21.3 Hypertext and Learning

For over 40 years, technological "solutions" have been offered to the teaching profession in order to improve their effectiveness, ranging from programmed text and teaching machines through to the modern fascination with computers. Areas such as computer-based learning (CBL) or computeraided instruction (CAI) aim to provide some of the functions of the teacher (see 2.3.2, 12.1, 19.2.2). The technologist's dream, of course, was the provision of a workstation for every learner so that they may proceed at their own pace, and to some extent the dream remains today. However, between the earliest teaching machines and the latest hypermedia environments, there has been a radical shift in prevailing pedagogy, from the repetitive reinforcement schedules of the behaviorists through the cognitivist movement and latterly the constructivists. Each movement has sought to make the technology its own and can make a case for the use of hypertext in its own terms (see 2.2.1, 5.5, Chapter 7).

It is not our intention to expound these arguments here. Suffice it to say that few theorists of any philosophical persuasion within the learning discipline have been able to specify a distinctive learning environment within the technology that uniquely supports their position. Indeed, critics of the old behaviorist teaching machines characterized the technology as betraying a crude, mechanistic model of learning where teaching reduces simply to optimizing the presentation of materiala criticism not lessened in any way by improvements in technology per se.

Within education, hypertext has been seen by some as a valuable new constructivist tool (see 7.1) for supporting teachers and students (Cunningham, Duffy & Knuth, 1993), whereas others have seen it as simply a fancy new "jug" (Whalley, 1993). There is merit in both positions, but for us the crucial point is that the argument is currently showing no sign of resolution, since neither side's claims have been subjected to sufficient empirical testing.

The perceived advantages of hypertext as an educational medium are usually ascribed to its nonlinear property. This is often contrasted with the assumed linearity of traditional text, for example: "In contrast [to hypertext] most standard text documents are constructed to be read linearly, from beginning page to ending page" (van den Berg & Watt, l991,p. 118).

We have discussed the myth of linear text at length elsewhere (McKnight, Dillon & Richardson, 1991). Suffice it to say that most texts are not constructed to be read from beginning to end. This becomes blatantly obvious after the briefest of observations of people using "standard" text documentse.g., journal articles, course textbooks, encyclopedias, and newspapers. How are you reading the book you are holding? Did you reach this page after reading all the preceding pages, or did you browse the contents and flick through and glance at some chapters before deciding which to read now? Even within this chapter, you may have glanced at the references first (have we referred to your work?), skipped sections (maybe you are not interested in the historical roots of hypertext), and so forth. Apart from the novel, very few texts are constructed to be read linearly in their entirety. As we have pointed out elsewhere, even the novel may be used in many nonlinear ways in, say, a literature class in tertiary education (Dillon & McKnight, 1990).

Hypertext has certainly become a popular term to be bandied about in education, not surprisingly since it is relatively new, technically impressive, and, until the novelty wears off, often fun to use. A brief search of the literature from 1989 to 1993, using the search terms hypertext OR hypermedia AND learning will yield over 100 references. The issues covered and the disciplines and journals represented are many: using multimedia with Navajo children to alleviate problems of cultural learning style, in Reading and Writing Quarterly; monitoring hypertext users, in Interacting with Computers; hypertext in cognate-language learning, in the Journal of Computer Assisted Learning; opportunities for hypertext in interactive learning, in the Journal of the American Society for Information Science.2

Unfortunately for present purposes, very few of these report on the systematic evaluation of hypertext in an educational setting. By systematic evaluation, we mean the empirical testing of real users interacting with the artifact in an ecologically valid task. The vast majority either say how wonderful hypertext is or might be, or describe some hypertext-based courseware in detail without evaluating its effectiveness. Some even equate Apple's HyperCard with hypertext, assuming that if it is built in the former, it must be an example of the latter (e.g., Horton, Boone & Lovitt, 1990). Although these authors do perform an evaluation, their results provide evidence for computer-aided instruction rather than hypertext.

