

                                     CHAPTER II

                              REVIEW OF THE LITERATURE


                                Introductory Comments

                   Since the late 1980s, hypertext investigators have
             proclaimed this technology as a major advance in electronic
             information retrieval and publication systems.  Yet as of
             mid-1991, the Compact Disk-Read-Only-Memory (CD-ROM)
             version of The Oxford English Dictionary on Compact Disk
             (1987) <refs -oxford> is the most significant of the few
             commercially distributed hypertext "publications" or
             products.

                   Hypertext literature and research has reflected a
             primary orientation toward the technology of
             implementation. There has been much attention to the
             subject of optimal user-interface design and to advances in
             hypertext display technology. There has been little
             attention in this country to the information organizational
             and information access concepts used in hypertext system
             building.

                   The first section of this chapter examines the
             literature concerning the broader background of established
             library and information retrieval techniques. This section
             will not consider the specifics of information retrieval
             system design and operations. It instead examines the
             general background and development of information retrieval
             system concepts and design. The literature included here
             will be more concerned with "exactly what are we trying to
             do?" questions, rather than with the specifics of
             information system implementation. The review will present
             an overview of major contributors and principles of
             organizing or structuring access to information.

                   The second section of the chapter focuses on the
             hypertext literature. It presents a general picture of
             current views of hypertext information systems. Similarly,
             it does not cover specific implementation or technical
             details.


                          Approach to the Literature Search

                   The literature search covered the two distinct areas
             pertinent to establishing a context for the study: 1)
             general information access methodology and 2) basic
             hypertext characteristics.

                   In reviewing the general access topic, the writer
             searched for broad descriptions or characterizations of
             traditional information storage, retrieval, and
             organization approaches.  The monographic literature was
             the chief source for this global view, rather than the
             fragmented approach found in the journal literature.
             Accordingly, the search concentrated upon substantive,
             synthesized works by major contributors and upon topical
             collections.  Review articles and other evaluative
             citations furnished many candidates.  The writer also
             solicited recommendations from dissertation committee
             members about major contributors in the area.

                   Hypertext is still discussed primarily in the journal
             literature.   There are at present few substantial
             monographic treatments.  The writer's examination of the
             published literature confirmed that no major study of
             general organizational approach or information access
             design of hypertext systems has yet appeared.

                   The hypertext topical literature search included
             automated searches of ABI/INFORM, COMPENDEX, Computer
             Select, ERIC, InfoTrac, INSPEC, Library Literature, and
             Science Citation Index.  In addition, the writer made
             extensive manual followup of papers and related citations
             published in the proceedings of Hypertext '87 and Hypertext
             '89, two major conferences on this relatively new area of
             interest.


                      Traditional Information Access Approaches

                   Library science literature concentrates upon the
             objectives and methods of information organization and
             access design.  These questions are after all the central
             concerns of the discipline.  Yet, the culturally and
             pragmatically oriented views of information access are two
             very different approaches to considering the role of
             graphic information storage and retrieval.

                   Reflecting the first approach, Shera (1976)
             <refs 20 20> points out that a culture needs an effective
             medium for the transmission of thought. He feels that the
             various communication media, with an emphasis upon written
             communication, serve as the binding force that shapes
             cultures as a cohesive whole. He postulates that
             communication is the central mechanism linking the cultural
             components which he identifies as: social organization,
             tools (technology), and scholarship. He thus stresses the
             cultural contributions of library and information systems,
             in providing efficient access to recorded information
             (Shera, 1976). Many other major writers similarly emphasize
             the cultural and historic importance of libraries and
             organized information retrieval systems (Johnson and Harris
             1976 <refs -johnson>; Rowley 1987 <refs -rowley>; Foskett
             1982 <refs -foskett>).

                   Writers expressing the second view, the pragmatic or
             practical aspects of information retrieval, do not
             contradict or diminish the cultural role.  Instead, they
             rather emphasize the functionality of information
             retrieval.  Shera himself concedes that the primary
             professional responsibility of the librarian and
             information retrieval specialist is "that of bringing
             recorded knowledge under manageable control" (Shera 1976,
             59) <refs -shera>.

                   There are numerous expressions of the pragmatic view.
             For example, Kent (1971) <refs -kent> notes that the
             utopian objective of an information retrieval system is to
             deliver pertinent information in response to a reasonable
             question. Koenig (1983) <refs -koenig> and Rowley (1987)
             <refs -rowley> concur with this goal-centered view. They
             portray the function of information system design as a
             pragmatic matter of efficient organization and location of
             stored information or knowledge. In Koenig's words, ". . .
             the central thread is knowing how to put information away
             and find it again" (1983, 193).

                   Borko and Bernier point out that knowledge organizing
             methods are central and absolutely necessary to the whole
             operation of our society.  They note that we are so
             accustomed to organizational and information access tools
             that we habitually and unconsciously depend upon them.  The
             authors refer not only to specialized tools like library
             catalogs, indexes, and databases, but also to more prosaic
             information retrieval systems, such as telephone
             directories, school curriculum numbering systems, product
             catalogs, purchase order systems, posted building tenant
             registers, and bus routing tables.  They observe that our
             culture takes such information retrieval mechanisms
             unconsciously and completely for granted, viewing them as
             basic infrastructure for living (Borko and Bernier 1978)
             <refs -borko>.


                         Major Contributors to Traditional
                              Information Access Theory

                   Within the two major schools of thought, several
             distinct approaches to subject access to knowledge have
             been advocated.  Dewey and Cutter were two early and
             important innovators of methods of organizing access to
             recorded information.

                   Dewey is widely known for devising and popularizing
             his Decimal Classification, which remains an important and
             widely used bibliographic organizing system to the present
             day.  He himself noted that although he had produced an
             efficient coding and shelving scheme, it was not at all
             rigidly based in abstract classification theory.  Instead
             it was actually an arbitrary and subjective standard format
             for effectively depicting the organization of knowledge.
             He wrote that he had rejected theory in favor of
             consistency, mnemonic convenience, and practical usefulness
             (Dewey 1885) <refs -dewey>.

                   Dewey successfully presented his classification as a
             foundation and operating standard for pragmatic library
             practice.  He correctly predicted the practical
             efficiencies and benefits to be gained by adherence of many
             libraries to a single, compatible, organizational and
             shelving scheme. These benefits of standardization
             definitely contributed to the widespread adoption of the
             Decimal Classification.  Dewey also provided additional
             advantages by incorporating his classification methodology
             into his formal library school offerings.  Last but not
             least, his considerable personal skills in marketing and
             promoting the classification were important factors in the
             system's success (Sellberg 1988 <refs -sellberg>, Shera 1966
             <refs -shera>).

