=Paper=
{{Paper
|id=Vol-273/paper-12
|storemode=property
|title=OntoWiki: A Tool for Social, Semantic Collaboration
|pdfUrl=https://ceur-ws.org/Vol-273/paper_91.pdf
|volume=Vol-273
|dblpUrl=https://dblp.org/rec/conf/www/AuerDLR07
}}
==OntoWiki: A Tool for Social, Semantic Collaboration==
https://ceur-ws.org/Vol-273/paper_91.pdf
OntoWiki
A Tool for Social, Semantic Collaboration
Sören Auer Sebastian Dietzold
University of Pennsylvania University of Leipzig
Department of Computer and Information Department of Computer Science
Science P.O.Box 100920
Philadelphia, PA 19104, USA D-04009 Leipzig, Germany
auer@seas.upenn.edu dietzold@informatik.uni-leipzig.de
Jens Lehmann Thomas Riechert
University of Leipzig University of Leipzig
Department of Computer Science Department of Computer Science
P.O.Box 100920 P.O.Box 100920
D-04009 Leipzig, Germany D-04009 Leipzig, Germany
lehmann@informatik.uni-leipzig.de riechert@informatik.uni-leipzig.de
ABSTRACT 1. INTRODUCTIONS
We present OntoWiki, a tool providing support for agile, We present a tool supporting agile Knowledge Engineer-
distributed knowledge engineering scenarios. OntoWiki fa- ing in a pure Web environment. It is called OntoWiki since
cilitates the visual presentation of a knowledge base as an it is close in the spirit to existing Wiki systems. Techno-
information map, with different views on instance data. It logically however, the OntoWiki design is independent and
enables intuitive authoring of semantic content, with an in- complementary to conventional Wiki technologies. As such,
line editing mode for editing RDF content, similar to WYSI- the OntoWiki approach differs from recently emerged strate-
WYG for text documents. It fosters social collaboration as- gies to integrate Wiki systems and the Semantic Web (cf. [5,
pects by keeping track of changes, allowing comments and 7]). In these works it is proposed to integrate RDF triples
discussion on every single part of a knowledge base, enabling into Wiki texts in a special syntax. It is a straightforward
to rate and measure the popularity of content and honor- combination of existing Wiki systems and the Semantic Web
ing the activity of users. OntoWiki enhances the browsing knowledge representation paradigms. The OntoWiki strat-
and retrieval by offering semantic enhanced search strate- egy presented in this paper, on the contrary, does not try
gies. All these techniques are applied with the ultimate goal to mix text editing with knowledge engineering, instead it
of decreasing the entrance barrier for projects and domain applies the Wiki paradigm of “making it easy to correct
experts to collaborate using semantic technologies. In the mistakes, rather than making it hard to make them”[6] to
spirit of the Web 2.0 OntoWiki implements an ”architec- collaborative knowledge engineering. The main goal of the
ture of participation” that allows users to add value to the OntoWiki approach thus is to rapidly simplify the presenta-
application as they use it. It is available as open-source tion and acquisition of instance data from and for end users.
software and a demonstration platform can be accessed at This is achieved by regarding knowledge bases as ”informa-
http://3ba.se. tion maps”. Each node at the information map is repre-
sented visually and intuitively for end users in a generic but
configurable way and interlinked to related digital resources.
Categories and Subject Descriptors To stress the generic character of OntoWiki, the figures
H.4.m [Information Systems Applications]: Miscella- in this paper show screenshots of the OntoWiki prototype
neous; with a knowledge base collaboratively developed1 and con-
K.4.3 [Computers and Society]: Organizational Impacts— taining information about scientific conferences, as well as
Computer-supported collaborative work ; another publicly available knowledge base2 containing infor-
H.2.8.f [Database Management]: Database Applications— mation about research projects, people and publications at
Knowledge management applications a research institute.