One of the earliest attempts to evaluate hypertext's potential in a learning environment was that reported by Beeman et al. (1987). Their paper reports on attempts to use the Intermedia hypertext system in two of Brown University's existing coursesan English literature course and a plant cell biology course. The evaluation of the effect of introducing hypertext was far from easy. Each of the courses was closely observed by a team of social scientists, once prior to the introductior~~of the hypertext and once when the hypertext materials were in use. Instructors and students were interviewed several times throughout the evaluation; a group of students was asked to keep diaries of their activities during the time the courses were taught; and the use of a specially set up computer laboratory by both students and instructors was monitored.

At first sight the effects of introducing hypertext seem to have been positive. Beeman et al. report a small positive correlation (r = 0.29 at 0.05 level of confidence) between high Intermedia use and high grades. However, they also report an unexpected finding that suggests that improvements may not have been attributable to the introduction of hypertext per se, but rather to factors related to its introduction. Because the Intermedia workstations were not ready in time, the professor in charge of the English course was forced to teach the course without using the system but having already prepared the Intermedia material. The result of this was that he changed the way he taught the course and subsequently felt that students grasped 'pluralistic" reasoning styles better than in previous years. Furthermore, the students were more satisfied with the course than in previous years. This suggests that the need to rethink the course design may have been the major contributor to the improvement in grades. A professor who has taught the same course for years may not be as "inspiring" as he used to be, but interest may well be rekindled and communicated to the students by having to redesign the course for a new medium.

A further difficulty in making any strong statements about the apparent improvements in grades is also raised by Beeman. By themselves, the studies offer no evidence that the style of thinking fostered in these two courses transfers to other courses. As Beeman points out, students are generally good at adapting to teachers because they are interested in doing well. Hence, their results may indicate a coursespecific adaptation rather than a genuine change in thinking style. However, it would be extremely difficult to test such an hypothesis, since it would involve the comparative evaluation of students across many courses.

The Beeman studies are an excellent illustration of the difficulties involved in assessing the effect of introducing not only hypertext but any new teaching technique or technology into an educational context. The Hawthorne effect, so-called because of the industrial context in which it was first systematically observed, is just as likely to appear in an educational setting. Furthermore, Beeman's most interesting conclusion was that the significant learning effects observed through the use of Intermedia were more pronounced for the people involved in producing the materials rather than for students using the system, apparently substantiating the adage that "the best way to learn something is to teach it!"

Despite the topic of learning having formed a major section of psychology for many years, we still know very little about the cognitive processes of learning. As psychologists we recognize this as a parlous state of affairs, since many people recognize the ability to learn as a key attribute of human behavior. From the outset, psychology has sought to define, explain, and predict learning, from associative principles to laws of effect, from principles of reinforcement to cognitive skill acquisition, from mental model acquisition to constructivism. However, as Norman (1980) states boldly, "it has all come to nought." Learning, once the backbone of psychology, is now rarely found as a major component of psychology degrees but resides in specialized subdisciplines such as education. While this might be interpreted as a position of strength engendered by the subject's inherent importance, such a position is hard to justify in the absence of similar developments for other major psychological issues such as thinking, memory, perception, social interaction, and so forth. In effect, 100 years of studying learning has provided little by way of systematic knowledge for ensuring desirable learning outcomes. Hence, evaluating the interactive technology to support this process is by no means straightforward.

Hammond (1989) claims that we seem to be good at providing some appropriate environments for learning:

. . . in teaching a child to talk, the parent merely needs to give appropriate stimulation at appropriate times; details of intermediate states of knowledge and the processes of acquisition can safely be left to the child and to the research psychologist (p. 172).

This comment is telling in that it suggests that "merely" providing the appropriate stimulation at the right time might have the desired results (a rather Skinnerian perspective for such a cognitivist to take, though with obvious Chomskian resonance!), with the learners themselves doing the rest. If this really is the best we can do, then psychology's role is less to worry about the nature of learning than to concentrate on the provision of suitable environments . . . and hypertext may be one such environment.

