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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Social Information Flow Graph: Design and Prototypical Implementation</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Thomas Reschenhofer</string-name>
          <email>reschenh@in.tum.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Patrick Burgin</string-name>
          <email>patrick.buergin@tum.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Florian Matthes</string-name>
          <email>matthes@in.tum.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Technical University of Munich</institution>
          ,
          <addr-line>Munich</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <fpage>137</fpage>
      <lpage>144</lpage>
      <abstract>
        <p>Companies are increasingly turning to Enterprise 2.0 technologies to harness collective intelligence for information management and analysis. In this context, social network analysis (SNA) provides insights into which knowledge workers interact with which information assets and thus improves cooperation among them. However, current approaches to SNA disregard semantic relationships between the information assets or the relevance of the applicability of SNA by end-users. In the paper at hand we address this issue by proposing the social information ow graph (SIFG) as a tool for end-user-oriented SNA. In this sense, the SIFG provides a holistic and social perspective on relationships between individuals and information assets within an Enterprise 2.0 environment. We showcase its technical applicability by a prototypical implementation. By conducting case studies in three di erent application domains, we show that the SIFG and its explorability enable novel opportunities and use cases for end-user-oriented SNA.</p>
      </abstract>
      <kwd-group>
        <kwd>Information Flow Graph</kwd>
        <kwd>Social Network Analysis</kwd>
        <kwd>Enterprise 2</kwd>
        <kwd>0</kwd>
        <kwd>Information Visualization</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Today's enterprises are facing not only the challenge of managing an
increasing amount of digital information, but also to do this in an e cient way [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
To tackle this challenge, enterprises apply collaborative technology to foster the
contribution of multiple knowledge workers [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] in order to harness collective
intelligence. By the collaborative creation and management of information and
services, knowledge workers implicitly form a social network. Analyzing those
interactions can reveal interesting knowledge (e.g., communication patterns) about
an organization's social structure and dynamics [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. However, making this
knowledge accessible to the organization's users and thus to enable end-user-oriented
social network analysis (SNA) is a big challenge [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>On another note, data has to be processed and presented according to the
speci c needs of knowledge workers in order to support decision making based
on it. Knowledge workers often have di erent requirements regarding the
representation of the same information, e.g., they might be interested in di erent
levels of detail. End-user-oriented business intelligence (BI) tools enable them
to process and represent a given information according to their needs without
having to rely on IT specialists. Thereby, knowledge workers are able to de ne
custom data transformations and tailored data visualizations. However, if
multiple knowledge workers de ne data transformations and visualizations based
on the same information, it is challenging to keep track of which information is
transformed and visualized in which way.</p>
      <p>To address this issue, information ow diagrams make the information ow
from its source through its transformations to visualizations transparent. While
in a non-collaborative setting, individual knowledge workers de ne how
information is processed and represented based on their individual needs and
independently from co-workers, in a collaborative environment users not only cooperate
in managing of information, but also in its processing and presentation, e.g.,
by sharing transformations or visualizations, or by de ning them jointly. This
inevitably leads to a more complex information ow structure, which makes it
more di cult for users to understand connections between information assets.</p>
      <p>In the present paper, we propose a concept for the utilization of
information ow graphs for end-user-oriented SNA. In this sense, a social information
ow graph (SIFG) not only visualizes how the information ows through a
software system, but also which users are interacting with it. Therefore, it provides
a social and holistic perspective on information assets and their relations. We
also address the challenge of making the SIFG explorable by end-users to
ensure its practical applicability. Finally, we identify concrete concerns in di erent
application domains which can be addressed by a SIFG.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Conceptual Design of a Social Information Flow Graph</title>
      <p>
        As described by Chi and Riedl's [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] Information Visualization Data State
Reference Model, data is transformed to analytical abstractions, and subsequently
bound to visualization abstractions. These visualization abstractions are the
basis for the nal view which is consumable by users. In order to keep the SIFG
model simple and applicable, we subsume Chi and Riedl's concepts of Data and
Analytical Abstraction under Data, and their notion of Visualization Abstraction
and View under View. Furthermore, we explicitly model Chi and Riedl's Data
Transformation and Visualization Transformation, while we name the latter one
Data Binding in accordance to the model-based approach of Hauder et al. [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. A
Data Transformation derives data from potentially multiple data elements, while
a Data Binding connects potentially multiple data elements to visualizations.
