Papers in PDF format

It is important to point out that this kind of tracking may have clear positive benefits in some circumstances,
but may have a negative impact in others. For example, information about an individual's preferences and
activities might be used both to their benefit (to tailor systems to their needs) and also to their disadvantage (to
compile personal profiles). Consequently, we propose three principles to guide the application and use of
tracking techniques:
• Notification - visitors should be notified in advance of the mechanisms and policies that are in operation at
a given site so that they can decide whether to visit or not.
• Mutuality - in general, systems should be designed so as to provide some degree of symmetry or mutuality
as to awareness of presence. Thus, visitors to a site who are being monitored should be aware of the
presence of their observers. Furthermore, it might be sensible to maintain a rough balance between the
levels of information known by each party.
• Balance of power - both the observer and observed should be able to influence the level of awareness or
monitoring. In particular, it might be argued that people should not be made visible without their consent
and should not be able to become invisible without the consent of those around them.
Related Work to HyperVisVR
Related work fits into three main categories: visualizing hypertext databases, visualizing access to hypertext
database servers, and mutual awareness mechanisms for users simultaneously accessing hypertext resources.
Visualizing hypertext databases has been a hot topic at WWW and hypertext related conferences. The
approaches can be grouped into two categories. The first is those that follow a user through the WWW and
creating visual maps of browsing history, such as [Ayers et al. 1995], [Domel 1994] and [Takano et al. 1996].
Slightly different from these is HyperSpace which uses a 3D map to display browsing history, however it does
not update the visualization automatically to show the current browsing position [Wood et al. 1995]. Another
area of hypertext visualization research concerns the collection of a dataset from the hypertext database to
visualize directly. 2D visualisations include venn-diagrams [Ralha et al. 1995], graphs [Mukherjea et al. 1995]
and a distance-representing relief structure [Giradin 1996]. Virtual terrains (2.5D) have been used in the
Hyper-G Harmony browser [Andrews 1995]. Full 3D visualisations include WebViz and GopherVR. WebViz
uses a batch oriented approach to retrieve documents from a WWW server, parse them into a Hyperbolic tree
structure, and display them [Munzner et al. 1995]. GopherVR is a 3D spatial interface to the Gopher system
[McCahill et al. 1995]. Other research has focused on visualizing the access patterns on a particular server.
Lamm et al. discuss a system which displays a globe in virtual reality, and maps the level of accesses to their
WWW server from a particular geographical region onto the height of a bar extending from the appropriate
location on the virtual globe [Lamm et al. 1996]. However caches, firewalls, and service providers upset their
technique, as they mask the true origin of the browser.
Turning briefly to some of our own work in this area, the Internet Foyer is a virtual reality WWW visualization
of a set of pages, with visual representations of browsing users moving over the structure as they access the
pages and move between them. It supports mutual awareness of WWW users on the same or similar pages
concurrently. It also has a link to the real world: a real-time image of the visualization is projected onto the
wall of a real foyer, and a video wall within the visualization allows VR users to see back into the real foyer.
As such it links three spaces: the real world, VR and the WWW, and can be though of as a "mixed reality"
[Benford et al. 1996]. The Internet Foyer was the precursor of HyperVisVR, which adds fully dynamic
visualization, peer-peer networking, generic hypertext database support and plugin visualization styles.
References
[Andrews 1995] Andrews, K. (1995). Visualizing Cyberspace: Information Visualization in the Harmony
Internet Browser. First IEEE Symposium on Information Visualization, Atlanta, GA, Oct. 1995, pp. 97-104.
[Ayers et al. 1995] Ayers, E.Z., & Stasko J.T. (1995). Using Graphic History in Browsing the World Wide
Web. Fourth International WWW Conference, 1995.