James Hartley
Department of Psychology, Keele University, U.K.
Key words: text design; text comprehension; writing; reading; written communication; readability; evaluation
Correspondence to:
James Hartley,
Department of Psychology,
Keele University,
Staffordshire,
ST5 5BG
UK Tel. 01782 583383.
UK Fax 01782 583387.
E-mail j.hartley@keele.ac.uk
Abstract
The aim of this paper is to indicate the nature of applied psychology and the skills that applied psychologists can bring to the area of text design. These skills are illustrated with examples from the author’s own work and that of colleagues conducted over a twenty-five year period.
People in the field of information science play a variety of roles and use a variety of skills to carry out their work effectively. Applied psychologists similarly, use a variety of roles and use a variety of skills in this respect [1]. In this paper I want to describe - using a case-history format - how I have applied my skills as a psychologist to the area of text design. My purpose in doing this is to convey the flavour of the work of applied psychologists to readers who may not be familiar with what psychologists actually do.
Text design
In terms of text design, I think there are at least six major roles and skills that applied psychologists deploy. These are:
2. to provide expert opinion, based on research and practice;
3. to develop and/or use appropriate measures to help resolve pertinent issues;
4. to establish and evaluate the evidence for different points of view;
5. to develop and test theories that will lead to new knowledge; and
6. to act as an agent for change.
research.
A different perspective
Psychologists in the field of text design often work independently, and they present the results of their deliberations for others to consider. Thus psychology makes only a partial contribution to a total team effort. However, when making their contribution, psychologists offer a particular perspective. This perspective draws particular attention to human factors. Other professionals in the team will focus, for example, on the design of the product, the methods of reproduction, and the costs of making, storing and distributing it. All of these are relevant and important, but each is only a part of the total working system. By their training applied psychologists consider problems from the point of view of the end user, and thus appear perhaps to be more conscious of the perspective of the individual in the system. This perspective, of course, is not the sole prerogative of psychologist -other professionals - human factors experts, for example, also take it - but it is one that is salient in psychology. For example, psychologists seem far more aware of the difficulties a person will have reading a leaflet in a medical package than do the producers of such leaflets [see 2, 3].
Howarth [4] pointed out that many errors in the past (in architectural planning and in the design of nuclear power station control-panels, to give but two examples) could have been avoided if psychologists had been involved at the design stage. Indeed, Howarth suggests that one of the chief functions of psychologists is to prevent other experts from 'going it alone'. In the present context of text design psychologists are thus likely to point to limitations in people's ability to read and to remember [5], to indicate how prior experience will affect how people interpret text [6], and to suggest how confusion in readers can be avoided [7].
In offering advice of this kind it is, of course, essential to be familiar with the constraints and methods of thinking and working of other members in the team. I have argued elsewhere that much of the early typographic research carried out by psychologists had little practical impact because it was not related to knowledge of this kind [8]. It was only when psychologists began to work with other practitioners in the field that their research on typography began to be of value to them. Information scientists, too, have profited from the collaboration between disciplines [e.g., see 9, 10].
Examples. Figures 1a and 1b give a good example of how a psychologist's perspective can change the appearance of text. Here the original text was produced by a teacher. I provided the suggested revision. Many other examples of this kind are provided in a series of ‘before’ and ‘after’ illustrations in my books [11, 12].
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GUIDE
"MATERIALS AND STRUCTURE" SHEET PN4 (1)
TIME: About 4 weeks NAME...................................
This GUIDE SHEET will be very important to you during your study of NUFFIELD PHYSICS PART 4, UNIT 1, and should be firmly fastened in the front of your file. This GUIDE SHEET tells you the order of doing your work.
Where you see (O) against a piece of work this means that you must see your teacher before starting that piece of work.
Where you see (M) against a piece of work this means that you must have that piece of work marked.
Where you see (T) against a piece of work this means that you must carry out that piece of work with your teacher.
Where you are told to read a section from a book etc., this means that you first of all read the section, then read it again preparing a written summary which is then placed in your file.
STAGE ITEM   ; &n bsp; MARK
1. WORK SHEET 1 (M)
2. Read Chapter 4 "The New Science of Strong Materials". A brief look
at
"Materials" - Longmans Physics Topics, would also be useful.