Harnmond and Allinson (1989) suggest that hypertext can provide the basis for an exploratory learning system, but that by itself it is insufficient, needing to be supplemented by more directed guidance and access mechanisms. In order to investigate this suggestion, they conducted an experiment in which all subjects used the same material held in a hypertext form, but with differing guidance and access facilities available. The baseline group had a basic hypertext with no additional facilities, while other groups had either a map or index or guided tours available, and a final group had all three facilities (map, index, tours) available. Half of the sub

jects were given a series of questions to answer while accessing the material (a directed task), while the other half were instructed to make use of the material to prepare for a subsequent multiple-choice test (an exploratory task).

Perhaps surprisingly, Hammond and Allinson report no reliable differences between task conditions for the three groups, which had a single additional facility, although in all three groups the facilities were used to a substantial extent. However, in the group having all three facilities available, there was a significant task-by-facility interaction. Those subjects performing the exploratory task made little use of the index but significant use of the tours, while those performing the directed task made little use of the tours and far more use of the index. Thus, Hammond and Allinson argue that after only 20 minutes, subjects were able to employ the facilities in a task-directed manner.

The additional facilities also allowed more accurate overviews of the available material and resulted in a higher rate of exposure to new rather than repeated information. However, there were no significant differences in task performance between groups. Hammond and Allinson attribute this lack of difference to the fact that neither of the tasks required any strategic organization of the material, and they therefore caution against extrapolating such results to situations other than simple rote learning of relatively unstructured material. Indeed, even the subjective judgments of the subjectsthat the system was easy to use, getting lost was not a major problem, and the system was rated as "better than a book" should be viewed in the light of the fact that the hypertext used was very small (consisting of only 39 information screens), and subjects only used the system for a maximum of 20 minutes. Although it discusses "learning support environments" and is clearly aimed at an educational context, Hammond and Allinson's work provides a contrast to the Beeman study in that its strength is its controlled, experimental nature, whereas the strength of Beeman's work is its applied, "real world" nature. Both types of study have a role to play in the attempt to discover the effects of hypertext in education.

Stanton and Stammers (1990) suggest that the reasons why a nonlinear environment might be superior are that it (a) allows for different levels of prior knowledge, (b) encourages exploration, (c) enables subjects to see a subtask as part of the whole task, and (d) allows subjects to adapt material to their own learning style. In their experiments (1989, 1990), one set of subjects was given the freedom to access a set of training modules in any order, while another set of subjects was presented with the modules in a fixed order. They reported that performance was significantly improved when subjects trained in the nonlinear condition. Although such comparisons may provide valid experimental designs, extrapolating the results to realistic learning situations is difficult, particularly in higher education where students are rarely forced to access material in a rigid, predetermined order. Hence, the results may reflect the advantage not so much of nonlinear environments but rather of giving the learner some degree of control over the learning environmenta return to the more straightforward notion of providing accessible material and letting the learners "get on with it" themselves.

It could be argued that a hypertext environment does provide for greater learner control and therefore possesses advantages over traditional paper-based learning materials. However, this suggests two equally plausible interpretations: greater control over the user's access to the hypertext's contents by way of the links provided by the author/designer, or greater control by users because they are free to follow the pathways of their choicean option that is allegedly more difficult with printed text. The second option seems more optimistic and attractive, but experience does not give much encouragement. Given the option of following their own path through a hypertext courseware or taking a path suggested by the tutor, how many are likely to follow their own inclinations? Furthermore, how many tutors would put as much energy into generating paths through the hypertext which support a stance antithetical to their own? Students using hypertext courseware will tend to follow the paths provided by the course tutor or hypertext author. If either of these possibilities is true, then a hypertext courseware may prove more constraining than the books it replaces, which can be opened at any page.

In principle, the whole of a book or journal volume is available to the reader simply by turning page after page, whereas in hypertext, the learner is at the mercy of the author, reliant on his having provided suitable links (see 12.2.3.5.4). Even if learners are given the facility to add their own links, they must have seen the nodes at both ends of the link in order to make the judgment that a link is desirable. This makes the process of adding links seem a little more "hit-and-miss" than it is usually described.