                   Cutter's 1904 publication Rules for a Dictionary
             Catalog is still considered one of the major expressions of
             the subject classification approach (Shera 1966)
             <refs -shera>. His major contributions, such as uniformity
             in headings, preference for common usage, portrayal of
             knowledge as reflected in the literature, and the principle
             of specific and direct entry, remain important concepts of
             classification to the present time. Cutter's definition of
             classification was demonstrably the major influence upon
             the design of the Library of Congress (LC) Classification
             (Chan, Richmond, and Svenonius 1985) <refs 4 20>. As Dewey
             suggested, the attractions of standardization played a
             large part in the adoption of the LC classification. The LC
             system also became a major classification standard, due in
             large part to the cooperative cataloging economies, and to
             the attractiveness of centralized catalog card publishing
             and distribution. Cutter's approach to subject
             classification is also evident in both the Sears subject
             headings and the Wilson index publications (Foskett 1982
             <refs -foskett>; Rowley 1987 <refs -rowley>).

                   In his work on Systematic Indexing, Kaiser
             contributed the first consistent approach to the order of
             presentation of the aspects of composite subjects (Rowley
             1987) <refs -rowley>. He proposed that the relationships of
             composite subjects should be consistently expressed in the
             order of first Concrete, then Process. Kaiser gave specific
             recommendations for the treatment of complex topics, and
             for handling geographic subdivision or place names. His
             simple concrete-process approach was the basis for many
             modern subject representation systems. Kaiser's system has
             been successively extended by Ranganathan, Coates, and
             Vickery, for the handling of more complex subject
             representations (Foskett 1982) <refs -foskett>.

                   There have been other enumerative classification
             schemes or theories of good quality and theoretical base.
             Those of Bliss and Sayers are good examples (Foskett 1982)
             <refs -foskett>. However, it appears that the acceleration
             of growth and size of recorded knowledge brought an end to
             the development and adoption of the great enumerative
             classification schemes. A main drawback of these massive
             organizational schemes was that they were essentially
             static. Enumerative schemes are simply not able to
             satisfactorily and efficiently reflect the constant shift
             and expansion of modern knowledge (Foskett 1982)
             <refs -foskett>.

                   Enumerative systems contain a basic theoretical
             difficulty: the impossibility of defining consistent
             principles of subdivision in a universal, hierarchical
             classification.  In Britain, after extensive deliberation,
             the Classification Research Group concluded that schemes
             using the enumerative approach were inevitably doomed to
             failure, due to inconsistency and high maintenance expense.
             They finally decided that it was impractical to keep such a
             representation current with the development of modern
             knowledge (Classification Research Group 1985) <refs -group>.

                   Ranganathan's facet analysis concept, expressed in
             the 1930's, was the next major advance in the approach to
             subject classification.  Facet analysis is defined as a
             controlled process by which a document is distilled into
             its component subject aspects or categories.  These aspects
             or facets can then be used to synthesize a classification
             code by stringing together or connecting the class
             identifiers of the basic concepts.  Ranganathan's system
             depends heavily upon punctuation to express the complex
             relationships between the various facet aspects.  This is
             in contrast to enumerative approaches like Dewey and Bliss,
             which are mostly prestructured prior to use (Cleveland and
             Cleveland 1990) <refs -cleveland>.

                   Ranganathan's scheme was in itself an evolutionary
             synthesis, since it carried on or developed concepts
             expressed or suggested by Gesner, Cutter, and even to some
             extent by Dewey (Shera 1966) <refs -shera>. The aspect
             analysis central to Ranganathan's facet approach is
             particularly efficient when combined with mechanized
             manipulation and synthesis. He developed his subject
             classification methods within the traditional, manual
             processing environment. The controlled concept vocabulary
             and the standardized methods for aspect and relationship
             representation were intended to produce synthesized
             classification coding strings. These synthesized strings
             were then to be used for production of printed catalog
             listings or indexes, and for document collection
             arrangement.

                   However, the "decomposition" effect of facet analysis
             is also a pragmatic and economical approach for description
             or representation of document content, using a controlled
             collection of concept terms (Chan, Richmond, and Svenonius
             1985) <refs 4 20>. Shera points out that the aspect
             analysis approach has so far proved to be the most
             efficient for mechanized information retrieval. He observes
             that limitations in the creation and use of the overly
             complex synthesized facet codings have been evaded or
             sidestepped by the advantages of machine search and
             manipulation efficiencies (Shera 1966) <refs -shera>.

                   Ranganathan's facet identification approach was also
             complimentary to the ideas of one of the pioneers of the
             computerized retrieval approach.  Taube introduced the use
             of "descriptor" indexing, which is similar to the facet
             concept of subject component representation.  But instead
             of using the subject descriptors to synthesize
             classification expressions, Taube specifically intended
             them to be used for computer searching and manipulation.
             He saw and championed the potential of Boolean logic in
             postcoordinate searching, and of computer processing and
             manipulation for bibliographic processing (Taube 1985)
             <refs -taube>.

                   Taube's early proposals centered on the use of simple
             "Uniterm" descriptors.  These were single terms for
             expressing subject content which were to be directly
             extracted from source document text.  He originally
             advocated the exclusive use of simple term extraction to
             build vocabularies of single terms.  He did not include the
             use of vocabulary control methods.  However, Taube soon
             found it necessary to adopt vocabulary control methods,
             like rules for syntax and control of synonyms.  These
             measures included pre-coordinated or multiple-word terms,
             to better express complex concepts, and to give indication
             of relationships (Foskett 1982) <refs -foskett>.

                   Taube made early demonstration of the potential power
             of computerized retrieval.  His experience showed the
             advisability of combining the effectiveness of controlled
             vocabulary with the efficiency and synthesizing power of
             Boolean post-coordinate retrieval.  His innovations led
             directly to the current mainstream approaches employing
             bibliographic and text information retrieval.   He also
             clearly identified the synergistic effects to be gained
             from machine manipulation of bibliographic information:

                 The system of bibliographic coordination has three
                 major advantages over the systems of classifying and
                 indexing.  In the first place, a system of
                 bibliographic coordination is designed for machine
                 sorting and collating. . . . Secondly, once the
                 categories have been determined, the actual indexing of
                 material in any particular field would be very simple.
                 . . . Finally, the system of bibliographic coordination
                 would, if properly set up, disclose to the searcher
                 more information than had been put into the system.
                 Similarly, in the system of bibliographic coordination,
                 by combining various categories, we may get information
                 which, although implicit in the system, was never
                 explicitly recognized. (Taube 1985, 123) <refs -taube>

                    Text string manipulation has been another major
             approach in modern subject access techniques, since the
             advent of automated processing.  String manipulation uses
             automated processing of titles, descriptions, and subject
             codings, to produce multiple versions or permutations of
             the subject term or aspect identifiers.  The primary
             leverage of string manipulation in subject access
             application is gained by taking advantage of the power and
             economy of computer processing.