3. PROJECT SHEET 1 (M)
4. Discussion 1 "Choice of material" (T)
5. TEST SHEET 1
6. Read "Materials and their uses"
7. Read "Amount of substance, the mole concept, and its use in solving problems". Nuffield Advanced Chemistry Section A Chapter 1. (O)
8. TEST SHEET 2 (M)
9. WORK SHEET 2
10. Slide 1.16 (Arrange visit to Leicester University)
11. WORK SHEET 3
12. TEST SHEET 3 (M)
13. WORK SHEET 4 (M)
14. Read Pages 11-19 "Elementary Science of Metals"
15. Watch film loops "X-ray diffraction 1 & 2"
16. PROJECT SHEET 2
17. Read "The start of X-ray analysis" Nuffield Chemistry background
booklet.
18. WORK SHEET 5
19. Visit Physics Dept Leicester University. X-ray diffraction apparatus.
Write a report on the visit.
20. Slides 1.1 and 1.3.
21. Watch film loops "Diffraction of monochromatic X-rays by a powder
specimen" and "Determination of wavelength of X-rays using a diffraction grating".
22. TEST SHEET 4 (M)
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Figure 1a. A page from a school science worksheet. Note how this
suffers from poor spatial organisation and confusing text. (Figure reproduced
with permission of the author.)
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Guide Sheet PN4 (1) Name...............................................
MATERIALS AND STRUCTURE Time: about 4 weeks
This Guide Sheet will be very important to you during your study of
Nuffield Physics, Part 4, Unit 1.
Fasten it firmly in the front of your file.
This Guide Sheet tells you the order in which to do your work.
M means that you must have this piece of work marked.
R means that you must first of all read this section, and then read it again, preparing a written summary for your file.
T means that you must carry out this piece of work with your teacher.
O means that you must see your teacher before you start this piece of work.
Stage What to do   ; &n bsp; Mark obtained
1 M Work sheet 1
2 R Read Chapter 4
"The New Science of Strong Materials".
A brief look at "Materials" - Longmans Physics Topics will also be useful.
3 M Project sheet 1
4 T Discussion 1 "Choice of material".
5 M TEST SHEET 1
6 R Read "Materials and their uses".
7 O & R Read "Amount of substance, the mole concept, and its
use in solving problems.
Nuffield Advanced Chemistry Section A Chapter 1.
8 M TEST SHEET 2
9 Work sheet 2
10 T Slide 1.16 (Arrange visit to Leicester University)
11 M TEST SHEET 3
etc.
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Figure 1b. A revised version of Figure 1a.
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Expert opinion
A psychologist may be called in as an expert to advise on some topic - such as the typographic layout of a journal [e.g. see 13]. In carrying out this role of 'expert' psychologists draw upon their specialised knowledge, ideas, theories, and practical knowledge. Often, in this context, psychologists are asked to make suggestions about a proposed project and to pontificate, as it were, from on high. In this situation the psychologist usually explains that things are more complex than many people think, and points out issues that have not been properly considered. In this context these issues may be ones of human factors or typographic matters.
Example. I am reminded at this point of an editor of a new journal who asked me - as his first question - what type-size his journal should employ. I had gently to explain that a decision about type-size was not a decision that could be made on its own without first considering several other related issues - such as page-size and column widths.
Developing and using measures
Psychologists use and develop appropriate measures and techniques to help in examining and analysing problems. In terms of text design, the kinds of things I have in mind here are measures of reading difficulty and measures of reading comprehension to name but two. But questionnaires and interview schedules are also appropriate tools to use on occasions [see 14, 15]. All such measures have their own, highly complex, technology. Because of this psychologists are more aware of their limitations, and thus they are likely to use these measures with the appropriate caution that is sometimes lacking in non-experts [16].
Examples. In my work I have used a variety of measures to test the effectiveness of changes made to text. In an early paper we examined the reliability of measures such as oral reading, silent reading, scanning, searching, recalling and comprehending text [17]. We argued that different measures were appropriate for different objectives. In more recent work [12, 18], I have been at pains to point out that it is better to use a variety of methods in combination to measure the effectiveness of text than it is to rely on one measure alone. Thus, in a study of the effectiveness of different ways of presenting journal abstracts, we used readability measures, comprehension measures and reader preferences [18]. In this case all three measures provided supporting evidence for the effectiveness of the changes made.
