Instructional Information in Adaptive Spatial Hypertext Luis Francisco-Revilla and Frank Shipman Presented By : Ananda Man Shrestha

Introduction Navigational hypertext (web) Pre-authored linking structure + Varied readers = rigid approach to information delivery Adaptive hypertext Modifies content and structure in response to user characteristics (user knowledge etc) Spatial hypertext Can represent possible relationships and implicit links. Supports direct manipulation of objects and relationships present in the document.

Introduction Goal : Create adaptive spatial hypertext document for an instructional information. Evaluate effectiveness of spatial hypertext as medium for delivery of such information. Explore the effect of adaptation in spatial hypertext.

Document Design Topic and source of information Domain : HTML/XHTML Availability of previously-authored and reputable sources of information Easy evaluation conditions (ask to author a web-page) Source : O’Reilley’s “HTML & XHTML: The Definitive Guide” Extensive coverage Clear writing, fit to readers of all levels. Available on-line

Document Design Structure of Information Usual web-sites serving instructional information provides “table of contents”, click and navigate structure. Forces user to discover underlying structure of the information throughout navigation and inference. Spatial hypertext Visually reflects structural organization of information. Visualization of relations using hierarchical arrangement, encapsulation of collections, color coding etc. Available visible information can help users take informed decision about traversing the link.

Document Design Representation as hierarchically nested lists of collection Simple Suitable for ordering sections/subsections of book.

Document Design Dynamic behaviors Open collection by pushing the list down. Simultaneous stretching in vertical or horizontal possible Using Color Codes Stretching / Pushing down the list Reminds me of gmail !!

Document Design Adaptive Behaviors System to adapt document to differentiate relevant from irrelevant information. Emphasize/De-emphasize objects by using multiple visual cues to represent varying degrees of relevance varying object size varying font size altering zoom factor changing contrast/fade of display object

Document Design Final Interface Make use of second spatial dimension.

Evaluation Experiment goal gather insights of how subjects read and interact with spatial hypertext document. Process Selected 15 subjects randomly. Subjects chosen from TAMU and neighboring areas All subjects were proficient in English Age range -> 20 to 40 years 8 subjects used adaptive spatial hypertext Task model and User knowledge model 7 subjects used non-adaptive spatial hypertext

Evaluation (contd.) Task Model : Adaptation based on what topics and subtopics are useful for authoring different types of web pages.

Evaluation (contd.) Users Knowledge Model : Adaptation in response to user knowledge (collected from questionnaire about html).

Evaluation (contd.) 20 minutes training session in the use of software applications. 90 minute time to author a web page. Process closely monitored by investigators. Questionnaires about html knowledge, demographic information, user experience and final comments/suggestions collected.

Results 2D arrangement of information was very well received by participants. 73% of participants moved the collections during their reading of the space. More participants using non-adaptive interface rearranged the layout than those using the adaptive interface (86% vs 63%) Out of 0(worst) to 6(best) scale, average evaluation Ease of understanding information arrangement = 5.6 Ease of navigation = 4.65 Ease to distinguish relevant info from irrelevant = 5.1 Visual clues to mark relevance were found to be obtrusive. Adaptation should consider user preference.

Results Users often used collections as bookmark Minimization of collections to signify completion of section Interface after task completion

Discussion Session