                   Luhn directed the first major implementation using
             string manipulation of document titles.  His system
             produced permuted index listings of titles in KeyWord In
             Context (KWIC) format (Luhn 1985) <refs -luhn>. His KWIC
             indexes were printed alphabetical listings, with
             substantive or sorting words listed down the center of the
             printed index lines, for easy recognition. The context of
             the word's occurrence was printed on either side of the
             word, in order to communicate the document title context.
             Titles were "wrapped" or rotated, as needed, so the context
             would fill the line, with the subject word remaining in the
             center position.

                   Luhn admitted this to be an imperfect approach to
             subject identification or representation.  It ignored such
             problems as vocabulary consistency, synonymy, and homonymy.
             It depended completely upon the author's skill and desire
             to effectively express his or her topic in the document
             title.  But he also pointed out that KWIC indexing
             eliminated the substantial investment necessary for
             traditional manual indexing operations.

                   Luhn advocated this indexing method as a fast, cost-
             effective, approach for communication of the content of
             technical literature.  He in fact portayed it as leaning
             substantially towards the goals of technical literature
             communication or distribution, rather than functioning
             primarily as an information retrieval tool (Luhn 1985)
             <refs -luhn>.

                   Responding to information science's penchant for
             devising systems for "automatic subject content analysis,"
             Cleverdon (1985) <refs -cleverdon> has stated that
             conceptual indexing can not be entirely avoided. In this
             respect, he points out, KWIC indexing does not really avoid
             the necessity for conceptual indexing, it merely delegates
             the task to the original author of the document.

                   As a final expression of his facet theory,
             Ranganathan devised the Colon Classification, a complex
             methodology for synthesis, or construction, of subject
             classifications.  Separate facet codes were concatenated,
             using strict and complicated sequencing and punctuation
             rules.  These constructed codes could accurately portray
             the complex relationships of the component aspects.
             However, in both construction and interpretation, the
             complex, dense, code strings were quite difficult to
             comprehend.  It later became evident that the complex
             sequencing and construction logic could be automated.
             System designers could thus make use of computer assistance
             to make human classifier operations easier and more
             efficient.

                   To this end, the Classification Research Group (CRG)
             undertook detailed consideration of various approaches for
             document analysis and access during the 1950s and 1960s.
             They correctly anticipated wide application of automation
             for indexing purposes.  As noted, they decided to
             incorporate the facet analysis approach at an early point
             in their investigations (Foskett 1982) <refs -foskett>.

                   In the late 1960s, Austin directed the creation of
             what became the PRECIS classification system, using the
             CRG's preferred facet approach.  From the start, PRECIS was
             a highly practical project, since it was intended to be
             used for production of the printed British National
             Bibliography.  The PRECIS system successfully incorporated
             facet analysis and controlled vocabulary approaches.  It
             included representation of relational, hierarchical, and
             geographic identification, for accurate communication of
             complex concept relationships.  The final computerized
             implementations efficiently produced the constructed
             strings.  The basic strings were then automatically
             permuted or "rotated" into multiple likely forms, for
             filing in printed index listings (Austin and Digger,
             1977) <refs -austin>.

                   Citation indexing is the contemporary subject access
             approach bearing perhaps the strongest relationship to the
             hypertext approach.  Citation indexes are lists of
             documents, with a sublist under each item of subsequently
             published papers that cite or refer to the indexed item
             (Garfield 1985) <refs -garfield>. As Cleveland and
             Cleveland have observed, "The premise of citation indexing
             is that citations reflect document content, and that an
             author's citations can therefore be substituted for the
             judgment of indexers" (1990, 72) <refs -cleveland>. The
             citation index is therefore a perfect reflection of the
             internal structure of the domain literature.

                   Although other factors should be considered in
             evaluating this index type, the citation index has been
             widely accepted and adopted by end users.  Many of them
             prefer citation indexes over more traditional bibliographic
             research tools.  In more traditional index approaches, a
             researcher must first make the unfamiliar and demanding
             mental effort of exactly defining his or her informational
             needs.  These must then be translated into the format
             vocabulary and syntax of the particular information access
             system.  The need for this whole process may be viewed as a
             substantial obstacle to index use, since end users are
             unused and unskilled in expressing subject or information
             need concepts in formal access vocabulary terms.

                   On the contrary, citation indexes are easily
             approachable by end users.  They can use the obvious and
             easy entry point of "a document or author of known
             interest."  Citation indexes are accordingly quite popular
             with end users within many disciplines.  This user
             preference is similar to the oft-expressed preference for
             hypertext use (Nielsen 1990) <refs 18 20>. This natural
             human preference for the course of least resistance has
             been expressed by Zipf (1972) <refs -zipf> as the Principle
             of Least Effort. Bjrklund (1990a) <refs 2 21> similarly
             cites Krikelas as noting the tendency of information
             seekers to specifically base their search activities upon
             some concept of minimum personal effort.

                   Printed citation indexes would appear to be similar
             to the hypertext associative approach.  Much like
             hypertext, citation indexes capitalize upon user
             recognition of topical relevance, using context or example.
             Colloquially phrased, both approaches capitalize upon the
             user's "I knows it when I sees it" recognition of
             relevance.  They also both avoid the mental strain of the
             user needing to learn how to deal with the information
             retrieval system.

                   In the same way that footnotes within a document
             contain the author's judgment of what documents are
             relevant to his or her topic, the embedded links within an
             authored hypertext document contain the same sort of
             relevance judgment.  The links are clearly visible, in this
             case, as a suggestion for the nearly effortless hypertext
             associative retrieval commands.


                            Subject Access Overview Works

                   Broad overviews of the subject access topic appear in
             both works giving an introduction or basic survey, as well
             as in works taking reflective or philosophical views.  A
             systems analysis or engineering orientation has also
             emerged in recent years.

                   Borko and Bernier (1978) <refs -borko>, Rowley (1987)
             <refs -rowley>, and Cleveland and Cleveland (1990)
             <refs -cleveland> are basic introductions to indexing and
             abstracting. All three books offer an historical view of
             subject indexing development, of the various approaches to
             and types of indexing, and of practical indexing
             operations.

                   Metcalfe (1957) <refs -metcalfe> offers a
             theoretical, reflective, and highly personal approach to
             subject access practice. He presents detailed historical
             review of the evolution of subject representation in
             indexing and classification. There is extensive analysis of
             minute developments and changes in the approaches of the
             major figures. Writing in 1957, he covers only the earliest
             ventures into "mechanical retrieval," including Taube's
             "Uniterm," Mooer's "Zatocoding," and Shaw's "Rapid
             Selector." But the detailed analysis of these early systems
             can certainly be of interest to modern readers.