Currently I am particularly interested in the continuing controversy over the value of 'readability formulae', particularly now that these rather dubious measures are computer-based and easily accessible to writers with word processors [19, 20]. These formulae are applied to text in order to predict its suitability for readers of different ages (e.g., 21, 22]. Despite the fact that there is wide evidence for the weaknesses of such measures in doing this [23], they are still popular. Figures 2a and 2b show two pieces of text. The shorter one of the two is generally judged to be the more difficult to understand [24] - but readability formulae suggest that the second piece is harder than the first. The comprehension measures thus suggest that the readability formulae are wrong here - and this points to the fundamental difficulty with these measures. Another problem is that different computer programs that ostensibly provide the same measure of text difficulty (e.g., a Flesch readability score) actually provide different scores for complex texts [19, 20].
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El Nino
From time to time the warm current that flows along the coast of Ecuador moves south and pushes the Peru Current away from the coast. This event is called El Nino because it takes place around Christmastime. El Nino means "the child," which is what Spanish-speaking people call the baby Jesus.
When El Nino comes, it brings bad times to Peru’s coast. Heavy rains cause flooding and landslides. Millions of fish die because the warm water has less oxygen and food. When the fish die, thousands of birds starve to death too.
In 1973, Peru’s fish catch was about 15 percent of what it had been in 1970. Part of the problem was caused by overfishing, which had begun to lower the fish supply before 1973. El Nino, however, was the main cause of the problem.
Peru’s fishing industry recovered, but it is not likely to ever reach again the high point of 1970. Overfishing, along with El Nino, nearly destroyed a valuable resource.
Figure 2(a)
El Nino
Every three to five years, the Pacific Ocean’s current changes abruptly along the western coastline of South America and causes serious economic hardship for the people of Peru. This sudden change is called El Nino, which means "the child Jesus," because it occurs right after Christmastime.
When El Nino happens two very important climate changes occur. The usually cool Pacific waters become warmer close to the coast, and there is ten times the normal amount of rainfall.
The country of Peru suffers the most from the effects of El Nino. The coastal water that is now warmer from El Nino kills millions of fish that are used to living in cooler water. Because the fish die, thousands of birds who feed on the fish die also. The extreme rainfall from El Nino causes severe flooding and landslides in the agricultural regions of Peru.
1973 was an El Nino year. The difficulties for Peru were especially serious because of another problem. The problem of overfishing had already reduced the once abundant fish supply. The El Nino made things worse by further reducing the fish supply to a very small percentage of its former level.
Peru’s fishing industry has not returned to the supply levels that existed before 1973. Since that time, El Nino has continued to affect Peru severely. As a result, Peru’s fishing and agricultural industries are still in the process of recovery.
Figure 2(b)
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Figure 2(a) and (b). An original and a revised piece of text. Note:
readers judge the longer text easier to understand, but readability formulae
indicate that it is more difficult. (Texts reproduced, with permission
from the authors and Reading Research Quarterly.)
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Establishing evidence
Psychologists are taught as students to collect and analyse data, to draw conclusions and to write reports. Psychology as a discipline emphasises the need for objectivity and controlled experimentation, and encourages its members to be conscious of the dangers of subjectivity and bias. Many applied psychologists carry out evaluation studies in order to assess the evidence for and against a particular point of view. Thus, for example, there are studies on the design of questionnaires and forms [25, 26], on the best way to show data graphically [27, 28], and on issues such as type-sizes and type-faces [29], to list just three research areas.
Some people think that the detached approach of the scientific method is frequently inappropriate for studying topics such as these [e.g. see 30, 31]. There are two main reasons for this view. Firstly, it is almost impossible to control many of the relevant interacting variables that will affect the results. Secondly, the results of one particular study are always specific to one set of conditions - and thus one cannot generalise widely from them. Attempts to overcome these difficulties require psychologists to use more flexible but less precise methods, and to carry out analyses that are more subjective [see 14, 15]. Nonetheless, I would argue that the data from these investigations are still more open and more objective than are simple value judgements. As a psychologist I argue that the biases of outside observers are likely to be less partial than the biases of those who hold vested interests.
