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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Context Approach of Social Networks</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Patrick Brézillon</string-name>
          <email>Patrick.Brezillon@lip6.fr</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>LIP6 - University Pierre et Marie Curie Paris</institution>
          ,
          <country country="FR">France</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper proposes a context approach of social networks and virtual communities in the enterprise area. We point out that making context explicit it is possible to provide a global picture of the main aspects of social networks. A first result of this study is that the explicit consideration of contexts-especially shared contexts-could improve notably the collaborative-work processes in an enterprise. A second result shows the interest of simultaneously considering the paradigms of context and social network when IT is at the core of the enterprise. A third result is to point out that different types of context account for the flux of information between groups as well as inside each group. Finally, we point out that a virtual community can be considered as a contextualization of a social network.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>Facing rapid changes resulting from information and communication technologies
(ICT), many organizations enlarge their collaborative decision-making processes.
Decision makers work together but not necessarily at the same time and at the same
place. They are supported by communication systems like email or by Groupware
systems, which constitute a kind of electronic infrastructure superposed on
hierarchical organizations..</p>
      <p>Adam and Pomerol [1] presented the case study of XYZ Publications Ltd, a news
organization which publishes two newspapers: a national morning paper and a local
afternoon paper. The study was lead to understand the nature of the changes
undergone by the firm and analyze the group dimension of its decision making
processes. Brézillon et al. [2] present a groupware view on the case study.</p>
      <p>
        In this paper, we consider the role plays by context when the enterprise is
considered in term of social network. Organizations are fundamentally
informationprocessing structures [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. In this view, an organization is an information-processing
and communication system, structured to achieve a specific set of tasks, and
composed of actors that process information. Thus the enterprise is like an
"information space" with information fluxes between individuals. We do not discuss
here similarities and differences between social networks and virtual communities,
and with respect to communities in the real life1. An enterprise is considered such as a
social network, which constitutes a complex network of data, information and
1 This study enters the framework of a contract between France Telecom and LIP6.
knowledge, and several virtual communities appear at the different steps of the
information-management process corresponding to a series of specific focuses of
attention.
      </p>
      <p>There is a heterogeneity of contexts (personal context, board context, external
source contexts, etc.), which are at different granularities (the firm context, the board
context, the employee context, etc.). However, the key point is that the complex
information fluxes circulating inside the enterprise can be understood such as
information transfers between contexts at the different granularities.</p>
      <p>Hereafter, the paper is organized in the following way. Section 2 gives the
meaning given to the terms used in the paper, namely context, social network and
virtual community. Section 3 discusses different aspects of context considered as
important. Section 4 concludes by discussing some challenges that open new
perspectives.</p>
    </sec>
    <sec id="sec-2">
      <title>2. SOME TERMINOLOGICAL DEFINITIONS</title>
      <sec id="sec-2-1">
        <title>2.1 External Knowledge, Contextual Knowledge and Proceduralized Context</title>
        <p>
          Brézillon and Pomerol [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] consider three types of context, namely the external
knowledge, the contextual knowledge and the proceduralized context.
        </p>
        <p>As Figure 1 shows it, at a given focus of attention, one distinguishes the part of the
context that is relevant at this step and the part that is not relevant. The latter part is
called external knowledge. The former part is called contextual knowledge, and
obviously depends on the agent and the current focus of attention. Always for the
given focus, a part of the contextual knowledge is proceduralized to be used at the
focus of attention. We call it the proceduralized context. The proceduralized context
is the part of the contextual knowledge that is invoked, assembled, structured and
situated according to the given focus. Thus, the focus of attention and its associated
context are strongly intertwined.</p>
        <p>
          Contextual knowledge is more or less similar to what people generally have in
mind about the term 'context'. Contextual knowledge is personal to an agent and it has
no clear limit [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. Contextual knowledge is evoked by situations and events, and
loosely tied to a task or a goal. When the task becomes more precise, a large part of
this contextual knowledge can be proceduralized according to the current focus of
attention. Although the contextual knowledge exists in theory, it is actually implicit
and latent, and is not usable unless a goal (or an intention) appears as a focus. When
an unexpected event occurs, actor’s attention is focused on it and a part of the
contextual knowledge will be proceduralized accordingly in order to adapt the
decision-making process to this new event.
