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Conceptual, Communicative and Pragmatic Aspects of Interaction Forms - Rich
Interaction Model for Collaborative Virtual Environments
Tony ManninenDepartment of Information Processing Science, University of Oulu, FINLAND
Abstract
This paper provides a form-oriented description and
applicable model of interaction in the context of
Collaborative Virtual Environments (CVE). The
construction and the main categories of the conceptual
interaction form model are described through examples
and previous work. The evaluation and validation of the
model is illustrated by delineating the research process
conducted by the author. Furthermore, the benefits and
limitations of the model are discussed in the light of CVE
analysis and design.
1. Introduction
The lack of intuitive and non-intrusive non-verbal cues
is one of the distinctive features that separates computer-
mediated communication settings from face-to-face
encounters. One solution to the interaction problems is the
CVE design approach that draws from the theories and
conceptual models of available interaction forms. Theinteraction form model, which has been constructed
during this research, directs the design to start from the
natural areas of interaction. By taking a holistic view of
the concept of interaction forms, the model enables
designers to take into account all the necessary
manifestations and representations of interaction.
The aim of this research is to conceptualise and
delineate the mutually perceivable interaction forms
available for avatar-based CVEs. Interaction forms are
actions that can be perceived as manifestations of the
user-user and user-environment interaction. These forms
are used to convey the actions of the user to oneself, and
to others. The forms enable awareness of actions byoffering mutually perceivable visualisations and
auralisations within the virtual environment.
The scope of this work covers the manifestations of
interaction. The emphasis is on every action and
interaction that can be perceived in CVEs. The mutually
perceivable actions and behaviours have been described
without tackling the social or cultural aspects of
communication, co-ordination and collaboration. The
point of interest, thus, is to find more understanding about
the possibilities and effects of rich interaction in the CVE
context.
2. Theoretical background and related work
The forms of interaction have been described and
discussed in the existing literature in the field of
communication, for example, under topics such as non-
verbal communication channels and communication
codes [2, 8, 10]. The focus and starting point for these
models is on the face-to-face interaction between humans
who share the same physical place.
Within the context of computer-supported co-operative
work (CSCW), the focus of research is not limited to
specific communication channels. One area of interaction
research relates to the embodied actions that cover the
movements and actions of the participants who interact
with each other and with their environment [16].
However, the interaction forms described in this paper
only exist in virtual environments, and thus, the actions
occurring in the physical world are out of the scope of this
paper.
The concept of rich interaction is not only a
quantitative measure describing the amount of available
interaction forms [8]. However, a basic set of interaction
form categories helps the CVE designers to consider all
the necessary areas of action representations. Rich
interaction can be enabled by a set of interaction forms
which is large, flexible and focused on the content. The
contextual and communicative support for interaction is
essential in providing users with meaningful ways to
express themselves and their actions. The richness itself
is, at the end of the day, achieved by users who are able to
exploit the available interaction forms in an intuitive and
non-deterministic style.
The related research of interaction forms covers a wide
area, ranging from CVE design to communication and
collaboration support. This section outlines some of the
previous research that is closely related to the line of work
described in this paper.
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Benford et al. [4] have created a spatial model of
interaction which provides a basic set of abstractions for
managing interactions in a wide range of spatial systems.
The authors argue that the spatial model of interaction
provides a novel and powerful set of abstractions for
managing interactions in a variety of large-scale virtual
spaces. However, the model does not imply any specific
interaction forms that could be used, for example, to
represent and execute participants aura, focus and
nimbus.
Robertson has constructed a taxonomy of embodied
actions [16], which consists of individual actions (in
relation to physical objects, other bodies, and to the
physical workspace) and group activities constituted by
individual embodied actions. While Robertson's
taxonomy does not contradict the model presented in this
paper, the level of abstraction is different. Robertson
delineates actions that describe the incentive of the
participant. Furthermore, there are actions that can be
presented with various interaction forms.
Additional descriptions of modes and types of
interaction have been presented, for example, in the areas
of autonomous agents [9]. The non-verbal communication
aspects of CVEs have been studied, for example, in the
context of user embodiment [3], communicative
behaviour [18], conversational interface agents [6], and
realistically expressing avatars [17]. These approaches,
however, tend to concentrate on a highly specific and
limited interaction support.