      </p>
      <p>
        The concepts Data, View, and Transformation are considered as
InformationAsset s as de ned by Khatri and Brown [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], i.e., they are documented facts
with a potential value for a stakeholder. Therefore, we introduce a corresponding
class as super type for Data, View, and Transformation. Each InformationAsset
has MetaData representing descriptive information about its structure, context,
or semantics [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. This also includes di erent kinds of relations between
InformationAsset s and User s, e.g., who is responsible for a certain InformationAsset [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ],
Transformation
      </p>
      <p>*
DataTransformation</p>
      <p>InformationAsset</p>
      <p>Data</p>
      <p>*
transforms to ►
DataBinding</p>
      <p>has ►
View</p>
      <p>*
visualized in ►
*</p>
      <p>MetaData
Ownership</p>
      <p>*
◄ has</p>
      <p>1
User
*</p>
      <p>Usage
*</p>
      <p>
        …
◄ captures
who uses it [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], and who creates it [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. The concrete meta data types depend
on the actual use case, and can be added to the model as indicated in Figure 1.
      </p>
      <p>
        The SIFG enables the derivation of new social relationships by considering
interactions with di erent information assets which are connected to each other
through a chain of transformations. For example, the owner of a particular data
object can be associated with a user consuming the same data object through a
corresponding visualization. As a consequence, the proposed model opens new
opportunities for improving organizational social network analysis [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>A Prototypical Implementation</title>
      <p>
        The prototype is built upon a model-based Enterprise 2.0 platform called
Hybrid Wikis [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. In this platform, the initially unstructured data entities can be
structured incrementally and collaboratively by enabling end-users to
dynamically de ne a data model consisting of entity types, attributes, and relationships.
On the top of this data modeling concept, the Hybrid Wiki platform integrates
the model-based expression language (MxL) for the user-driven de nition of
queries [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] as well as con gurable dashboards consisting of potentially
multiple visualizations. MxL's static type-safety enables the automatic detection ofo
semantic dependencies between expressions and elements they are referring to.
Those dependencies are the input for the automatic generation of an information
ow graph. For example, a query de ned by an MxL expression and referring to
a data entity implies a dependency from the query to the data entity, while the
information ows into the opposite direction.
      </p>
      <p>Regarding the conceptual model as described in the previous section, the
Hybrid Wiki entities as Data, dashboards and visualizations as View s, and MxL
expressions as both DataTransformations and DataBinding s form the system's
InformationAsset s. Each of those information assets is de nable and editable by
users, and possesses a speci c set of meta data attributes. For example, each
information asset has a version history capturing its temporal evolution, or
authorization rules controlling the access to it in a collaborative environment. These
meta data attributes|and particularly the user-related meta information|can
be used by the prototype to enrich the aforementioned information ow graph
and to generate the SIFG. Therefore, the prototype represents a full
implementation of the conceptual model as presented in Section 2.</p>
      <p>In the following, we illustrate the prototype by implementing a simple sales
scenario which involves customers, orders, products, and categories. A customer's
turnover is de ned as derived attribute, i.e., the value is calculated automatically
according to a given computation prescription. Derived attributes represent data
transformations as de ned in Section 2. In the prototype, a customer's turnover
can be de ned by the MxL expression Orders.sum(Product.Price). Based on
this, a query computing the total turnover of all customers can be de ned as
nd Customer.sum(Turnover). The nd construct retrieves all customers. Based
on this collection as well as a lambda expression referring to the turnover of
each customer, the sum function computes the total turnover. In this example,
there is a semantic dependency from the query to the derived attribute turnover,
which in turn depends on the order's product and the respective product's price.