2. SYSTEM AND FEATURE DESCRIPTION
Keywords
Semantic Wiki, Social Software, Semantic Collaboration 2.1 Visual Representation
Web pages in OntoWiki, representing nodes in the infor-
mation map, are divided into three parts: a left sidebar, a
main content section and a right sidebar. The left sidebar
Copyright is held by the author/owner(s). 1
WWW2007, May 8–12, 2007, Banff, Canada. at http://3ba.se
2
. http://www.aifb.uni-karlsruhe.de/viewAIFB OWL.owl
Figure 1: List view (left) and view of an individual instance with expanded inline reference view (right).
offers the selection of content to display in the main content selected calendar items into a desktop calender application.
section. Selection opportunities include the set of available
knowledge bases, a class hierarchy browser and a full-text 2.2 Collaborative Authoring
search. Once a selection is made, the main content section For human users it is important that the statements of a
will arrange matching content in a list view linking to in- knowledge base are presented on the user interface in a way
dividual views for individual instances (cf. Figure 1). The which facilitates the efficient reception of this information.
right sidebar offers tools and complementary information For instance, if it is clear that a single object is described,
specific to the selected content. it will be displayed only once on the OntoWiki user inter-
List views allow to view a selection of several instances face, even though all the statements describing the concept
in a combined view. The selection of instances to display contain the concept URI as subject. Furthermore, if a prop-
can be either based on class membership or on the result of erty (e.g. referencing publications) occurs multiple times
a selection by facet or full-text search. OntoWiki identifies those statements are grouped together and the label of the
those properties used in conjunction with the instances of property is displayed only once.
the selection. The display of the corresponding property To enable users to rapidly edit or add statements as soon
values for each instance can be switched on, thus resulting as they notice mistakes or missing information, OntoWiki
in a tabular view. Furthermore, each individual instance features an inline editing mode. This means that all infor-
displayed is linked to an individual view of that instance. mation originating from statements presented on the On-
Individual views combine all the properties attached to a toWiki user interface is equipped with a small edit button
particular instance. Property values pointing to other in- as well as an add button. After clicking one of those buttons
dividuals are rendered as HTML links in the corresponding a resource editor is loaded and the corresponding statement
individual view. Alternatively, to get information about the can be easily edited – or similar content (i.e. a statement
referenced individual without having to load the complete with the same subject and predicate) can be added. This
individual view, it is possible to expand a short summary strategy can be seen as an analogy to the WYSIWYG (What
(loaded per AJAX) right where the reference is shown. The You See Is What You Get) editing strategy for text editing,
right sidebar provides additionally information about sim- since information can be edited in the same environment as
ilar instances (of the same type) and incoming links (i.e. it is presented to users.
references from other instances). Conventional Web technologies do not support large data
sets to be handled at the client (browser) side, but this is
The OntoWiki prototype facilitates different views on in-
usually needed when working with large knowledge bases.
stance data. The following views are currently implemented:
To overcome this limitation, reloading of web pages be-
Map View: If the selected data (either a single instance comes necessary. This approach is time consuming and re-
or a list of instances) contains property values representing quires multiple user interactions. Recently, with the de-
geographical information (i.e. longitude and latitude coor- ployment of more sophisticated Web browsers, supporting
dinates or a relation to a resource with coordinates), a map modern JavaScript and XML technologies, mixed server and
view provides information about the geographical location client side web applications became possible. These were re-
of the selected data (cf. Figure 2). cently named AJAX (Asynchronous JavaScript and XML)
Calendar View: Instances having property values with the and early adopters such as Google-Maps3 or Flickr4 make
associated datatype xsd:date can be displayed in a calendar
3
view (cf. Figure 2). The sidebar offers a link to export http://maps.google.com
4
calendar items in iCal format, which enables to import the http://www.flickr.com
Figure 2: Map view (left) and calendar view (right) of instance data.
extensive use of them. OntoWiki uses the AJAX technology 2.3 Enabling Social Collaboration
to interactively propose already defined concepts while the A major aim of OntoWiki is to foster and employ social
user types in new information, which he wants to add to the interactions for the development of knowledge bases.
knowledge base. To realize this interactive search, all URI This eases the structured exchange of meta-information
references and literals are indexed for full-text searches in about the knowledge base drastically and promotes collab-
the statement repository. oration scenarios where face-to-face communication is hard.
