Chapter 4 Initial Work
4.6 Reflections on the Initial Work
This chapter documents the initial investigation into adaptive hypermedia and open hypermedia by the author. Link augmentation technique, in particular, was the emphasis of this exploration.
The first system development, Link augmentation with Auld Linky, was aimed at implementing the concept of link augmentation in a selected domain. This enabled the author to obtain practical experience in implementing a simple AH system offering a straightforward approach in link augmentation. The links came from two separate linkbases which corresponded to the user profile.
The second system was designed to conduct a feasibility study in finding if the link service approach could be integrated in collaboration with a well-established AH system like the AHA! System. The preliminary study suggested that Auld Linky could initially provide supplementary links based on the current phase of the user’s
navigational path generated by the AHA! Engine. In other words, Auld Linky could only offer additional external links after the AHA! engine has already generated the main content and links of the page.
Finally, the third experiment was intended to propose a possible solution to deal with the problem with link overload. Based on the concept that a domain was made up of different dimensions of expertise and each of these expertise dimensions provided different set of links, which were stored in different linkbases, the user was delivered with different sets of links according to his or her expertise dimension and its expertise level. The use of a personalised assistant component to request supplementary links enabled the user to adjust their levels of expertise parameters in different dimensions for links presentation at any time. By allowing users to experiment with and tailor the system at runtime to choose links presentation to suit their preference, irrelevant (generic) links which were not of concern would be filtered out and only the corresponding links would be augmented and presented to the user. Thus, the user would not experience common problems such as too many links were inserted into an existing hyperdocument (‘prolific’ linking) (Carr et al., 2002), a situation when every keyword becomes a generic link (Bailey et al., 2001), and irrelevant or out of context links (El-Beltagy et al., 2002).
Table 4-2 describes a road map of the development of three AH systems. The Thai-Dutch Cookery application with AHA! served as an AH system where the user’s learning (navigation) path was generated by the AHA! engine based on an individual user’s knowledge in the user model, and the link server offered generic links for users to gain more explanation about some keywords in the cookery domain. Although there was the similarity between the Thai Cookery system and the Personalised Thai Cookery Web-based application in that they both provided the link augmentation technique, the latter facilitated users’ control over personalisation of links and its emphasis was on the idea of the implementation of different dimensions in linkbases in provision of link personalisation.
AH OH System Adaptive Presentation Adaptive Navigational Support
User’s Control Link
Augmentation
Linkbase
1st System: Thai Cookery Web site
Content fragment variants
Link hiding 2 linkbases
2nd System
Thai-Dutch Cookery application with AHA! Content fragment variants Link hiding Link removing Link disabling Link annotation 1 linkbase 3rd System:
Personalised Thai Cookery Web-based application
Content fragment variants
Link hiding 3 expertise linbases
The developments of the three AH systems provided practical experiences and generated the fundamental issues for the future direction of this work. AH provides users with adaptation of contents and links; however, the user might find it difficult to control the system’s action to make adaptation better work from them. The OH link augmentation technique offers simple adaptation by inserting additional links from a linkbase or linkbases at runtime. The adaptation process is easy to comprehend, and hence to control. However, the traditional problem with this adaptation technique is that it can introduce the link overload problem. Moreover, link presentation from multiple linkbases is not powerful because it involves hypertext authors to make coarse grained decisions about which linkbase a given link resides in. Lastly, representations of one dimension of context as one linkbase fail to support situation when one same link structure can be marked up more than once. That is, a link cannot be annotated as being a member of more than one context, for instance, being for beginners in one context and being for experts in another context. These issues pointed in the direction to this work was going forward.
4.7 Summary
This chapter has presented experiments in development of three adaptive hypermedia systems. OH techniques have been used to provide link adaptation based on the link augmentation technique. FOHM and Auld Linky were used to implement all experiments as a storage format and link provider for the client application which in turn handles the links presentation and personalisation. Each experiment provides grounding and supports the claim that the link service approach can be used as a means to make a website adaptive, particularly for a Web-based personalised navigation system.
The next chapter introduces the concept of a multi-dimensional linkbase and proposes a novel framework derived from such concept which can be used to implement an inquiry-led personalised navigation system (IPNS).