Therefore, there is an information ow from the product's price through the
derived attribute turnover to the total turnover query.</p>
      <p>Figure 2 shows a dashboard illustrating, e.g., the temporal evolution of the
daily turnover within a line chart, or a cluster map organizing the products
within their categories. Each visualization is con gured separately, i.e., for each
visualization users have to de ne a corresponding data binding by using MxL
expressions. Based on the data model, data transformations (e.g., derived
attributes), as well as visualizations and their data bindings, the prototype
automatically generates the SIFG in real-time. As shown in Figure 3, the information
ow's starting points are the Hybrid Wiki system's entity types (e.g., Order and
Customer ) which are organized in so-called workspaces (the dark-blue boxes on
the left, e.g., Northwind ). The internal structure of the types (e.g., attributes
and derived attribute) is not shown, since this would add to much complexity
to the view. Visualizations are illustrated by respective icons and composed to
dashboards (the red boxes on the right, e.g., Northwind ). In between, there are
functions representing generic data transformations, e.g., turnoverPerDay.</p>
      <p>
        The prototype provides UI features inspired by Heer and Boyd [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] to improve
the usability of the SIFG for end-users. When clicking on a node, the prototype
shows the meta information for the respective information asset on the
righthand side of the graph view. For example, in Figure 4 the meta information for a
visualization is shown, including user-related meta information like its ownership
and version history. Depending on the actual use case, the set of displayed meta
information can be extended accordingly, e.g., by information on the usage of the
selected information asset. Furthermore, clicking on a particular node highlights
all (transitive) predecessors as well as (transitive) successors. In this way, a user
can identify all information sources which the selected node depends on, and all
visualizations for which the selected node is an input. This enables users, e.g.,
to nd the contact person for the input of a particular visualization.
      </p>
      <p>To abstract and hide certain parts of the graph view, users can collapse
workspaces or dashboards. This can reduce the complexity of the graph view
and increase its understandability. As shown in Figure 5, collapsing a dashboard
hides all its visualizations. All information ows which initially targeted those
visualizations are now heading to the dashboard instead.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Case Study</title>
      <p>We conducted a case study including three cases in di erent application domains
and di erent German companies. In each of those cases, knowledge workers
already use a BI tool for analyzing and visualizing domain-speci c data in an
end-user-driven way. The study shows concrete concerns those knowledge
workers can address when using the SIFG prototype. To this end, we asked them
for their opinion on the SIFG and for related concerns which they face in their
daily work, and which could be resolved by our approach. The rst interviewee
is an enterprise architect who currently manages the internal architecture of a
German IT services provider (5,000 - 10,000 employees), while the second one is
an IT infrastructure manager of a subsidiary of a German investment company
(10,001+ employees). The third interviewee is a data quality manager of a
German company (10,001+ employees). For the sake of discussion, we exemplarily
implemented a representative dashboard for each of the observed cases.</p>
      <p>The interviews revealed the following concerns which are addressable by the
demonstrated prototype in particular, and the SIFG in general:
Usage Analysis: As stated by the interviewees, "the collection of data induces
the highest cost in our daily business". By using the SIFG, data model
maintenance process can be optimized by stopping to maintain unused data.
Stakeholder Identi cation: The interviewees stated that the SIFG could be
used to identify stakeholders which are related to certain information assets,
enabling them to proactively contact the users which express their interest
in a given dashboard.</p>
      <p>Impact Analysis: According to the interviewees, users tend to avoid changes
of certain information assets, since they are afraid to "break something".