        </p>
        <p>
          The context is dynamic [
          <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
          ], and the dynamic dimension corresponds to a
movement between contextual knowledge and proceduralized context during the
evolution of the focus of attention: From one step to the next one, a piece of
contextual knowledge enters the proceduralized context or, conversely, the
proceduralized context goes back in the contextual knowledge and becomes a “chunk
of (contextual) knowledge” a la Schank [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] in the body of contextual knowledge and
this chunk of contextual knowledge can be recalled later as a whole in a new
proceduralized context. Thus, the more a person is experimented, the more the person
possesses available structured knowledge (i.e. chunks of contextual knowledge).
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2 Definition of a Social Network</title>
        <p>
          A social network is the connection of people by a computer network [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], and Internet
will be the larger social network that we will consider in this paper. The main point is
that a social network is composed of actors and ties between them (e.g. see [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]). Ties
in a social network are numerous and of different natures: familial ties, lifelong friend
ties, marital ties, business partner ties, that are important for people to obtain the
fundamentals of identity, affection, emotional and material support [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ], i.e. the
recognition of their existence by others. However, the commitment of individuals is
superficial, limited to the reasons of the local interaction [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]. As a consequence, ties
in a social network are "socially-oriented" like in the real life (weak ties), trust does
not play an important role, and individuals generally belong to several social
networks.
        </p>
        <p>A discriminating factor can allow to contrast the social network with respect to its
environment. Thus, a discriminating factor differentiates individuals in a social
network and individuals in its environment. For example, registration to a mailing list
on a specific topic is to enter a social network where you will find (or may provide)
information on the topic, but ties with other members do not matter essentially or
would suppose the development of specific interaction inside some groups of the
social network. Individuals in the social network are called actors for differentiating
them from individuals in the environment of the social network.</p>
        <p>
          The multiplicity of ties between actors implies that the emphasis on one type of
social network or another one will depend on the viewpoint chosen on the social
network. Thus, the main characteristics of a social network are a flexible structure, a
lack of hierarchy, and weak importance of the emotional dimension [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]. From an
information point of view, any actor in a social network is a receiver/emitter of
information, but generally not an information transformer.
        </p>
        <p>There exists many discriminating factors and as many social networks as
discriminating factors. A discriminating factor does not imply strong ties among
actors because a discriminating factor is neither a goal shared by actors of the social
network nor a common focus of attention of the actors. For example, a discriminating
factor is "Living in France" and all actors in this social network share some common
interests on, say, French cooking and wine, but will not act collectively in the same
direction for that purpose. Belonging to a social network does not suppose that actors
have an active role in it.</p>
      </sec>
      <sec id="sec-2-3">
        <title>2.3 Definition of a Virtual Community</title>
        <p>
          The man difference, which is identified in the literature between a virtual community
and a social network, concerns computer-mediated means. Divisibility of social
networks into cooperative subgroups (virtual communities) that do not cooperate with
each other is an old idea [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ]. The key point is the distinction between the
computermediated communication concerning either individuals (e-mail, chat, blogs, etc.) or
collaborative work (writing, designing, etc.). Clearly the collaborative decision
making is ascribed in this second realm, and then the “focus-oriented” aspect is more
important than the “computer-mediated” aspect.
        </p>
        <p>The Information and Communication Technology gives an electronic
infrastructure on the organization, which is supposed to reinforce the coherence of the
virtual community. However, there is more than a difference of infrastructure between
a social network and a virtual community. A virtual community is a part of a social
network to realize a collaborative work in order to satisfy a given focus of attention.</p>
        <p>
          A virtual community is a group of actors who have regular contact with one
another in cyberspace, with shared interests, problems or ideas (i.e. a shared focus of
attention), independently of space and time. A main characteristic of virtual
communities is that they are homogeneous and organized networks of individuals
with similar attitudes and life-styles [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ], and they are intentional formations [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ].
This cohesiveness of the virtual community with respect to the rest of the social
network is given by the common focus of attention of all the actors.
        </p>
        <p>
          The focus of attention gives a structure on the virtual community by defining an
organization of roles on the virtual community and a coordination of the collaborative
work of actors. The focus of attention acts like an internal engine to impulse the
virtual community. Actors have then a strong motivation in the realization of the
focus and each actor assumes an active role to satisfy this process. Thus, actors in a
virtual community are “socially interdependent” [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ], not uniquely "socially-oriented"
like in the social network. A parallel in the domain of decision making, would allow
to say that one may observe only a diluted decision making in a social network and a
collaborative decision making in a virtual community.
        </p>
        <p>
          In a virtual community, the focus of attention affects actors as a glue force that
influence ties between actors (directly connected to the focus of attention and the
related roles that actors have to play and the corresponding tasks to accomplish [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]),
although the virtual community stays primarily a social network and keeps all its
characteristics in a context that is strongly related to the focus of attention of the
virtual community.