Examples. I have carried out many experiments to examine the effectiveness of different features in instructional text. Thus, for example, I have looked at the effectiveness of summaries, headings, justified versus unjustified text, the typographic denotation of paragraphs, and the typographic design of indexes, references, and contents pages [32 - 28]. These topics, of course, have also been studied by other colleagues [see 12, 39]. On most occasions I think that issues have been clarified but, often, the results of experiments suggest additional questions that need to be explored.
In addition, a difficult issue here is how to persuade people to implement your findings. I well remember how one publisher told me that he would not follow my suggestion that he print references in a single- rather than a double-column arrangement at the end of a scientific article. References in single-columns, he firmly told me, took up more space. To test this notion I had a list of references typed in single- and in double-column versions. Much to his surprise (and mine) there was no difference in the amount of vertical space consumed. However, the publisher then replied, as firmly as before, that readers preferred a double-column.
Recently my colleague and I have suggested a considerable advantage for readers of social science journals for what are called 'structured abstracts' [40-43]. (These abstracts, which are common in medical journals, have sub-headings such as background, aims, methods, results and conclusions to make their structure clearer.) However, persuading journal editors to implement structured abstracts in social science journals has been quite difficult - but not impossible. Structured abstracts are due to appear in the British Journal of Clinical psychology, the British Journal of Educational Psychology, and the British Journal of Health Psychology from January, 1997. However, the usual response of editors is that, as such abstracts are usually twenty percent longer than ones set in the traditional format, they will - again - take up more space. In making these comments, these editors conveniently forget that much more space is often wasted in journals simply because new articles typically start on a new page, and often - as in this journal - on a new right-hand page at that!
Theories and new knowledge
Theories consist of several principles (or a collection of general interrelated principles) that are put forward as an explanation of a set of known facts and empirical findings. In collecting evidence to resolve a problem, or in giving advice, theories can suggest the underlying mechanisms or processes that might be involved. Theories can suggest where to look for causes, and how to design specific enquiries to support or reject a particular point of view.
Theories help psychologists to explain and predict on a wider scale and in circumstances that may not have been studied before. Some psychologists - such as Broadbent [44] - believed that the results from applied psychology influence theoretical psychology, rather than the reverse (see the discussion of this by Warr [45]). I myself hold the view that results from applied psychology can indeed influence theoretical psychology but that this, in turn, can influence applied psychology again.
Examples. In my own work I have viewed myself as a practitioner rather than a theorist. I believe that it is important to have data before one can start to theorise. I have expressed this view most clearly in my work on headings in text. In one paper Mark Trueman and I reported the results from nineteen experiments designed to tease out what were the important variables to consider when using headings and assessing their effectiveness [33]. We suggested that, having cleared the ground, people were now in a better position to theorise.
I suppose, though, I do hold a theory of sorts. I believe that it is the appropriate use of space rather than the typographic detailing that best depicts the underlying structure of text. Consequently I advocate the use of consistent and precisely specified rules of spacing for the production of text [12], and I do not hold with any wishy-washy statements about 'using white-space generously' to make text look attractive. In my view it is essential to be very precise about the use of space in documents.
In this respect I am particularly pleased with the evidence that I have gathered over the years about the relative importance of space rather than typographic detailing to show the structure of items such as references, contents pages, and journal abstracts [37, 38, 41]. In these studies reader preferences are clear. Readers like the structure of such text to be denoted first by its spatial arrangement, and they then like it better if the spatial arrangement is enhanced by typographic cues. But if they have to choose between a spatial arrangement without typographic enhancement and a typographical arrangement without spatial enhancement, they go for the former every time. Figures 3a, 3b and 3c show an example.
The text shown in Figure 3 is, of course, highly structured. I maintain, nonetheless, that my arguments also apply to less well-structured text. As shown earlier in Figure 1b, consistent spacing clarifies the structure of text. Clearer structures support clearer thinking.
-------------------------
Version A (the least preferred)
Loxterman, J. A., Beck, I. L. & McKeown, M. (1994).
The effects of thinking aloud during reading on students' comprehension
of more or less coherent text. Reading Research Quarterly, 29,
4, 353-367.
Version B
Loxterman, J. A., Beck, I. L. & McKeown, M. (1994).
