
picked PLEX categories) a bit more” [P10].
Finally, participants identified a general problem with both techniques. As with any
ideation method, it is of utmost importance to clearly define a task or design problem:
“(You) need a good clear question to begin. The best ideas came when there
was a ‘fuzzy’ idea in the beginning, and it got clearer along the way” [P10].
“(It) misses the first step: setting up a situation (e.g. a park with three friends
who are bored)” [P13].
8 Discussion
8.1 Designing for playfulness
Based on Fullerton et al. (2004), we have defined playfulness as a state of mind and as an
approach to an activity. In our discussions on playfulness during the design sprints, it
became apparent that playfulness is foremost a state of mind that provides enjoyment. In
most cases, this enjoyment arises from doing (everyday) activities in a way that is
different from how they are usually performed (e.g. typing a phone number in a
rhythmical pattern). These actions may not be planned in advance or last for very long.
We understand playfulness as a spontaneous enjoyment arising from an action.
Designing for playfulness would then involve designing for minor actions that people can
perform impulsively and with little effort, and that provide enjoyment. This differentiates
designing for playfulness from game design as the latter is involved with creating
systems with rules and content.

The PLEX Cards and its techniques as sources of inspiration 41
8.2 Implications for the PLEX framework
The current set of 22 PLEX categories makes it difficult to design for playfulness in an
efficient way. In the design sprints, it came to our attention that some of these categories
relate on an action-consequence dimension. For example, one could argue that
‘exploration’ leads to ‘discovery’ or that ‘completion’ is a motivation to reach an end
state but not something you can design for. The way the PLEX categories are currently
defined, some of them define actions, while others define consequences. Dividing the
PLEX categories according to action and consequence would reduce the number of
categories describing actions eliciting playfulness to 12: ‘challenge’, ‘competition’,
‘control’, ‘cruelty’, ‘eroticism’, ‘exploration’, ‘expression’, ‘fantasy’, ‘relaxation’,
‘subversion’, ‘sympathy’ and ‘thrill’.
8.3 PLEX techniques
Regarding PLEX Brainstorming and PLEX Scenario, we received both positive and
negative comments on the techniques. Some participants considered that the structured
approach provided concrete results, while others felt turn-taking, selecting three cards
and building the idea from a seed card blocked their creativity. We have to conduct
further experiments that include variations to both techniques (e.g. number of cards
picked and used, number of participants, etc.) before we can say anything conclusive
about their effectiveness in comparison to other design methods.
9 Conclusions
The domain of playfulness is much broader than just games: potentially any activity can
be approached and performed in a playful manner. The aim of designing for playfulness
is to create objects that elicit a playful approach in the user and provide enjoyable
experiences from using them. We have designed and evaluated five versions of the PLEX
Cards based on the 22 categories of the playful experiences. Designers and other
stakeholders who wish to design for playfulness can use the cards.
Additionally, we have proposed PLEX Brainstorming and PLEX Scenario as two
accompanying idea generation techniques for the PLEX Cards. We have evaluated the
practical use of the cards and the techniques in two design workshops. The results
suggest that the PLEX Cards are a valuable source of inspiration when designing for
playfulness. The PLEX Brainstorming technique helps to generate a large amount of
ideas in a short time, while the PLEX Scenario technique facilitates creating more
elaborate ideas. Our results also indicate that in order for the PLEX Cards techniques to
be effective as ideation methods, it is of utmost importance to frame the design problem
by setting a clear task or context. Future work includes further testing the effectiveness of
the two techniques as design methods.

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