                   Metcalfe examines the metaphysics, logic, and
             philosophical approaches of the major cataloguing and
             classification figures.  He is highly critical of
             classified approaches to cataloging and indexing, including
             Ranganathan's analytico-synthetic approach (Foskett 1982)
             <refs -foskett>. He blames much of the weakness of British
             bibliographic tools, compared to American products, to the
             British adherence to classified approaches. Metcalfe's book
             is a highly readable and informative one, useful to those
             wishing to examine the origins and evolution of modern
             subject access approaches.

                   Foskett (1982) <refs -foskett> presents a balanced
             overview of subject access theory and historical
             development, comparable in scope to Metcalfe's coverage. He
             operates from the basic social or cultural view of the
             library role, as the information transfer agency.

                   He distinguishes knowledge and information as
             follows: "knowledge is what I know[,] information is what
             we know." (1982, 1) He then expresses the view of libraries
             as a fundamental link in the chain of communication of
             knowledge:

                 . . . society began to move forward when information of
                 various kinds began to be recorded in relatively
                 permanent forms which could serve as substitute for the
                 wise man in person. Knowledge only becomes generally
                 useful when it is made available; by recording it, we
                 do our best to ensure that it is permanently available
                 to anyone who may need it, instead of ephemeral and
                 limited to one individual. (1)

                   Foskett bases his presentation upon this need for
             effective communication of information.  His book is
             important in its coverage of the historical and theoretical
             bases for subject access systems.  It deals with the
             development of information retrieval automation, methods of
             information systems design, and quantitative systems of
             evaluation.  His treatment, however, emphasizes the goal of
             human communication, not the purely mechanistic or
             technical view of systems design.  Foskett uses a wide
             combination of approaches to give a comprehensive and
             balanced view of the topic.

                   Several other writers concentrate more on the systems
             analysis style of approach. For instance, Meadow (1973)
             <refs -meadow> gives a clearly stated and logical view of
             information retrieval systems. His treatment arises very
             much from the systems viewpoint and from the Shannon and
             Weaver communications model (Shannon and Weaver 1959)
             <refs -shannon>. This early communications model reflected
             a technical, "effective transmission" view, rather than a
             social communication function.

                   Meadow summarizes the problems of indexing and
             subject representation and describes the necessity for
             formalized index language solutions.  His is a capable, but
             rather task-oriented treatment.  As he himself
             straightforwardly phrases it, ". . . information retrieval
             means the retrieval of information-bearing symbols from a
             file, and is independent of the nature or form of the
             information retrieved or the use to be made of it" (1973,
             120).

                   Vickery (1987) <refs -vickery> presents a view of
             information sciences as related to communication in
             society. It is also more of a descriptive, objective view,
             without the "wisdom-centeredness" characterized in
             Foskett's presentation. Vickery is firmly within the
             tradition of alphabetical indexing theory, but he has not
             chosen to emphasize subject access theory in this work. It
             is rather a broad treatment of the entire area of
             information science. He does, however, briefly note the
             research or theoretical traditions of subject access,
             characterizing them into four main themes. He describes
             these as: the structure of classifications; the tradition
             of alphabetical indexing; the interpretation of
             classifications and indexes as retrieval languages; and the
             newer approaches arising from the computerization of
             information.

                   Another group of writers expresses a highly pragmatic
             or "engineering problem" approach. Milstead (1984)
             <refs -milstead> capably presents the historical basis for
             subject access system approaches, but she emphasizes the
             system design aspects of the question. She depicts the
             system design problem as a set of interacting choices,
             describing the ways in which one choice may constrain
             others. (1984, 5) She sympathizes with the human purposes
             for knowledge access, but she defines primary goals very
             objectively, as follows:

                   1) minimize total time and effort to find answers;
                   2) minimize redundant content; and
                   3) minimize the number of lookups. (17)

                   Milstead effectively presents her problem-centered
             viewpoint.  She describes the design of a subject access
             system not only as a subjective or theoretical exercise,
             but also as a practical exercise in cost-effectiveness.  In
             her view, the efficacy of a final design is highly
             dependent upon the wise selection of trade-offs.

                   In another pragmatic viewpoint of information system
             planning, Taylor (1986) <refs -taylor> presents his
             "value-added model" of information systems. This approach
             analyzes the values an information system delivers to
             users. The model does not address the specific details of
             subject access approaches. It rather attempts to define the
             values that users find to be important in selecting
             information systems. Taylor generalizes the value-adding
             activities of the systems as:

                 1) selecting input;
                 2) storing and organizing for physical access;
                 3) describing and labeling for retrieval;
                 4) analyzing, evaluating, and comparing for quality;
                 5) combining and interpreting;
                 6) responding and adapting to specific user problems.
                 (1986, 202)

                   The results of many of the activities will of course
             be dependent upon the success of the document
             representation and delivery mechanisms.  In Taylor's
             phrasing of the required operations, the system:

                 * displays its contents, either in menu/instruction
                 form or in text as direct response to a query;
                 * transmits signals concerning the potential value of
                 portions of its contents;
                 * provides a variety of means to aid the user in making
                 choices. (1986, 54)

                   Although these are very generally stated goals, they
             are obviously specifically applicable to the design of a
             good subject access system.  Taylor's treatment is thought-
             provoking, and may be applied to a computerized library
             catalog, an online fulltext database, or a hypertext
             system.  It is a well-reasoned approach to answering the
             aforementioned "what are we trying to do here?" question.

                             Hypertext System Background

                   This section will identify important early
             implementations using hypertext information system
             approaches.  It will also cover general hypertext
             background.  The review will not attempt to cover technical
             details, nor details of specific implementations, but will
             instead concentrate upon hypertext system concepts
             pertinent to this paper.  The section will therefore not
             reflect the common literature emphasis upon hypertext
             technology.


                               Historical Development

                   As mentioned in the introduction, Bush initially
             proposed the hypertext concept in 1945.  However, except
             for his imaginative vision, there was no substantial
             progress until the 1960s.  Engelbart's NLS/Augment project
             began at Stanford in 1962, including components of office
             automation, text processing, and hypertext, and was
             publicly demonstrated in 1968 (Engelbart, 1988)
             <refs -engelbart>. The Augment system, later marketed by
             McDonnell-Douglas, has supported a group of over 1000
             knowledge workers for over twenty years (Horn 1989)
             <refs -horn>.

                   Nelson, coiner of the term "hypertext," was an early
             hypertext visionary and promoter of an ambitious global
             network hypertext system concept called Xanadu. This is
             conceived as a distributed network of back end local
             hypertext databases (Nelson 1974) <refs 18 17>. Nelson
             proposes a repository system to hold everything ever
             written, and being written, with intricate hypertext
             connections between all related documents. Xanadu is now
             supported by the substantial resources of the Autodesk
             software company. The Xanadu product has not been released
             at the time of this writing, although Nelson predicts it
             will be made available during 1991 (Ditlea, 1990)
             <refs -ditlea>.