The approach selected by this author follows, to a
certain degree, the lines of the related research. The
interaction form model has been constructed in order to
obtain a clear overall picture of the concepts related to
interaction. The basic theories have been selected from
the areas analysing physical world communication in
order to enable the continuum in the level of
communication. In addition, the relatively mechanistic
perspective to interaction (i.e., the focus is on forms
instead of functions) is believed to enable user-driven
communication, control and collaboration.
3. Construction of the model
The interaction form model has been constructed by
collecting theoretical knowledge (e.g., communication
literature) and empirical material (video recordings,interviews, walkthroughs, observations, and heuristic
evaluations) from networked games, game events and
from self-organised gaming sessions [12].
The main aim of the model is to provide as exhaustive
a set of interaction forms as possible. However, due to the
high number of available interaction forms, the model is
structured into several main categories, which, in turn,
contain a number of sub-concepts.
The starting point for the conceptual modelling was the
interaction form support offered by the existing CVEs. In
order to acquire a basic set of currently available
interaction forms, a number of contemporary multi-player
games have been studied and the material has been
expanded with heuristic evaluations [18, 19]. The games
that were observed include, for example, a 3D multi-
player action game called Counter-Strike. Additional
games that have been studied include action games (e.g.,
Action Quake, Team Fortress) and role-playing games
(e.g.,EverQuest, Ultima Online). Some material was also
obtained from text-based games and flight simulators.
The next step in constructing the concept model was
the categorisation of different interaction forms. The basic
criteria for categorisation were the closeness and relations
of different sub-concepts. For example, all the interaction
forms that relate to the appearance of the avatar were
grouped together. The construction was based on the
conceptual analysis, and thus, offered a somewhat
coherent illustration of the corresponding interaction
forms. The first versions of the model were constantly
refined and revised according to the additional
evaluations of games and other CVEs.
The theoretical framework that would support the
aforementioned preliminary model was applied on a later
stage. Before the integration, the preliminary model was
used as a basic design guideline in constructing an
empirical experiment called Tuppi3D. The experiment
was then evaluated by using the synthesised model of
non-verbal communication channels (hereinafter referred
to as NVC) described in the communication literature (cf.
[2, 8, 10]). The perceivable interaction forms encountered
in the Tuppi3D experiment were analysed based on the
NVC model. Manninen and Kujanp [14] have
elaborated on the experiment and the outcome of the
analysis.
After the analysis of perceivable non-verbal
communication forms in the experiment, the concept
model was modified in a way that the structure of non-
verbal communication forms created the backbone of the
model. The categories from the preliminary concept
model were then added to the base model. The combined
model, thus, covers a wider range of interaction forms.
Furthermore, it takes into account the aspects of virtual
environments by also describing the forms that are not
necessary applicable in physical world interactions.
4. Description of the concepts in the model
Figure 1 represents the first layers of the
decomposition that forms the proposed concept model of
interaction forms. The map illustrates the main interaction
types that can be found within current multimedia games.
The forms have been categorised into 12 classes, each
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consisting of a number of sub-concepts. The basis for this
taxonomy is the categorisation of various interaction
forms in terms of communication channel, context, and
acting entities (e.g., body parts, environment, fellow team
members, etc.).
INTERACTION
FORMS IN CVEs
Avatar
Appearance
Kinesics
Autonomous
AI
Artefacts
Language-based
Communication
Physical
Contact
Setting
Physique Equipment
Clothes
Postures
Environmental
DetailsFollow-me
Auto-actions Reflection
Use of
Object
Object
Exchange
Destruction
Construction
ObjectMoving
Tactile
DefensiveSignals
Emotional
Agressive
BodyMovement
ChatSpeech
Phrases
SignLanguage
Modification
Non-verbal
Audio
Sound
effects
Silence
MutualAffects
Face & SkinHair Adornment Paralanguage
OlfacticsChronemics
Spatial
Behaviour
Orientation
Positions &Locations
Proximity &Distance
HeadMovement
Gestures
Facial
expressions
Music
OcculesicsEye
Movement
Visual
Orientation
Eye
Contact
Figure 1. Concept model of interaction forms.