Faced with the SIFG, the interviewees expressed that "this would certainly
help to make the models and relations more transparent".</p>
      <p>Support for Data Provenance: As stated by the interviewee, sharing data
among colleagues is "part of the daily business". Thus it is "interesting to
know what the story behind a given information asset is", raising questions
such as "Where does the data come from? Who worked on it? When was the
last change and by whom?". Providing an environment to visually explore
the SIFG may reduce the "signi cant operative cost" induced by struggles
when identifying co-workers that faced similar problems in the past.
Addressing Compliance Demands: Driven by compliance demands, certain
organizations (particularly in the nancial services domain) have to be able
to reveal the full calculation process behind a given measure or visualization.</p>
      <p>The SIFG may help to meet these demands.</p>
      <p>Support for Data Consolidation: The interviewees stated that the SIFG is
helpful to initiate consolidations of dashboards and views based on
overlapping information, i.e., information which is visualized in di erent dashboards.</p>
    </sec>
    <sec id="sec-5">
      <title>Related Work</title>
      <p>
        Huner et al. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] discuss requirements of a collaborative MDM repository, and
highlight the relevance of collaboration for e ective MDM. However, they do
not elaborate on how the analysis of a information ow graph or social networks
could improve the repository's support for MDM processes. For example, they
propose a process for the maintenance of business meta data including activities
like "Identify responsibility", which can be supported by the SIFG.
      </p>
      <p>
        On another note, Dinter et al. [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] investigate the opportunities of MDM for
di erent kinds of stakeholders. Thereby, they identify bene ts like "Impact
analysis" and "Data lineage/provenance", which match with the identi ed concerns
as described in Section 4. Their study shows that the potential bene t of
particularly those three mentioned bene ts is exceptionally high|especially for BI
users|while the level of actual implementation is still low.
      </p>
      <p>
        Hermans et al. [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] discuss data ow diagrams for spreadsheets. They present
a tool for automatically creating them based on cell references. By evaluating
the use of data ow diagrams for the analysis of spreadsheets by conducting a
survey, they found out that a holistic perspective on the information ow within
a spreadsheet is helpful for 80 % of survey participants. However, they also state
that the level of detail and understandability of data ow diagrams has to be
well-balanced in order to provide helpful insights into the spreadsheet dynamics.
      </p>
      <p>
        In addition to researchers, software vendors also try to utilize the
dependencies and relationships between both information assets and users in order to
expose new knowledge [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. For example, Microsoft's O ce Delve allows users
to analyze information and activities within the O ce 365 Suite.
6
      </p>
    </sec>
    <sec id="sec-6">
      <title>Conclusion</title>
      <p>This work presents a concept and a prototypical implementation for a SIFG,
which not only makes semantic dependencies between information assets
visible and explorable for end-users, but also integrates relations to users of the
system. In this way, the SIFG supports the identi cation of new social
relationships between users, and thus fosters collaboration among knowledge workers.
Its conceptual model as described in Section 2, the UI features described in
Section 3, and the interviews as described in Section 4 represent the answers to the
research questions raised in the present paper's introduction.</p>
      <p>
        With respect to the validity of the exploratory case study, three cases form
a small foundation for both an evaluation of the SIFG as well as the identi
cation of concrete concerns addressable by it. However, the interviews represent
a preliminary study for a more extensive study on concerns in one particular
domain. While the interviewees agreed on the high potential of the SIFG, they
also outlined ethical and privacy issues [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. All interviewees mentioned that their
company's work councils "would have worries if users can see all the activities of
their co-workers". However, the interviewees also stated that a proper balance
between transparency and privacy would ensure a reasonable practicability while
also taking into account ethical and legal concerns.
      </p>
      <p>Based on the results of the paper in hand, our future research activities will
focus on the improvement of the SIFG with respect to its application in a speci c
domain, namely EAM. Therefore, we aim for an extension of this concept and the
prototype in order to address the speci c concerns as identi ed in the interview
with an enterprise architect. Furthermore, we plan to do an extensive evaluation
within a research community including more than 20 enterprises.</p>
    </sec>
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