                   Andries van Dam directed the next major hypertext
             system activity, beginning in 1967 at Brown University.
             The Hypertext Editing System was the world's first
             operational hypertext system, and was eventually installed
             at the Houston Manned Spacecraft Center.  In 1968, van Dam
             then implemented the File Retrieval and Editing System
             (FRESS) hypertext system at Brown University (Nielsen,
             1990) <refs 18 20>.

                   Brown University remains a major center in hypertext
             system development, with its Intermedia hypertext
             implementation.  This system is a highly integrated system,
             with editing, calculating, text searching, dictionary
             consultation, graphic/animation, and hypertext abilities.
             It is used as a general teaching and learning environment,
             in curriculum support, for individual communication and as
             a channel for collaboration (Yankelovitch, 1985)
             <refs 25 7>.

                   The University of Maryland has also been active in
             hypertext system research and development.  Shneiderman
             implemented the TIES (The Interactive Encyclopedia System)
             project at this university in the early 1980s.  The system
             has since been renamed to Hyperties (Shneiderman, 1987b)
             <refs 21 4>. Shneiderman is active in the research areas of
             software psychology and user interface research. As a
             result, there has been much investigation in these
             particular areas of the hypertext system investigations at
             the University of Maryland.

                   Microelectronics and Computer Technology Corporation
             (MCC), the American computer technology research
             consortium, has been another major hypertext research
             center.  Conklin and Begeman have reported upon the "gIBIS"
             system developed at MCC.  (The system acronym is derived
             from "graphic, issue-based information system.")  gIBIS is
             a networked hypertext system designed primarily for the
             coordination, tracking, and facilitation of software
             development projects.  The hypertext network was designed
             as a system to identify issues, enhance communication, and
             track issue resolution, for large software development
             teams with software personnel that may number in the
             hundreds (Conklin and Begeman 1989) <refs 6 4>.


                       Hypertext Overviews and Bibliographies

                   Conklin (1987) <refs 6 1> published the earliest
             comprehensive and definitive piece on hypertext. He
             described system concepts, types and subtypes of hypertext
             link mechanisms, characterized the variety of system
             approaches, and surveyed existing implementations. His type
             description may be paraphrased as:

                 * Macro literary systems, large online libraries, of
                 the Xanadu model;
                 * Problem exploration tools, for personal and group
                 problem exploration, outlining, authoring, and design;
                 * General hypertext technology, general purpose
                 hypertext implementations, for experimentation and
                 innovation;
                 * Structured browsing systems, designed for mass user
                 information systems, information retrieval and
                 dissemination, and electronic publication.

                   This paper is most concerned with the final category
             mentioned above.  "Structured browsing systems" will be the
             basis for "publication" systems, for mass market and
             vertical market information distribution.  As such, they
             must incorporate highly effective information retrieval
             methods.  The systems will need to simultaneously provide
             both power user sophistication and simplicity of use for
             absolute novices.

                   Conklin also described the "lost in space"
             phenomenon, the hypertext system problem most commonly
             mentioned by writers.  This confusion of orientation or
             location is caused by the chaotic maze of linked network
             nodes often presented to the user in a poorly designed
             hypertext system.  This creates "potential for the user to
             become lost or disoriented" (1987, 38) <refs 6 1>. As a
             computer professional, Conklin perhaps predictably
             suggested technological solutions. First, he recommended
             "graphic browsers," or pictorial or diagrammatic
             representations of local or global link connections;
             second, he suggested improvements in keyword or text
             search.

                   Fiderio (1988) <refs -fiderio> offered another
             comprehensive introduction to hypertext, more generally
             directed, and much less technical than the Conklin
             overview. Shneiderman and Kearsley (1988) <refs 21 16>,
             and Jonassen (1989) <refs 15 2> also contributed
             popularized book-length introductions to the hypertext
             topic.

                    Barrett, Berk and Devlin, Horn, and Martin have
             produced works concentrating upon the "editorial
             management" of hypertext, covering implementation or
             production of hypertext information systems.  Barrett's
             book collected contributions from active investigators and
             developers of hypertext systems, describing practical
             experience, and identifying problems in production and
             design (Barrett 1989) <refs 2 7>. Horn and Martin presented
             detailed guides to structured, efficient, hypertext design
             and production management (Horn 1989 <refs -horn>, Martin
             1990) <refs 17 12>. Berk and Devlin compiled a substantial
             reference guide to the design and implementation of
             hypertext systems, with contributions by many highly
             regarded hypertext developers and authors. Their work
             includes chapters on editorial design and authoring tools,
             production details, legal issues, and case studies (Berk
             and Devlin 1991) <refs -berk>.

                   Hypertext '87 and Hypertext '89 are proceedings of
             two major conferences on the topic, sponsored by the
             Association for Computing Machinery (ACM). They are major
             collections of papers on the subject, with
             multidisciplinary approaches (Association for Computing
             Machinery 1987 <refs 1 11>, 1989 <refs 1 16>). These
             proceedings were substantial early collections of papers,
             serving to centralize work on the topic in the absence of
             monographs during this period.

                   Trigg and Lin have produced dissertations on
             hypertext. Trigg's early work (1983) <refs -trigg> was
             probably the first dissertation on the topic of hypertext.
             He described the TEXTNET system, used for online scientifc
             document and information sharing. Lin (1989) <refs 16 18>
             addressed the question of providing multiple metaphors for
             hypertext information access. As in most other hypertext
             research, the term "metaphor" was here applied to the
             general concept of presentation interface. Lin's
             investigation utilized a tourist information system, with
             presentation of information via book, note card, and map
             interface metaphors.

                   In contrast to Lin's study, this paper does not focus
             on presentation metaphors.  It is concerned rather with
             hypertext incorporation of formal or traditional
             information access presentation methods, such as indexing,
             hierarchical classification, or string-searching
             approaches.

                   Nielsen (1990) <refs 18 20> offers the most
             comprehensive book treatment of the topic. In it, he offers
             detailed coverage of historical background, implementation
             descriptions, applications, system architecture, usability,
             evaluations, and predictions for future development of
             hypertext. In his book, Nielsen provides a selective
             annotated bibliography, of high quality. Knee and Atkinson
             (1990) <refs -knee> have also produced a comprehensive,
             book-length, annotated bibliography on the hypertext system
             topic. The two works together offer substantial
             bibliographic resources on the topic.