Although the notion of control is an important one in education, it is far from clear that hypertext provides the learner with more control than traditional media. While Duchastel (1988) states that computers promote interaction through a manipulative style of learning where the student reacts to the information presented, the fact that the learner is using a mouse to select items and move through the information space does not make the process any more "active" than consulting an index, turning the pages of a book, underlining passages, and writing notes in the margin. In the main part, interactivity in education comes, as it has done for over 2,000 years, from verbal discourse.

If current hypertext systems appear to provide greater opportunities for learner control and best support exploratory styles of learning, this may in part explain the excessive zeal among their proponents for the importance of these aspects of learning. Romiszowski (1990) provides a welcome degree of caution:

There is, however, some doubt as to whether all these process-oriented aspects of hypertext systems are necessarily "a good thing" in all manner of learning situations. The research on learner control of the learning process is, to say the least, mixed. There is much evidence to suggest that learners, when free to select their own strategies, do not always select wisely" (p. 322).

This echoes earlier suggestions that the majority of students are not able to set learning objectives for themselves and study autonomously (Bunderson, 1974; O'Shea & Self, 1983). Many undergraduate programs start with study skill courses.

A heavy emphasis on exploratory learning for younger students may soon, if not already, be seen as yet another progressive enthusiasm that flowered in the 1960s. Today it is more likely to be seen as just one useful tool in the teacher's armoryperhaps a stimulus and motivator to be used at regular intervals between sessions of more structured classwork.

At the other end of the student age spectrum, access to a wide-ranging and richly interconnected hypermedia database may be of real interest to, say, the fledgling humanities Ph.D. candidate who is trying to identify common factors that have influenced a diverse range of human activities. The term J?edgling is used intentionally, since who else will incorporate primary documents that are accessed so very rarely (unless thesis requirements are changed to dictate that all referenced material is incorporated into the hypertext "canon"!) Undergraduates will probably still feel so overwhelmed by the extent of their workload that following associative flights of fancy, rather than sticking to the prescribed texts of the reading list, will seem at best a luxury if not sheer folly. As Whalley (1990) points out: "The hypertext reader might flit between the trees with greater ease and yet still not perceive the shape of the wood any better than before."

The scientific principle of parsimony, of adopting the most simple explanation, is worth applying to learning and the new media. "Pluralistic reasoning" to some is "confused tbinking" to others, and given the far-from-certain results of much cognitive psychological work on mental representations and knowledge construction, as well as the ongoing revisionism in the educational field, we might best consider hypertext as an information-accessing medium and the learner as a seeker of information before positing elaborate notions of thinking style that prove difficult to validate empirically.

Adopting such a perspective allows us to shift our concern from theorizing about the mental activity of learning to designing an information environment that can support task performance. We will return to this point later, but before outlining an approach that could help improve the design of hypertexts, we will review some of the studies that have actually attempted, with varying degrees of success, to evaluate hypertext systems in an educational context.

In a study by Gordon and Lewis (1992), 80 subjects read a tutorial about a t state-of-the-art hi-fi videocassette recorder in either a linear format or one of two hypertext formats (unconstrained network or constrained structure). They were then asked to summarize the tutorial, answer a series of questions, and solve two problems using the hi-fi VCR to perform particular tasks. For the factual questions, subjects using the linear form of the information scored significantly higher than either of the hypertext groups, which did not differ from each other. For the problem-solving tasks, subjects using the constrained hypertext performed equivalently to the linear subject, with the free network subjects perforrning significantly worse. The authors conclude that: "If it is critical that students learn the details of material in a document, the instructor cannot rely on the student to hypertext [sic] through the information and acquire it; linear formats should probably be retained" (p. 307). It is a pity that these authors did not include a condition in which subjects used the traditional paper manual.

