Edinburgh Napier University

  This thesis investigates the usability of an 800 page textbook compared with a hypertext
version containing the same information. Hypertext is an interesting new medium in that it is
seen as possessing advantages as both delivery technology that influence cost and access to
information and design technology influencing student achievement. Unfortunately the
proclamations of its advocates have usually exceeded empirical findings. Also, rapid advances
in both hardware and software are necessitating the frequent re-evaluation of contemporary
hypertext.
In addition to an up-to-date evaluation of the relative performance of book and hypertext
supporting set tasks, the research reported in this thesis also sought to specifically analyse the
potential role individual differences could play within media evaluation. To do this the
cognitive styles and spatial ability of 57 postgraduate student volunteers, from two computer
related diplomas, were measured. Half the subjects were then randomly assigned to a Book
group and half to a Hypertext group. Each group was then allocated the same amount of time
to complete two separate tasks: 1) short answer questions analysing the basic information
retrieval potential of each medium, and one week later 2) four open-ended short essay
questions. Surprisingly, subjects assigned to the Book group performed significantly better
than those assigned to the Hypertext group for Task 1. The mean academic performance of
subjects (the mean mark obtained over the 8 modules of their diploma) predicted most
variance in Task 1 performance for both groups. However, with Task 2, the cognitively more
demanding exercise, none of the measured individual differences could significantly predict
the scores of subjects. Another surprising finding, given that all subjects were studying
computing, was that the amount of prior computing experience was found to approach
significance for those subjects assigned to Hypertext for Task 1. Given the ease with which
this particular individual difference could be manipulated it was decided to run a second
experiment employing -subjects with more experience of the Hypertext system used. The
results from this second cohort showed no significant differences in score for either task
between Book or Hypertext. However, as the more qualitative data from a questionnaire
showed, there are a large number of different factors and issues that contribute to the ultimate
acceptability of one medium compared with the other.
The thesis concludes by recommending a number of possible avenues for future research
looking at the role hypertext has to play in the construction of hyperlibraries and Virtual
Learning Environments.