                        Educational Applications of Hypertext

                   There has been considerable literature on the
             educational applications of hypertext system. These have
             ranged from lower schools to university levels (Beck and
             Spicer 1988 <refs -spicer>; Chignell and Lacy 1988
             <refs -chignell>; Crane and Mylonas 1988 <refs -crane,>,
             Smith 1988 <refs 21 21>; Underwood 1988 <refs -underwood>;
             Jonassen 1986 <refs 14 22>, 1989 <refs 15 2>; Marchionini
             1988 <refs -marchion>; Yankelovitch, Landow and Cody 1987
             <refs 25 3>). Many of these writers stress the advantages
             of the connectivity of knowledge and the effectiveness of
             the learner-driven presentation of information.

                   Locatis (1987) <refs -locatis> notes the
             attractiveness of this self- directed educational approach:

                 Each display in the knowledge base functions as a
                 'menu' to other displays, and contains cues to
                 additional information available. . . .  [Learners can]
                 mark displays for later retrieval, for referencing
                 personal notes, or for evoking searches. (1987, 94)

                   He summarizes the advantages and integrative aspects
             of hypertext for educational applications.  His list
             includes: storage capacity, integrated media capability,
             interlinking of information systems, and fast information
             retrieval.

                   Most cited writers do not consider information
             organization or structure in depth, but instead focus upon
             specific hypertext authoring styles.  They usually
             recommend a structured or hierarchical approach, but there
             is generally no depth of treatment of how to best achieve
             this.  Instead, most writers appear captivated by the
             flexibility of hypertext linking and the resulting fluidity
             of style afforded to the author.

                   The apparent subjective lure of hypertext systems has
             affected educational implementations at all levels. The
             Brown University Intermedia system (Yankelovitch et al.
             1988) <refs 24 22>, and the University of Southern
             California's Project Jefferson (Chignell and Lacy 1988
             <refs -chignell>; Kinnell 1989 <refs -kinnell>) are
             advanced investigations and implementations of hypertext
             technology for academic and research infrastructure
             purposes. The various reports on these two projects discuss
             the interdepartmental and library cooperation in designing
             the system, and the emphasis upon integration into the
             teaching curriculum. In both applications, the educational
             and writing tool priorities appear to have overshadowed the
             information access elements.


                          Importance of the User Interface

                  The "user interface" is a basic concern of computer
             and information system designers, with much justification.
             The user interface is the meeting place of users and
             computer systems; "where the rubber meets the road," so to
             speak.  Flaws or mistakes in human factors design or in
             effective communication of system messages will have
             substantial negative effects upon system usability and
             performance.  Computer professionals realize this.  They
             consider the computer-human interface so important that
             managers now routinely devote as much as one-half or more
             of total software project cost to user interface design
             efforts (Baecker and Buxton 1987) <refs -baecker>.

                   Study and design of the "computer-human interface" is
             presently an active interest area.  Reflecting this, the
             Special Interest Group on the Computer-Human Interface
             (SIGCHI) is a sizable and active group within the
             Association for Computing Machinery.  The multi-
             disciplinary concerns have drawn much attention and
             participation from a number of peripheral specialties.

                   Much literature directly addresses computer-human
             interface issues. Baecker and Buxton (1987) <refs -baecker>
             have produced a substantial introductory collection
             illustrating the breadth of multi-disciplinary concerns
             relating to human interface design. They have compiled a
             wide selection of primary source texts, arranged in topical
             chapters, which results in an excellent introduction to the
             topic. Helander (1988) <refs -helander> edited a
             comprehensive handbook on the topic of human-computer
             interaction, with contributions from a number of approaches
             from a number of disciplines. Shneiderman and Brown have
             published highly-regarded standard works on design for the
             human interface (Shneiderman 1987a <refs 20 24>; Brown 1988
             <refs 4 7>).

                   Galitz has produced a handbook specifically covering
             display screen design. He reviews research showing that
             interface design features can make as much as 20%
             difference in human processing speed, interpretation, and
             errors. This will obviously have significant effects on
             long-term costs relating to usage, accuracy, and labor
             (Galitz 1989) <refs -galitz>. Dumas (1988) <refs -dumas>
             also thoroughly covers user interface design. He presents
             detailed information on transaction control, data entry,
             screen presentation, and other topics. Dumas advises on
             management of the interface design project.

                   Ravden and Johnson (1989) <refs -ravden> offer a
             practical guidebook to evaluation of the human-computer
             interface, stressing usability and accuracy. Their
             guidebook gives a specific checklist approach, along with
             detailed recommendations for planning, execution, and
             analysis of the evaluation.

                   As well as clear textual communication and good
             conceptual metaphors, professionalism in graphic design is
             critical to interface effectiveness.  Faiola emphasizes the
             need for involving skilled graphic technologists in
             computer system design, and includes a comprehensive visual
             design bibliography (1988) <refs -faiola>.

                   Referring specifically to hypermedia, Vainio-Larsson
             (1986) <refs -vainio> expresses the importance of the
             critical human interface point. His comments may be
             extended to software in general. He points out that the
             user must be able to quickly establish conceptual
             understanding of the system behavior and actions, in order
             to attain effective interaction. He describes system/human
             communication is a "top-down hierarchy," with the user at
             the top of the hierarchy, communicating via the user
             interface, to the application. Vainio-Larsson describes a
             good interface as functioning to shield the user from
             "implementation close" interactions. This means the user is
             protected from the necessity of communicating in
             computer-type language. Hutchins, Holland, and Norman
             (1986) <refs -hutchins> similarly portray the interface as
             the user's tool for dealing with the immense distance, or
             "gulf of execution," between the user, the system internal
             operations, and the system goals.

                   Library and information science professionals are
             quite aware of the importance of the user interface.  There
             have been several literature reviews within the library and
             information science literature, dealing with psychological
             and human factors interface research (Borgman 1984
             <refs -borgman>; Ramsey and Grimes 1986 <refs -ramsey>).


                                Hypertext Performance

                   Researchers are demonstrating that hypertext systems
             can offer information retrieval and task performance
             advantages.  As suggested in the preceding section,
             researchers are also finding that interface design
             significantly impacts upon hypertext system performance.

                   Egan and his fellow Bellcore researchers have shown
             in a number of investigations that subjects using their
             SuperBook hypertext system as an information retrieval and
             research aid achieved substantially higher performance than
             subjects using equivalent printed sources.  They concluded,
             "Students using SuperBook answered more search questions
             correctly, wrote higher quality 'open book' essays, and
             recalled certain incidental information better than
             students using the conventional text"  (Egan et al.
             Behavioral Evaluation. 1989, 205) <refs 8 1>.