It has been attempted to keep the naming of the sub-
concepts within the level of interaction forms without
describing the functions that can be executed by using the
forms. However, there are some sub-concepts that can be
considered as styles of interaction. For example,
emotional physical contact does not imply any specific
interaction forms. It merely directs the thinking towards
the instances of emotional forms, such as hugging, petting,
holding hands, etc. In relation to this, the consistency of
the model is compromised. Still, the naming convention
aims at providing as clear a tool for analysis and design as
possible.
The following section illustrates the forms, or
manifestations, of interaction. A brief description of each
of the main categories is provided. The model does not try
to replicate the physical world interaction forms. The
relation to the physical world is taken into account when
applicable, but the potential of virtuality is also harnessed.
Autonomous AIcategory includes a set of pre-
programmable actions and reactive behaviour that
resembles subconscious and intuitive actions in the
physical world. Some of these actions can be regulated by
the system while others are modifiable by the participants.
This group of interaction forms overlaps with most of the
other categories. However, the autonomous actions are
considered as a separate group because of the specific
nature of most of the actions and their importance in terms
of design.
Avatar appearance defines the attributes of image and
presentation of self [8, 10]. Appearance contains the
visual aspects of one's presentation. Argyle [2] divides
this into two: those aspects under voluntary control -
clothes, bodily paint and adornment - and those less
controllable - hair, skin, height, weight, etc. The aspects of
appearance can, thus, be thought of as static or dynamic
communicational messages, depending on the attribute.
The CVE context enables novel ways of utilising
appearance as a form of interaction because the physical
constraints are not necessarily replicated from the real
world. For instance, avatar size and shape can be
dynamically altered in order to convey particular
messages. The Tuppi3D experiment included only static
representations of avatars that conveyed the identities of
the players. However, the participants felt that they would
have liked more freedom in customising their visual
images. A dynamic way to change ones appearance was
considered as effective channel for communicating.
Chronemics involves the use and perception of time
[5]. Masterson [15] describes the example of being
punctual versus being late as one illustration of this group.
However, there are several other possibilities in using time
as a communication tool. For example, pauses can be used
to increase anticipation and to make others pay closer
attention to ones actions. The interaction analysis of
Tuppi3D [14] suggested that the chronemical forms
emerge when there is flexible set of various interaction
forms available for the participants.
Facial expressions may be broken down into the sub-
codes of eyebrow position, eye and mouth shape and
nostril size. These, in various combinations, determine the
expression of the face, and it is possible to write a
'grammar' of their combinations and meanings [7].
Furthermore, Argyle [2] classifies blushing and
perspiration as facial expression.
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Although face is the most significant channel of non-
verbal communication in physical world, the virtual
environments tend to diminish the role of face due to
graphics resolution limitations. However, in close
encounters and discussion-oriented situations the facial
expressions are fully perceivable even in games and
CVEs.
Environmental details define the appearance of
surroundings providing contextual cues [15]. These
include artifacts that can be used and manipulated within
the environment [5]. Argyle [2] states that moving objects
and furniture, leaving markers, and architectural design
can be used to communicate through space and place. The
mutual affect involves the effect environment has on the
user and vice versa. For example, physical boundaries
(e.g., walls), lighting (e.g., shadows), and the matter
filling the virtual space (e.g., water) can change the
performance of the participants. The dynamics of the
setting vary according to the implementation. However,
usually at least a restricted destruction and modification of
the environment is allowed.
Kinesics includes all bodily movement commonly
referred to as body language [5]. Head movements are
involved mainly in interaction management, particularly
in turn taking in speech, and can consist of one or several
sequential (rapid) nods at various speeds [7]. Posture
defines the way of sitting, standing and lying [2]. Gestures
involve the hand and arm as the main transmitters, but
gestures of the feet and head are also important. They are
usually closely co-ordinated with speech and supplement
verbal communication.
Computer games support kinesics relatively well. There
are numerous examples of crawling, walking, running,
jumping and waving animations that portray the action of
the player.