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. SOME ASPECTS OF CONTEXT</title>
      <sec id="sec-3-1">
        <title>3.1 Lessons learned in a case study</title>
        <p>We now consider again the case study introduced at the beginning of the paper and
presented in [1]. It is important to acquire the information and its context for a correct
understanding of the information. Information and its context must be considered
jointly because the information takes a meaning within its context, and, conversely,
this context is identified with respect to the information.</p>
        <p>
          Actors can share contextual elements of their individual contexts to build
collaboratively a proceduralized context for the solution in the interaction context.
Sharing elements does not mean to develop an identical view of the solution for all
actors, but to make compatible actors' views on the solution [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ].
        </p>
        <p>An enterprise, such as the XYZ firm, is assimilated to a social network, the
discriminating factor being to belong or not to the XYZ firm. However, the frontier
between the social network (i.e. the XYZ firm) and its environment is porous,
unpredictable events occurring generally outside the XYZ firm. An external event
triggers an information management process in several successive steps. At each step
of this process there is a particular focus with its context and thus a working group is
organized like a virtual community for addressing this particular focus.</p>
        <p>Although we speak about the context of the current focus, there are different
contexts that are associated with elements such as the social network, the virtual
communities, the actors, the enterprise, etc. These contexts can be organized in a
hierarchy based on the granularity of the contexts such as presented in Figure 2. In the
example of the XYZ firm, the information process management relies on such a
context hierarchy because each context is associated with a particular focus.</p>
        <p>Another lessons learned from the case study is at the level of each context. Let’s
consider the context of a a working group. Its context (as for other contexts) presents
two aspects depending on an internal or external viewpoint. From an internal
viewpoint, this “group context” contains contextual knowledge such as the general
policies, roles and tasks to accomplish, rules, constraints, objectives. This contextual
knowledge is proceduralized for the given focus of attention in strategies applicable
by the actors (within their "individual contexts") participating in the working group.
From an external viewpoint, the working group interacts with other entities and thus
the group context can be considered as an "individual context" in a larger group (e.g.
a market, an European project, etc.) in which proceduralized contexts are built from
contextual knowledge of the larger group.</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2 Context Granularity</title>
        <p>As said previously, information circulates across contexts. At a general level, we
distinguish the group context, the individual contexts of the actors at an intermediate
level, and at the more specific level, the context of the focus of attention that
corresponds to the interaction context in which actors are working collaboratively.
Figure 2 illustrates the situation for the XYZ firm where the focus of attention
corresponds to the project realization (and associated with the project context).</p>
        <p>According to our definition of context, the contextual knowledge at one level is
transformed in a proceduralized context at the more specific level. For example,
contextual information of the group context could be "find a compromise between a
relevant information for the readers of the newspaper and the notoriety of the
sponsors of the newspaper." This contextual knowledge in the group context will be
interpreted at the individual contexts of the actors writing the article in a
proceduralized context to give the information, say, without links with the sponsors.</p>
        <p>With respect to the notion of social network, context intervenes as intertwined
mainly with the virtual community, because the proceduralized context is built in a
collaborative way by the actors of the virtual community that share a common focus
of attention. The focus of attention leads to the construction of a proceduralized
context at each step of its evolution. The saving of the proceduralized context in each
actor’s context implies that there is a shared part of the individual contexts developed
progressively among actors. The shared context is developed along actors' interaction
in the virtual community during the construction of the proceduralized context. As a
consequence, actors develop ties during this construction of the proceduralized
context.</p>
        <p>The presentation of a virtual community through its focus of attention and the
related context, the proceduralized context that is built, and the ties evolution that
results, leads to speak of “contextualization of a social network” rather than virtual
community.</p>
      </sec>
      <sec id="sec-3-3">
        <title>3.3 Interaction Context and Proceduralized-Context Construction</title>
        <p>When a unexpected event occurs, a focus of attention appears in a given context. Both
focus and its context have to be considered jointly. Focus and context could concern a
group of actors in a social network that have a same concern for the focus and are
sensible to its context, and thus will interpret the focus with respect to this context. It
appears an organization of tasks to accomplish and of roles that actors of the group
have to play. The actor group becomes assembled, organized and structured like a
virtual community and thus will be able to realize a real collaborative work.</p>
        <p>
          The transformation of contextual knowledge in a proceduralized context supposes
a process of communication between different levels. Figure 3 represents how the
proceduralized context (PC) is built from contextual knowledge (CK and EK
representing the external knowledge) in individual contexts of two (or more) actors
during their interaction about the given focus of attention. The interaction context
contains the pieces of contextual knowledge put by each actor (i.e. from their
individual contexts) in the interaction context to make them visible and shared with
other actors, and finally assembled and structured jointly by all the actors during their
interaction to constitute the proceduralized context needs at the given focus of
attention. Thus, the proceduralized context is the result of a co-construction by the
actors of a virtual community. Once the proceduralized context has been exploited at
the current focus of attention, it becomes a piece of actors' shared contextual
knowledge. A discussion on this aspect of context can be found in [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ].