                   The Bellcore team used the "iterative implementation"
             system design approach.  Each evaluation of the hypertext
             system was followed by incremental improvements, each level
             being treated as a prototype for the succeeding version.
             Improvements in the three versions of the system, directed
             mainly to streamlining the interface, produced substantial
             performance gains at each level.  The final, optimized,
             "MiteyBook" version especially demonstrated the performance
             gains from interface improvement.  This version delivered
             25% better performance than the printed book version, and
             was significantly faster than SuperBook II (Egan et al.
             Formative Design Evaluation. 1989 <refs 7 20>; Egan et al.
             Behavioral Evaluation. 1989 <refs 8 1>; Egan et al. 1991
             <refs 8 9>).

                   The United States Army Research Institute conducted
             an evaluation of the Personal Electronic Aid for
             Maintenance (PEAM) system in 1987 (Wisher and Kincaid
             1988) <refs -wisher>. The research team evaluated a
             hypertext-based electronic delivery system used for
             technical manual data. The study involved observation of
             fourteen Army technicians and fifty-six Navy technicians,
             performing troubleshooting and repair for a total of 610
             hours. Army and Navy technicians worked on M1 tank turrets
             and Sparrow missles, respectively.

                   PEAM users showed an 11:1 advantage in
             troubleshooting error rate, and a 2:1 advantage in repair
             error rate.  The Navy technicians using PEAM had a 25% time
             reduction over test subjects using equivalent printed
             technical manuals.  The Army technicians using the PEAM
             system performed approximately 14% slower than the group
             with printed manuals.  The difference was traceable
             specifically to an implementation version differing from
             the Navy version only in that it had longer graphic display
             times (greater than or equal to fifteen seconds for image
             retrieval).  This research demonstrates the surprising
             cumulative performance effect resulting from a single,
             seemingly trivial, interface issue.

                   Choice of the effective presentation "metaphor" is
             also an important interface issue.  Two major studies have
             addressed this specific question in relation to hypertext
             systems. Lin (1989) <refs 16 18> studied multiple
             navigation metaphors within a hypertext implementation. She
             found that subjects using a single metaphor were most
             effective in tasks that were suited to the type of
             exploration afforded by the particular metaphor model. She
             also found that subjects using multiple metaphors had
             longer learning curves in achieving effective performance,
             due to the necessity of learning more navigation
             approaches. However, as experience increased, users with
             multiple navigational metaphors available to them began to
             show a performance advantage.

                   Hammond and Allinson (1988a <refs 11 18>, 1988b
             <refs 11 23>, 1989 <refs 12 5>) also studied use of
             multiple hypertext navigation metaphors. Their study used a
             small hypertext system with thirty-nine screens containing
             information about the history of York, England. Available
             metaphors included base hypertext links only (H), a Map
             facility (M), an Index facility (I), and a guided Tour
             facility (T). They used five study groups, one using base
             hypertext only (H); three using base hypertext and one
             other facility (HM, HI, and HT); and the last using all
             hypertext navigation facilities (HMIT).

                   The investigators found that all groups performed
             similarly on testing, with no significant differences.  But
             a surprising result emerged:  the groups saw different
             numbers of screens.  There were mean scores of 18.1, 20.3,
             18.8, 19.9, and 17.7 screens viewed, by H, HM, HI, HT, and
             HMIT respectively.  Since there was no significant
             difference in performance, the subjects seeing the least
             information screens tended to extract more information from
             them.  They thus performed or scored more efficiently than
             those who saw more screens (1989, 200) <refs 12 5>. The
             investigators generalized that the subjects with more
             hypertext navigation tools available for use tended to
             perform most efficiently in information retrieval tasks.


                         Authoring and Organizational Issues

                   The problems of the simplistic, intuitive, approach
             to hypertext system building are obvious.  Illustrative of
             the problem, Nielsen summarized the results of a field
             study observing users of a "small" Guide hypertext document
             "which could be read in one hour."  He reports that even
             with this small hyperdocument, more than half of the users
             agreed with the statement, ". . . I was often confused
             about where I was" (Nielsen 1990, p. 127) <refs 18 20>.

                   In his keynote address for the ACM "Hypertext '87"
             conference, van Dam covered nine key areas "we all ought to
             be looking at."  Numbers five and seven respectively were
             the need for improvements in "hyperspace" navigation and
             the need for better organizing, indexing, and accessing the
             hypertext knowledge bases (van Dam 1988, 894-895)
             <refs -van dam>.

                   In a chapter on the topic of authoring hypertext,
             Shneiderman cautions that "there is a real danger that
             [authoring] can also lead to hyperchaos.  He points out
             dual dangers: 1) that hypertext may be inappropriate for
             some projects, and 2) that the design of the hypertext may
             be poor (e.g., too many links, confusing structure)"
             (Shneiderman 1989, 116) <refs 21 10>. He advises control
             measures, which may be viewed as versions of standard
             library or indexing operation control methods. His
             suggestions included: starting with a meaningful overall
             structure concept; consistent naming of documents/nodes;
             maintaining a master reference/control list; and verifying
             the existence of nodes named in link references, to avoid
             blind references (1989, 125) <refs 21 10>.

                   Reporting on the three teams that translated the
             Hypertext '87 conference proceedings into their respective
             hypertext products, Alschuler comments on the inconsistency
             of implementation, the poor indexing, the disorganization
             of index lists, and the production team reports of extreme
             difficulties.  Elise Yoder, working with the "KMS"
             hypertext product, told her that it was simply not possible
             to connect everything as thoroughly and effectively as they
             had intended.  "By the end of the project, in [Yoder's]
             words, they were 'practically fabricating' meaningful
             connections in order to install more links" (Alshuler 1989,
             358) <refs 1 5>.

                   Shneiderman, of the Hyperties version authoring team,
             reported to her that the task "confirmed his suspicion that
             this type of 'linear' text could not be translated into
             hypertext" (358). These individuals were all experienced
             hypertext system implementers, working on a relative small
             knowledge base (The full printed conference proceedings
             occupy only 432 pages, plus index).  Alschuler muses:

                 Was this poor showing due to sloppy, hurried
                 construction rather than the fundamental limitations of
                 the programs?  Each group had a team of two or three
                 people and reported spending approximately two months
                 preparing the hypertext publication. . . . [I]t would
                 be impossible to find . . . more qualified individuals
                 than those responsible for the applications. . . .  It
                 does not seem likely that lack of development time or
                 talent was an issue. (1989, 358)

                   Alschuler's concern over this apparent paradox is
             understandable.  The writer has prepared a subjective
             response to this question, which appears in Chapter V of
             this study.


                              The Engineering Approach

                   In contrast to the intuitive or subjective
             approaches, there are reports of standardized, methodical,
             and generally successful approaches to hypertext system
             creation or conversion.