A study by Higgins and Boone (1990) compared the effectiveness of a hypertext study guide used either in combination with or instead of lectures. Forty ninth-grade students (mean age 14.6 years) enrolled in a course in Washington State history took part. Of the 40, there were 10 with learning disabilities, 15 remedial students, and 15 regular students. They were randomly allocated to the three conditions of (1) lecture alone, (2) lecture plus study guide, and (3) study guide alone. Their results led them to conclude that "The hypertext computer study guide is as effective an instructional medium for students with learning disabilities, remedial students, and regular education students as a wellprepared lecture, as measured by recall and retention of information both factual and inferential" (p. 539). They drew identical conclusions for the combination of study guide and lecture and suggested that the study guide could provide some students with the practice necessary to increase quiz performance. Strangely, the authors appear not to have considered subjective preference. If there was not much to choose between them in terms of outcome, then the more attractive system has a major advantage in terms of student motivation, especially with less able students.

Despite our criticism above of van den Berg and Watt's (1991) view of text linearity, the study reported in their paper is worthy of consideration. In a design similar to that of Higgins and Boone (1990), they compared the effectiveness of a hypertext document containing material on introductory statistics and hypothesis testing. In a "competitive" condition, a random sample of 28 students used the hypertext during a 6week period when they did not attend lectures, while the remaining 81 students continued to attend lectures. In a "supplementary" condition, 30 randomly selected students were given the hypertext to use at their discretion, while the remaining 72 were not allowed access to it. In the "replacement" condition, the hypertext served as the sole source of instruction, and there were no accompanying lectures. These conditions were run over three consecutive semesters; subjects were senior-level communications sciences majors.

Interestingly, although there were no significant differences in the objective performances of the groups, the subjective acceptance of hypertext was highest in the supplementary condition and lowest in the competitive condition. The authors suggest that subjects in the competitive condition may have been influenced by the contrast between being left to their own devices compared with the guidance they perceived the control group receiving. They conclude that the most suitable use for hypertext might be as a replacement for in-person instruction where teaching is not available.

Jonassen, one of the most prolific of authors in the field of hypertext and learning, recently reported on a series of three studies attempting to evaluate hypertext (Jonassen, 1993). In terms of structural knowledge acquisition, Jonassen was forced to conclude that his results called into question "the ability of learners to engage in meaningful learning rather than information retrieval from hypertext, especially in the context of a learning environment" (p. 165). Far from being the "natural" learning environment that somehow reflects semantic memory, Jonassen suggests that "A fair evaluation of learning from hypertext can only come from hypertext-literate learners who have developed a useful set of strategies for navigating and integrating information from hypertext" (p. 165).

Marchionini and Shneiderman (1988) have suggested that hypertext is more suited to browsing than directed retrieval tasks. Following from this suggestion, Jones (1989) hypothesized that more incidental learning would occur in a browsing task than in a task requiring the use of an index. The argument advanced by Jones was that the links in a hypertext node represent an embedded menu and that the context provided by the node should encourage the connection of the ideas at either end of the link. In other words, the learner's semantic net is more likely to be elaborated or more learning is likely to occur.

Two groups of subjects were used in Jones's experiment. Both groups used the same hypertext database, but one group was shown how to browse through the information using the links and were explicitly instructed not to use the index, while the other group were instructed in the use of the index and were not informed about the active nature of the highlighted words on screen (which were described to them as "clues to other index entries"). Subjects were given 5 questions to answer from the database, but afterwards were given 10 questions to measure incidental learning.

Although Jones's argument has intuitive appeal, her experiment failed to support her hypothesis. No significant differences were observed in terms of performance on the incidental learning questions. It is possible that the nature of the questions given to the subjects to answer from the database did not encourage incidental learning. This is certainly suggested by the low overall success level of subjects on the incidental learning testthe highest mean number correct for any group was 1.56. Even in the five target questions, taking all groups together, no question was answered correctly by more than half of the subjects. This suggests that the task was not patticularly sensitive to the effect of the experimental manipulations, and hence we can do little more thari agree with Jones that "much more research is needed."