iMapping is a visual technique for structuring information objects. It is based on research in the fields of visual mapping techniques, Information Visualisation and cognitive psychology. iMapping uses a Zooming User Interface to facilitate navigation and to help users maintain an overview in the knowledge space. An iMap is comparable to a large whiteboard where wiki-pages can be positioned like post-its but also nested into each other. Augmenting Wikis by providing spatial browsing and zooming facilities makes it easier to structure content in an intuitive way. Especially semantic wikis, which typically contain more fine-grained content, and stress the structure between information items, can benefit from a graphical approach like iMapping, that allows to display multiple such items and multiple wiki-pages in one view. This paper describes the iMapping approach in general, and briefly how it will be applied as a rich client front-end to the SemWiki engine.
Wikis have proven to be useful devices to easily store and manage structured
information, and are also increasingly being used for Personal Knowledge
Management. Semantic technologies however have not found widespread use so far. Using
wikis to also author formal (semantic) knowledge structures seems a promising
approach. However for these semantic technologies to be widely used, it is crucial
that they are very easy to author and that they do not constrict the user in his
work. Also hypertext research has shown, that users often get “lost in
hyperspace” when browsing complex hypermedia without additional navigational help
[
When semantically formalised knowledge structures are being used, content typically becomes more fine grained and the content structure, i.e. the relations between objects gain importance. This stresses the need for user interfaces that facilitate navigating and authoring such structures without loosing orientation. Nowadays’ ontology editors appear to be too complicated for every-day lightweight use. Outside the wiki and semantics world however, exist quite a number ot visual mapping techniques (like Mind-Maps, Concept Maps and others), that provide easy ways to rather intuitively structure fine grained bits of information.
iMapping is a new visual mapping approach based on Zooming User Interfaces, that tries to combine the strengths of several established mapping techniques and go beyond them. It is meant to support easy informal note taking as well as semi- and fully formalized knowledge engineering in the same powerful yet easy-to-use environment.
An iMap is like a large pin board, where wiki pages can be spatially arranged thus enabling users to gain visual overview over several wiki pages at once. Besides classical browsing, an iMapping-enabled wiki can be navigated by zooming through. We believe that the iMapping approach may well facilitate the use of wikis-especially when they go semantic. 2
Since external knowledge repositories like wikis usually represent human
knowledge and are maintained by humans, it appears sensible to make the UI as
cognitively adequate as possible, to enhance the link between mental and external
models. Unlike text, diagrammatic knowledge representations carry a structural
analogy to the content they represent. In other words: A diagram’s structure
looks similar to the structure it is about. A map of Europe looks somehow
like Europe from above. A flow-chart depicts the structure of a process. A text
doesn’t—It takes a longer way in the user’s mind until it can be related to the
user’s mental model [
Microcontent Some Wikis, like e.g. SnipSnap 1, already allow including other wiki pages in a page so, instead of having to follow a link, the user can see the target page inline. This is a first step into the direction of microcontent (”content that conveys one primary idea or concept [and] is accessible through a single definitive URL” 2), which is useful to avoid redundancies, because most pieces of information are relevant in different contexts. In the same way, pages can be nested into other pages in an iMap. This leads to a different conceptualisation of what a wiki page is: many pages will just be little snippets of text, while other pages will mainly contain such snippets or other resources, thus functioning as aggregators.
Semantic Desktops and Wikis One of the first Semantic Desktop systems,
that lets the user freely specify semantic relations between typed information
items on a topic maps basis, is DeepaMehta [
DeepaMehta keeps it in a background repository on the server independent from
whether they are still part of an actual topic map. This separation between the
structural model and visual model makes sense, also for iMapping, because it
allows multiple (visual) instances of an item to be used in different contexts or
locationsmuch like hard links in a Unix file system. Some Semantic Wikis like
SemWiki [
Visual Mapping Techniques Visual mapping techniques are methods to
graphically represent knowledge structures. Most of them have been developed
as paper-based techniques for brainstorming, learning facilitation, outlining or to
elicit knowledge structures. Some of them have proven to be very useful in
Personal Knowledge Management, especially for tasks like gathering and structuring
ideas and acquiring an overview on a certain domain. For an overview on visual
mapping techniques, their cognitive psychological background and an evaluation
of some existing techniques and tools, see [
Mind-Maps for example, provide an easy-to-understand tree-like structure useful for outlining a topic or sorting items. But it is suitable to depict the relational structure between items.
Concept Maps on the other hand have a graph-based structure that emphasizes these relations. But they are not as easy to handle, because explicitly specifying all these relations is too laborious e.g. for a fast gathering of keywords.
“Spatial Hypertext” is yet another approach. The basic idea is to view a
self-contained hypertext (like a wiki is) from an overview perspective, drilling
down to single pages (which tend towards microcontent). However the Spatial
Hypertext paradigm expressly abandons the concept of explicitly stating
relations between objects and uses spatial positioning as the basic structure. To
fuzzily relate two objects, they are simply placed near to each other, but maybe
not quite as near as to a third object. This allows for so-called “constructive
ambiguity” [
Zooming User Interfaces An early research prototype using a zooming
approach was Pad and its successsor Pad++, both developed in Maryland 4. It
has been used in various applications and also as a web browser capable of
showing the viewed web pages and their link-structure from a birds view. In a study
3 For more information on Semantic Desktop systems in general, see http://
semanticdesktop.org
4 see http://www.cs.umd.edu/hcil/pad++/
where participants had to p erform browsing tasks in order to answer some
questions, sub jects using Pad++ were 23% faster than those using Netscap e [
A
Semantic
Desktop system whos
UI is deeply based on zo oming is
MentalSky 6 . It uses machine-learning metho ds to semantically classify existing resources into clusters that can b e browsed by zo oming through and restructured with drag-and-drop interaction.