For convenient editing of differently typed literal data, Furthermore, making means of social interactions as easy as
the OntoWiki system provides a library of reusable user in- possible contributes in creating an ”architecture of partici-
terface components for data editing, called widgets. The pation” that allows users to add value to the system as they
following widgets are currently provided by the prototypi- use it. Social collaboration within OntoWiki is in particular
cal OntoWiki implementation: Statements allowing to edit supported by:
subjects, predicates, and objects, Nodes to edit literals or
Change tracking: All changes applied to a knowledge base
resources, Resources to select and search from/for existing
are tracked. OntoWiki enables the review of changes on dif-
resources, Literals to display literal data in conjunction with
ferent levels of detail (see also [2]) and optionally restricted
data type or language identifier, File to upload files to On-
to a specific context, such as changes on a specific instance,
toWiki, and specific widgets for literal data types, e.g. a
changes on instances of a class, or changes made by a distinct
calendar for dates.
user. In addition to present such change sets on the Web,
All widgets can be configured. The OntoWiki system al-
users can subscribe to get information about the most recent
lows to define and attach certain sets of configurations to a
changes on objects of their interest by email or RSS/Atom
specific widget.
feeds.
Editable views are combinations of widgets to edit a spe-
cific view on the knowledge base in one single step. The Commenting: All statements presented to the user by the
OntoWiki system provides the following types of editable OntoWiki system may be annotated, commented, and their
views: usefulness can be rated. This enables community driven
discussions, for example about the validity of certain state-
• Metadata: Comments, labels, and annotations (such as ments.
versioning and compatibility information) which can
Rating: OntoWiki allows to rate instances. Users have to
be attached to arbitrary resources are combined in a
be registered and logged in to participate in order to avoid
metadata view.
duplicate ratings by the same user. A user may change his
• Instances: An instance view combines all properties rating for a certain instance. Special annotation properties
attached to the instance’s class or one of the super- allow the creation of rating categories with respect to a cer-
classes. For large knowledge bases, this might include a tain class. Instances of the class can then be rated according
large amount of properties. The OntoWiki system thus to these categories, thus allowing for example the rating of
allows to restrict the view to such properties which are instances of a class publication according to categories orig-
really used in conjunction with other instances of the inality, quality and presentation.
same class. On the basis of range definitions for the Popularity: All accesses to the knowledge base are logged
property, OntoWiki selects appropriate editing wid- thus allowing to arrange views on the content based on pop-
gets. Additional properties can be added on-the-fly. ularity. As with ratings or user activity, the popularity of
• Views: The earlier described inline-editing technique content can be measured with respect to a certain knowl-
allows to edit arbitrary views. The columns of list edge base or fragment of it (e.g. popularity with respect to
views arranging many instances in a tabular way, for class membership). This enables users to add value to the
example, can be easily edited at once, thus allowing system as they use it.
to rapidly add ”horizontal” knowledge (across several Activity/Provenance: The system keeps record of what
instances) to the knowledge base. was contributed by whom. This includes contributions to
the ontology schema, additions of instance data or comment- • Obtain more case studies. In particular, independent
ing. This information can be used to honor active users in comparisons are needed to provide further evidence to
the context of the overall system, a specific knowledge base see whether OntoWiki lives up to its promises.
or a fragment of it (e.g. instance additions to some class).
This way it instantly gratifies users for their efforts and helps • Examine possibilities to tightly integrate reasoning ser-
to build up a community related to the edited knowledge vices (based on Description Logics) into OntoWiki.
base. • Establish better methods of interaction with existing
2.4 Semantic Search content and knowledge management systems.
OntoWiki provides a full-text search for one or multiple This paper is a more compact, updated and summarized
keywords occurring in literal property values. Since there version of [1].
can be several property values of a single individual contain- Acknowledgments: This research was supported in part
ing the search string, the results are grouped by instances. by the following grants: BMBF (SE2006 #01ISF02B), NSF
They are ordered by frequency of occurrence of the search (CAREER #IIS-0477972 and SEIII #IIS-0513778).
string. Search results may be filtered to contain only indi-
viduals which are instances of a distinct class or which are
described by the literal only in conjunction with a distinct 4. REFERENCES
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Future work will focus on the following aspects:
• Implement a privilege system and access control for
and on the basis of the RDF data model with sup-
port for rights management on higher conceptual levels
than that of statements.
5
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6
http://softwiki.de