The effects of thinking aloud during reading on students' comprehension
of more or less coherent text.
Reading Research Quarterly, 29, 4, 353-367.
Version C (the most preferred)
Loxterman, J. A., Beck, I. L. & McKeown, M. (1994).
The effects of thinking aloud during reading on students comprehension
of more or less coherent text.
Reading Research Quarterly, 29, 4, 353-367.
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Figure 3. Three different ways of presenting journal references in
increasing order of preference. Note that readers prefer most the spatial
arrangement enhanced by typographic cueing (Version C). However, if they
are not given this choice, they prefer Version B (the spatial arrangement
without typographic cueing) to Version A (the traditional arrangement with
typographic cues).
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Agents for change
Applied psychologists are involved in helping people, institutions and organisations. This means that they believe their work will change people and society for the better (whatever they perceive this to be). In this context, psychologists are concerned (i) to prevent people from making mistakes (for example by using new technology - such as word processors - inappropriately) and (ii) to enable people to communicate more effectively.
Examples. Practically everything I have ever done is imbued with these concerns. I have tried to show people that it is very easy to make mistakes but that it is not difficult to make text easier to read, and easier to use. I have done this in specialist practitioner journals, in general articles, and in textbooks. I have especially considered the implications of my work for the visually impaired [12] and for older readers [12, 46]. My prime concern, however, has been to demonstrate these ideas to psychologists in general and to my students in particular. I have tried to show people that applied psychology is rewarding.
References
[2] E. Maibach and R. L. Parrott (eds.). Designing Health Messages (Sage, Thousand Oaks, C.A, 1995).
[3] G. S. Walker, (compiler), Compendium of Patient Information Leaflets 1995-6 (Datapharm Publications, London, 1995).
[4] I. Howarth, The uses of psychology. In W. E. C. Gilham (ed.), Psychology Today ( Hodder, London, 1975).
[5] A. Baddeley, Your Memory: A User’s Guide (Penguin Books, London, 1994).
[6] D. R. Recht and L. Leslie, Effect of prior knowledge on good and poor readers’ memory of text, Journal of Educational Psychology (80) (1) (1989) 16-20.
[7] S. Kemper, J. D. Jackson, H. Cheung and C. A. Anagnopoulos, Enhancing older adults’ reading comprehension, Discourse Processes (16) (1993) 405-428.
[8] J. Hartley, Psychology and written instruction. In S. Canter and D. Canter (eds.), Psychology in Practice: Perspectives on Professional Psychology (Wiley, Chichester, 1882).
[9] E. Orna and G. Stevens, Information design, English Today 35 (9) (3) (1993) 24-30.
[10] E. Orna and G. Stevens, Managing Information for Research (Open University Press, Milton Keynes, 1995).
[11] J. Hartley, Designing Instructional Text (2nd edit.) (Kogan Page, London, 1985).
[12] J. Hartley, Designing Instructional Text (3rd edit.) (Kogan Page, London, 1994).
[13] E. C. Poulton, T. R. Warren and J. Bond, Ergonomics in journal design. Applied Ergonomics (1) (1970) 207-209.
[14] J. Hartley, Is this chapter any use? Methods for evaluating text. In J. R. Wilson and N. Corlett (eds.), Evaluation of Human Work: A Practical Ergonomics Methodology (2nd edit.) (Taylor & Francis, London, 1995).
[15] K. A. Schriver, Evaluating text quality: the continuum from text-focused to reader-focused methods, I.E.E.E. Transactions on Professional Communication (32) (1989) 238-255.
[16] P. Wright, Issues of content and presentation in document design. In M. Helander (ed.). Handbook of Human-Computer Interaction. (Elsevier, Amsterdam, 1988).
[17] J. Hartley, S. Frazer and P. Burnhill, Some observations on the reliability of measures used in reading and typographic research, Journal of Reading Behavior (7) (1975) 283-296.
[18] J. Hartley, Three ways to improve the clarity of journal abstracts, British Journal of Educational Psychology (64) (1994) 331-343.
[19] M. Sydes and J. Hartley, A thorn in the Flesch: Observations on the unreliability of computer-based readability formula, British Journal of Educational Technology (in press).
[20] R. Harris, Variation among style checkers in sentence measurement, TEXT Technology (6) (2) (1996) 80-90.