                   Most of these have been for commercial or
             institutional publishing purposes, and were based on a
             task-oriented, engineering outlook. Raymond and Tompa
             (1988) <refs 19 21> have reported on the conversion task
             and analysis needed for the monumental translation of the
             Oxford English Dictionary into a CD-ROM hypertext format.
             Frisse (1988b) <refs 9 17> covered the planning and task
             execution for the hypertext conversion of the Washington
             University Manual of Medical Therapeutics, a 500 page
             institutional guide for internal medicine standard
             practice. Glushko (1989 <refs 10 21>, 1990 <refs 11 2>)
             described the conversion of the 3000-page Engineering Data
             Compendium into a hypertext CD-ROM.

                   There are also several book-length guides to this
             more structured or disciplined hypertext system-building
             approach. Information systems consultant James Martin has
             published Hyperdocuments & How to Create Them, a detailed
             guide for developing effective electronic hypertext
             document systems (1990) <refs 17 12>. He proposes a
             basically hierarchical structure planning approach,
             stressing the creation of clear, consistent trails. As does
             Frisse (1988a) <refs -frisse>, Martin proposes the
             application of outlining software tools as an aid to
             definition and structual maintenance of consistent
             hierarchical hypertext structures. Martin deals extensively
             with authoring project management, covering printed text
             conversion, authoring team management, incorporation of
             graphics, methods of ongoing database management, and other
             important production topics.

                   Similarly, Horn (1989) <refs -horn> has adapted
             "Information Mapping," his structured technical writing
             methodology into a hypertext authoring approach. His
             approach is also based on highly structured hierarchical
             design. Similar to Martin's methodical approach, Horn
             thoroughly covers the spectrum of hypertext information
             system design and management. His presentation focuses on
             the authoring and stylistic tasks, but does not cover the
             general production topics in detail, as does Martin.

                   Neil Larson, the developer of the MaxThink hypertext
             authoring system, the subject of this case study, also
             stresses the hierarchical authoring approach (1987a
             <refs 15 24>, 1987b <refs 16 4>, 1988 <refs 16 7>, 1989
             <refs 16 10>, 1990 <refs 16 14>). In fact, his company's
             first software product was "MaxThink," an award-winning
             outliner program, which later became one of the
             cornerstones of the hypertext authoring system. He
             subsequently produced "Houdini," a more advanced matrix
             (three-dimensional) outliner program. The matrix outliner
             is capable of building highly complex network outlines, in
             which any topic or node can be connected to any other node.
             The application to effective hypertext system building is
             obvious.

                   For example, Larson's associate Tony Phillips
             currently uses the MaxThink system in authoring the DaTa
             hypertext.  This is a CD-ROM hypertext product covering the
             accounting/auditing subject area.  The DaTa hypertext
             currently (March, 1991) occupies one hundred megabytes of
             disk space, containing approximately 60,000 screens and
             more than 150,000 hypertext links.  The system is
             maintained in about 200 highly interconnected hierarchical
             networks.  The complex structure is maintained and updated
             using the Houdini matrix outliner.

                   The James Martin Report on text management praises
             the MaxThink structural approach in his publication on text
             management (Dewire and Locke 1990) <refs -dewire>. They
             note:

                 It is the ability to categorize and classify ideas in
                 ways that match the needs of users that creates
                 efficient hypertext applications.  Hierarchies are a
                 universally understood method of communicating
                 information.  A hierarchy is a subset of a network,
                 graph, lattice, or outline.  However, in searching for
                 the best hierarchical format for information, a network
                 is often the best place to start.  Networks allow users
                 to rapidly classify information by multiple dimensions
                 without forcing them to immediately choose which
                 dimension belongs at each level in the ultimate
                 hierarchy. ([p.] 4/MAXTHINK)


                              The Library View of Hypertext

                   Except for a few general articles, the library
             literature has essentially ignored hypertext system
             activity and promise.  There has not been library
             appreciation or application of the technology for
             substantial information access system purposes.  The
             university libraries have been involved in the major Brown
             University and USC hypertext projects mentioned above, but
             they are portrayed primarily as cooperative team members
             within the respective academic communities.  They do not
             appear to have been real innovators or leaders of these
             projects.  Literature on these two projects addresses
             primarily the educational and multimedia applications, not
             the nitty-gritty concerns of knowledge organization and
             information access development.

                   Bevilacqua (1989) <refs -bevil>, Debuse (1988)
             <refs -debuse>, and Franklin (1988) <refs -franklin> have
             contributed short introductory articles in the library
             press. They give general overviews of the hypertext
             associative linking approach, and suggest possible impact
             on libraries and information retrieval. Gaines and Vickers
             (1988) <refs -gaines> have produced a more substantial
             piece, delving into the theoretical constructs and
             possibilities of hypertext and hypermedia systems. Urr
             (1991) <refs 23 8> discusses the lack of organization and
             structure evidenced or supported by most reported hypertext
             implementations. He echoes Gaines and Vickers in
             criticizing false or pseudo-hypertext system claims.

                   The major notice of hypertext potential by the
             library and information community has taken place at
             Linkping university in Sweden, by investigators associated
             with the LIBLAB project.  Hjerppe and his associates have
             undertaken this substantial research effort. The LIBLAB
             investigation is studying the effects and potentials of the
             evolving electronic information environment upon the
             library of the future.  A primary focus of the research
             program involves development of the HYPERCATalog system.
             This is envisioned as a hypertext format online public
             access catalog (OPAC), as well as a personalized
             information system for library users.

                   Hjerppe has published numerous outlines of LIBLAB
             project goals and plans (Hjerppe, 1990b <refs 13 13>, 1989
             <refs 13 4>, 1986 <refs 12 20>; Hjerppe, Bivens-Noerr, and
             Noerr 1982) <refs 13 24>. He has also presented detailed
             considerations of knowledge organization and the evolution
             of the library roles in the emerging electronic society
             (1990a <refs 13 8>, 1990c <refs 13 19>)

                   Bjrklund describes the possibilities of the
             HYPERCATalog as a researcher tool (1990a) <refs 2 21>. She
             has also reported on the experimental hypertext conversion
             of a section of the Swedish "SAB" hierarchical
             classification (1990b) <refs 3 4>. As in other LIBLAB
             electronic classification and cataloging code efforts, they
             found that hypertext conversion of the hierarchical
             classification highlighted inconsistencies in the existing
             classification.

                   Vainio-Larsson, another LIBLAB researcher, has
             produced two articles (1989a <refs 23 18>, 1989b
             <refs 24 1>) delving into hypertext system/user
             interactions and the potential HYPERCATalog application. He
             analyzes the concept of the user mental model of the
             system, and the role of metaphor in the system interface.

                            Literature Review Conclusion

                   This review of the general information access
             literature and specific hypertext literature provides a
             base for the present study.  In this review, the writer has
             shown the background and need for the study.  This study is
             an analysis of traditional information access approaches
             and their possible application to a new electronic
             information delivery medium.