Language-based Communication is the major channel
for interpersonal information sharing in most of the
current CVEs. The use of language, or symbols, can be
modelled and conveyed textually, aurally, and in the form
of images. Text chat and voice-over-IP speech support are
examples of the channels that support this group of
interaction forms. Although language itself is not within
the focus of this work, the level of language abstraction
and automation is highly relevant. Speech audio with
spatial auralisations represents the level of highest
'manual' control. Instead, pre-programmed phrases and
textual parser support represent a somewhat abstracted
and automated utilisation of language.
Non-verbal audio includes the use of voice in
communication, which is often referred to as
paralanguage [5]. The non-verbal aspects of speech
contain prosodic and paradigmatic codes [7]. The former
is linked to speech (e.g., timing, pitch, and loudness) and
the latter are independent of the speech (e.g., personal
voice quality and accent, emotion, disturbances). Non-
verbal vocalisations [2] are an essential part of
communication as they can significantly change the
meaning of the message. In addition to these, CVE
systems can contain various sound effects and background
music that can be used as manifestations of interaction.
Furthermore, successful, i.e., purposeful, silence is a
strong form of interaction that often causes problems in
networked settings because of lag (e.g., communication
partner does not mean to be silent but the network lag
makes this happen).
Occulesicsare movements of the eyes, e.g., gaze [15].
Eye movement and eye contactdepict the focus, direction
and duration of the gaze in relation to other participants
[7]. Allbeck and Badler [1] use the term visual orientation
to differentiate occulesics from spatial behaviour. Argyle
[2] describes two groups of variables associated with the
gaze: amount of gaze (e.g., how long people have eye-
contact) and quality of gaze (e.g., pupil dilation, blink
rate, opening of eyes, etc.). In CVEs, the effective use of
this category requires modelling of eye movements and
detailed enough visuals.
Olfactics refer to the non-verbal communicative effect
of one's scents and odours [15]. Perhaps the most common
example of this category is the use of perfumes. This
group is not widely supported in CVEs, because of the
user-interface limitations. However, there are examples,
especially in games, of the successful application of
simulated olfactics as an interaction form.
Physical Contactreflects the use of touch in
communication situations [5]. This category consists of
actions such as handshakes and patting [1]. Furthermore,
bodily contact stimulates several receptors that are
responsive to touch, pressure, warmth or cold, and pain
[2]. In the context of CVEs, this group consists of virtual
interaction between the avatars of the participants.
Spatial behaviour consists of proximity, orientation,
territorial behaviour and movement in a physical setting
[2]. Burgoon and Ruffner [5] use the term proxemics to
include actions relating to the use of personal space.
Proximity consists of the various actions corresponding to
the use of personal space, i.e., how closely we approach
someone can give a particular message about our
relationship. Different distances usually convey different
meanings. Orientation defines the direction to which a
person has turned to. This code conveys information about
our point of interest, or, focus [7].
5. Evaluation of the model
The usefulness of the interaction form model has been
evaluated in two ways. First, the model has been used as a
framework for analysing the existing CVEs. Second, the
model has been used as a design guideline in constructing
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new CVE experiments. The evaluation has been
conducted in an iterative manner. The results of previous
evaluation have been used to refine the model, which, in
turn, have then been used as a framework for further
analyses.
The preliminary version of the model was used as a
framework in the analysis interaction forms perceivable in
multi-player game sessions [11]. The results of the study
indicate the successful application of the model as a tool
for structuring the data into coherent and descriptive
categories. Furthermore, the model was helpful in pointing
out several areas of interaction forms that were not
adequately supported by the systems.
The model was analysed and compared against the
social theoretical framework [10]. The different
approaches to interaction (i.e., the interaction form
approach and the higher-level social action view)
adequately supported each other. The model of interaction
forms was successfully mapped as a set of executing
instances for the higher-level social activities.
The next phase in the evaluation was the design and
development of the Tuppi3D experiment. The interaction
form model was used as a design guideline in constructing
a CVE that would support rich interaction. A qualitative
video analysis was then conducted by using the NVC
model as the framework. The results indicated that the
purely communicational NVC model does not represent a
complete set of interaction forms [14]. Based on this, the
interaction form model and NVC model were combined in
order to obtain a holistic view towards the concept of
interaction.