        </p>
        <p>Ties are managed at different levels between the actors of the virtual community
during this proceduralized-context construction until its final movement into their
shared contextual knowledge.</p>
      </sec>
      <sec id="sec-3-4">
        <title>3.4 A Context-based view of Social Networks</title>
        <p>From previous sections, virtual communities are assimilated to contextualizations of a
social network, with (1) contextualization resulting of the focus-dependent
reinforcement of ties among groups of actors and (2) ties reinforcement being
developed during the proceduralized-context construction.</p>
        <p>This leads to a parallel between both views on context and on social network.
Figure 4 presents a situation for a social network and virtual community (virtual
communities are represented distinctly from the original social network only for
making more readable the comparison) similar to the situation describes in Figure 2
for the different types of context. The more the granularity is high, the more the entity
is organized and structured. Thus, a proceduralized context (respectively a virtual
community) has a higher organization than a body of contextual knowledge
(respectively the social network).</p>
        <p>
          Another parallel between the pairs {contextual knowledge, proceduralized
context} and {social network, virtual community} is the following. In both cases,
what is unstructured elements (contextual knowledge and actors) becomes at the
upper level a chunk of knowledge (a proceduralized context) and a "chunk of actors" (
a virtual community).
4. CONCLUSION AND PERSPECTIVES
Until now studies on collaborative work, context, social network, virtual community
have been lead separately with any cross-references. In this paper we show that
context plays a central role in order to, in the one hand, give a global and coherent
view on social network and virtual community, and, in the other hand, replace
collaborative work in a new framework providing a new insight on interrelationships
between participants (all coming from a same social network): creating ties being
equivalent to build a proceduralized context and the development of a large shared
context. This new insight on collaborative work comes from the choice to consider an
enterprise as a structure of information fluxes. This leads to a problem of knowledge
management, in which the important point is the management of all the transitions
between all the different states of the knowledge such as tacit, implicit, individual,
collective, etc. [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ]. Putting all together, the integration of knowledge management,
context management and context management seems to be a new challenge in
collaborative work.
        </p>
        <p>
          A virtual community has a life cycle wit a birth, a life and an end, which is shorter
than the life cycle of the social network. Maybe the most interesting difference
between a social network and a virtual community is that the virtual community can
be compared to a dissipative structure as discussed some times ago in the living
system area [
          <xref ref-type="bibr" rid="ref21">21</xref>
          ], i.e. a structure that maintains an organization using the flux of
energy (the information) that crosses it.
        </p>
        <p>
          We introduce the notion of "chunk of actors" to lead a parallel with the notion of
chunk of knowledge a la Schank [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] and introduces a dynamic dimension to
collaborative work apparently not considered explicitly before. Moreover, context can
be related to virtual community because the latter results of a process of
contextualization in a social network corresponding to the expression “chunk of
actors. “
        </p>
        <p>
          Even in the unique domain of social network and virtual community, the view
presented in this paper is a challenge. First, the view of a virtual community as a
contextualization of a social network to address a given focus of attention is not usual
in the literature. This is shown in another domain [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] with practices representing
contextualizations of the procedures established by the enterprise in order to address
the specificity of the contextual cues of the situation (the focus of attention). Second,
the evolution of a focus of attention is described as a series of contextualizations of a
social network for dealing with different steps of the global focus of attention. Three,
a large project (e.g. an European project) can lead simultaneously to the birth of
several virtual communities acting in parallel on parts of the problem to solve (e.g. the
work packages).
        </p>
        <p>Acknowledgments:
Grants are provided by a contract with France Telecom R &amp;D. We also thank Cécile
Bothorel from France Telecom and Emilie Ogez, Ph.D. student at the University Paris
6 (on grants from France Telecom) for the discussions around the notion of social
network and virtual community.</p>
      </sec>
    </sec>
    <sec id="sec-4">
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