[21] G. R. Klare, The Measurement of Readability (Iowa State University Press, Ames: Iowa, 1963).
[22] C. Harrison, Readability in the Classroom (Cambridge University Press, Cambridge, 1980).
[23] A. Davison and G. Green (eds.), Linguistic Complexity and Text Comprehension: A Re-examination of Readability with Alternative Views (Erlbaum, Hillsdale, N. J., 1987).
[24] J. A. Loxterman, I. L. Beck and M. McKeown, The effects of thinking aloud during reading on students' comprehension of more or less coherent text, Reading Research Quarterly (29) (1994) 353-367.
[25] E. Kempson and N. Moore, Designing Public Documents (Policy Studies Institute, London, 1994).
[26] D. Scott., L. Gorman, A. Hartley, C. Paris, L. Pemberton, R. Power, and K. V. Linden, Characteristics of Good Administative Forms, (ITRI Technical Report No. 95-3, Information Technology Research Institute, Brighton University, 1995).
[27] M. Macdonald-Ross, Graphics in text. In L. S. Schulman (ed.), Review of Research in Education (Vol 5) (Peacock, Ithaca, Illinois, 1977).
[28] M. Siegrist, The use or misuse of three-dimensional graphs to represent lower-dimensional data, Behaviour and Information Technology (15) (1996) 96-100.
[29] A. Black, Typefaces for Desktop Publishing : A User Guide (Architecture Design and Technology Press, London, 1990).
[30] P. Burnhill and J. Hartley, Psychology and textbook design: A research critique. In J. P. Baggaley, G. H. Jamieson and H. Marchant (eds.), Aspects of Educational Technology, (Vol VIII) (Pitman, London, 1975).
[31] M. Macdonald-Ross, How numbers are shown: a review of research on the presentation of quantitative data in text, Audio-Visual Communication Review (25) (1977) 359-409.
[32] J. Hartley and M. Trueman, The effects of summaries on the recall of information from prose: five experimental studies, Human Learning (1) (1982) 63-82.
[33] J. Hartley and M. Trueman, A research strategy for text designers: the role of headings. Instructional Science (14) (1985) 99-155.
[34] J. Hartley and R. Mills, Unjustified experiments in typographical research and instructional design, British Journal of Educational Technology (4) (1973) 120-131.
[35] J. Hartley, P. Burnhill and L. Davies, The effects of line-length and paragraph denotation on the retrieval of information from prose text, Visible Language, (12) (1978) 183-194.
[36] J. Hartley, P. Burnhill and L. Davies, Typographic decision making: the layout of indexes, Applied Ergonomics (8) (1977) 35-39.
[37] J. Hartley, M. Trueman and P. Burnhill, The role of spatial and typographic cues in the layout of journal references, Applied Ergonomics (10) (1979) 163-169.
[38] J. Hartley, Designing journal contents pages: the role of spatial and typographic cues, Journal of Research Communication Studies, (2) (1980) 83-96.
[39] E. R. Misanchuk, Preparing Instructional Text: Document Design Using Desktop Publishing (Educational Technology Publications, Englewood Cliffs, N. J., 1992).
[40] J. Hartley and M. Sydes, Structured Abstracts in the Social Sciences: Presentation, Readability and Recall (British Library R & D Report No. 6211, British Library, Boston Spa).
[41] J. Hartley and M. Sydes, Which layout do you prefer? An analysis of readers’ preferences for different typographic layouts of structured abstracts, Journal of Information Science, (22) (1) (1996) 27-37.
[42] J. Hartley and M. Sydes, Obtaining information accurately and quickly: Are structured abstracts more efficient? Journal of Information Science (22) (5) (1996) 349-356.
[43] J. Hartley and M. Sydes, Are structured abstracts easier to read than traditional ones? Journal of Research in Reading ( in press).
[44] D. E. Broadbent, Relation between theory and application in applied psychology. In P. B. Warr (ed.), Psychology at Work (Penguin Books, Harmondsworth, 1971).
[45] P. B. Warr, (ed.), Psychology at work (4th ed.) ( Penguin Books, London, 1996).
[46] J. Hartley, Designing instructional text for older readers: a review, British Journal of Educational Technology (25) (1994) 172-188.