MentalSky is currently in a prototyp e state of development. It strongly differs from an iMapping based semantic wiki in the resp ect, that it is constraint to managing external resources (like files, pictures, web-links, etc.) but is not made for authoring content neither in plain text nor in a formal way.
iMapping iMappping Related Work iMapping Design Principles )#-&+-7(."#$%&$'&8()01 $)&+/*G6-)$,(+*&$%4-2$)8(5+'$,G+*+&+-&+9$ page=MentalSky iMapping tries to combine the advantages of all the above approaches: – basic wiki functionality (collaborative editing, easy linking, backlinks etc.) – visual knowledge representations with structural analogy to content – easy hierarchical overall topology – facility for graph-based relation mapping – support for formal semantic statements – allowing constructive ambiguity – provide overview by integrating context and detail through zooming Basic Hierarchy The basis of the iMapping paradigm is a large two-dimensional surface, where items can be freely placed. In a wiki context, these items mainly correspond to wiki pages. Because these items can contain other items, it is encouraged to use microcontent rather than long unstructured texts. Whereas in Mind-Maps or other tree-like diagrams the lower hierarchies branch towards the outside from a central point, in an iMap hierarchy goes down into deeply nested nodes that can be zoomed into (see Figure 1). Like explained above, there can be multiple visual instances of one and the same information object, because it may be relevant in different contexts.
Other Content Instead of a wiki (text-) page, a node could also contain things like a picture or other structured objects. It can basically be seen as an inline link to any resource for which a display method is known. Even inter-wiki or other remote content could be included inline like that.
Levels of Detail Because some information objects (like most text-pages) are rather hard to recognise when they are scaled down to thumbnail size, the nodes should have at least two possible states: open and closed, which could also be seen as expanded / collapsed or being outside / inside the node. Switching between these states is done either manually per click or can take place automatically, depending on how large the object is displayed. This method is also sometimes referred to as “semantic zooming”. A wiki page could be represented by its name in collapsed state and with its content in expanded mode. A more structured article could show his title only from a distance, when zoomed larger also some additional information like authors and date and when zoomed to reasonable size, fade over to the full content. Structuring content in the ABCDE format7, facilitates such semantic zooming.
the one hand, giving an to the structure and relations b etween information items is one of the main b enefits of the iMapping approach. On the other hand, just drawing arrows for every link or even every semantic relation and backlinks to any other item would result in a complete mess sometimes referred to as the “spaghetti syndrome”.
The idea in iMapping is, to not show any relations by default, and only make them visible on demand (see Figure 2). This could b e a subtle interaction like mouse-over or something more explicitdep ending on user settings or a mo de.
Not only naming or even typing links but graphically drawing them b etween ob jects in a concept map (no de-and-link) style would go even further b eyond common wiki functionality. However it is a common and well-evaluated technique that is useful for depicting and authoring relations b etween information items. Such links have of course to stay p ermanently visible. In the same way, it is p ossible to semantically interrelate items by simply drawing links b etween them, which can than b e typ ed. If this is done using auto-completion, reuse of existing relation typ es is fostered.
iMapping iMappping Related Work iMapping Design Principles
!"#$%&'()*+$,,"%.%/01"23"*45'12'%3*'%*!,$&'$1*+6,"7&"8& !"#$%&'()*+#$,&-.&/)0(#12&/33"1,&4"115#+&/#233",&6#371)&68)1(,&9#:(;&<%%#*1==) )#-&+-7(."#$%&$'&8()01 $)&+/*G6-)$,(+*&$%4-2$)8(5+'$,G+*+&+-&+9$ Whether the iMapping approach will be successful, user studies and time will have to tell. It is a concept so far. A first prototype environment is under development and might be available by mid 2006. While our implementation is based on a java client to take advantage of the Piccolo framework (s. above), a flash- or SVG+AJAX-based version would allow browser-based usage, which would come closer to common wiki use.
Also, since the iMapping approach was initially designed for personal use, there might be unforeseen difficulties when used in a collaborative setting, like most wikis are. For example, there could be dissent on how items should be spatially arranged. But hopefully, like it is common in wiki culture, over time layouts will converge to a structure that finds consensus. Another approach would be to use personal profiles to let users make their personalised spatial arrangements of the content. The better the content and its structure represented using defined semantics, the easier it is to separate it from its visual appearance and to syndicate it to other applications. 5
Wikis have started as very simple content management systems and many engines have grown immensely feature-rich by now. The step to semantic wikis is very promising and could give the realisation of the Semantic Web a significant boost. But it surely doesnt make these wikis easier to use. Focussing on user interaction and cognitive ergonomics will be an important point, if semantic wikis are to become widely used whether collaboratively or for personal knowledge management. In the Open Source Social-Semantic-Desktop Project Nepomuk8, a first iMapping Wiki is being developed, and anticipated to become available during 2007. It will then become part of a more comprehensive knowledge workbench integrating Semantic Desktop functionalities like application integration, and semantic search with a distributed p2p-based collaboration environment.
Research reported in this paper has been partially financed by the EU in the Social Semantic Desktop project NEPOMUK (IST-FP6-027705). I would also like to thank Benjamin Heitman for fruitful discussions and last-minute technical assistance.