The earlier interaction form analysis of multi-player
games was re-evaluated using the final version of the
model. The results indicated that the findings support the
new model relatively well. There were no interaction
forms that did not fit into the framework. On the contrary,
the model illustrated several concepts that were not
evident in the current data [13].
The final evaluation of the model was conducted from
a process point-of-view in a research project which
focused on a value-added service production for mobile
platforms. The importance of non-verbal communication
in multi-player game environments was successfully
brought forward and demonstrated in theory (i.e., the
concept model) and in practice (i.e., the experiment).
Furthermore, the rich interaction model and the
corresponding design philosophy led to a solution that
was, in many ways, superior to the solution designed and
developed purely with the technological focus.
The holistic approach to a complex phenomenon, such
as interaction forms, makes the modelling difficult
because the models may grow to be too large. There are
hundreds of specific interaction forms that can be applied
to the CVE context. Successful illustration of all these
concepts may prove to be a relatively difficult task. Still,
categorisation of the concepts enables the coherent
breakdown of the model into a set of sub-models that can
be considered individually.
The nature of multi-player games maintains the level of
abstraction relatively high, so, for example, the detailed
direct manipulation and complex artefact sharing that are
common in numerous groupware applications may not be
fully supported. Nevertheless, this type of interaction can
be illustrated with a set of corresponding interaction
forms.
Although the model is useful in analysing and
understanding the concept of interaction forms, it is
difficult to design and implement CVEs based on the
model alone. The implementation generally requires
abstraction, which, in turn, forces the designers to
consider higher levels of interaction. This may lead to a
traditional top-down design approach, in which the
available interaction forms are suffocated by the higher-
level activities [12].
The usefulness of the model is in providing a
conceptual framework that can be applied as a basis for
the analysis, evaluation and design of CVE applications.
The model can aid the designers to support meaningful
and useful interaction by providing a holistic view to the
applicable interaction forms. Furthermore, the conceptual
understanding of the phenomenon helps the researchers
and practitioners to tackle the issues of interaction design
collaboratively because it provides a common language
and terms for the various interaction form categories.
Due to the somewhat mechanistic approach, the model
serves well as a basis for lower level interaction support.
The focus being on forms, and not on functions, makes it
possible to design a number of interaction forms that
support numerous functions. The aim is not to dictate how
the participants should exploit the available forms of
interaction. Instead, the goals and incentives of the users
can be well supported by the lower level manifestations of
interaction described by the model.
The model is beneficial for CVE designers, as it
illustrates the available interaction forms. Thus, it is
possible to reduce the limitations and restrictions of
computer mediation by supporting more flexible and
natural interaction. Although the naturalness and
intuitiveness of face-to-face communication is hard to
achieve, the rich interaction model can direct designers to
additional and novel ways that could enhance the weak
areas of interaction.
6. Concluding remarks
The concept model of rich interaction forms illustrates
the various forms of communication, co-ordination and
collaboration in CVEs. A creative combination of
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interaction forms makes it possible to enhance the overall
interaction and further increases the communicative,
collaborative and constructive uses of the virtual
environments.
Although the mechanistic approach to interaction
modelling may be criticised, the interaction form oriented
analysis and design could be a solution that would support
the construction of more communicative and collaborative
systems. The top-down approaches to system design have,
to date, been unable to solve problems of computer-
mediated group activities. However, the proposed bottom-
up approach could be used as a design guideline that
would help the implementation of flexible-enough
interactions.
The interaction form model is significant for CVE
designers, as it illustrates the possible representations of,
for example, non-verbal communication in networked
settings. Thus, it is possible to reduce the limitations and
restrictions of computer mediation by enabling more
flexible and natural interaction. When designers know the
possible means of interaction, they can direct their effort
to the ones that best suit the application domain.
Furthermore, the basic set of interaction forms, being
given by the interaction model, enables the designers to
apply other design approaches, such as artistic selectivity,
to enrich the interaction.
7. References
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