How to study and design for
collaborative browsing in the Digital Library

Discussion Document for:

How We Do User-Centered Design and Evaluation of Digital Libraries:
A Methodological Forum

37th Allerton Institute
Graduate School of Library and Information Science
University of Illinois at Urbana-Champaign
Allerton Park & Conference Center
Monticello, Illinois

October 29-31, 1995

Michael Twidale

Computing Department
Lancaster University

'Libraries are meeting places where collaborations can and do happen.'
Levy & Marshall, pg 165, Proceedings of Digital Libraries '94 (College Station, Texas)

Libraries aren't just for Loners

If we look at existing physical libraries there is a surprising amount of social interaction that occurs. Some kinds of interaction have been studied in the library science literature, other have not. This discussion document raises some of the issues that we may choose to explore and elaborate in the session. I hope that other participants will want to raise related issues in considering the social aspects of Digital Libraries.

If you want to find out more about our work at Lancaster on collaborative browsing, check out our URL:

There are papers, comments, screendumps of our ARIADNE system and pointers to other Digital Libraries projects.

What are the kinds of social interaction in libraries?

  1. Individual users interacting with individual librarians. This includes the well studied reference interview.

  2. Library staff collaborating with each other, co-working on a common task, sharing hints tips and expertise in tacking a tricky search request of a client, teaching and learning from each other, particularly as new databases and information systems flood in, and the interfaces to existing systems are continually updated

  3. Users interacting with each other. Libraries are public spaces. People arrange to meet there, bump into acquaintances and colleagues and can learn from each other by observing how others use the library's resources, or by asking them for help. Our informal studies at Lancaster University's library has revealed a substantial amount of interaction occurring around the OPAC and CD-ROM terminals. Groups of students bunch round one terminal discussing what they are doing or lean over to observe what their neighbour is doing and ask for help.

  4. Any others??

What is worth noting is that all this cooperation and peer teaching often occurs DESPITE the existing computer systems rather than because of them. The systems are mostly designed to support the individual user: the lonely scholar who seems to have been the envisaged user. Indeed most of the work in database design in Computing Research has focused on how to make the user of a database feel that they are the sole user: to make other users completely invisible. In effect this approach when extended to a digital library will lead us to construct an entire virtual library for each user which they can wander around entirely alone. I see this as a dangerous trend in digital libraries; besides the fact that presented in such stark terms it sounds rather cold and soulless, from an information seeking perspective it is inefficient. Eliminating the other users of the library from your experience reduces the resources you have to help you in your searching.

The danger is that the trend to increasing use of remote access to libraries will divorce users from each other and mean that they are unable to ask people for help, serendipitously to bump into people or just watch what others are up to. That is, the move to digital libraries may lead to a loss of some very advantageous features in physical libraries, unless we take active measures to re-introduce them.

The other, more positive, side of this approach is that the move to digital libraries offers the opportunity for far greater and more diverse kinds of collaboration than are possible in physical libraries. You can collaborate with people who live tens or thousands of miles away. You can collaborate even if you are not using the library at exactly the same time.

The challenge is to develop systems that support the kinds of collaboration that people will want to use that will help them in their use of a library whose size will be growing at an ever faster rate, and whose information systems are likely to be revised far more frequently than is the case for most physical libraries.

What are the kinds of things that people will want to collaborate about?


Given the huge size and number of databases we cannot expect even expert information scientists to be fully conversant with them all. A search request may need to be split between several people with slightly differing expertise and the results combined. Often sharing their experiences will lead to other ideas for further searching strategies.


The continual growth and redevelopment of the systems will lead to a continual need for learning and updating skills. This can be done most effectively as part of the working process when working with others and sharing expertise.

What do we mean by collaborative browsing?

Provisional Definition:

Collaborative browsing includes all aspects of the information retrieval process
that involve interaction between people (and agents?)

We use searching as a generic term for all kinds of information retrieval activity. However, we are particularly interested in a form of searching (for which we use the term browsing) that involves a search for information whose nature is difficult to precisely specify in advance. That is, the search goals evolve during, and as a consequence of, the search process.

Here are some examples of collaborative browsing (we expect our research to reveal others):

Collaborative learning

Collaborative learning occurs when colleagues share hints and tips on how to use information systems. This most easily happens when working is co-located: walking into a colleague's office and asking for help or noticing that they are doing something clever and asking about it.

A substantial amount of collaborative learning occurs in libraries. Some may be formally organised by library staff, but there is also informal, spontaneous collaborative learning: users sit round terminals in small groups explaining techniques to each other, lean over to adjacent terminals and ask friends or neighbours for help. Library staff help end-users with their problems in-situ; synchronously and co-located. To observers from the Educational Research world this natural phenomenon is greatly to be desired and much effort is often made to convert conventional teaching approaches into such authentic, situated, collaborative learning activities. Therefore we should consider how to support this kind of learning which has evolved spontaneously as a user-centred solution to their problems.

In addition to the educational advantages of formal and informal collaborative learning, there is the potential for significant cost savings compared to traditional forms of teaching. This is an important consideration with a growth both in the numbers of people needing to learn search skills (and this includes library staff as well as end users) and in the amount of things that they have to learn.

Informal contacts with colleagues: Serendipitous Altruism

Colleagues in a community may be willing to help each other's information searching even if they are not directly involved in the project. In the field of software engineering this has been noted for some time as the 'coffee machine phenomenon': software developers stand round the coffee machine discussing their work and colleagues offer suggestions of how to solve the problem. With respect to information retrieval activity we believe the equivalent effect can occur, provided structures are in place to support it. We refer to the idea as serendipitous altruism.

Serendipity has been long acknowledged within information retrieval as a phenomenon that skilled searchers know how to allow for and to exploit. However it need not just be personal. If your colleagues know what you are working on and happen by accident, in the process of undertaking their own searches, to come across something that may be of interest, they may altruistically pass the information on to you. The expectation is that, in similar circumstances, you will in future return the favour. It is important to note that the cost (in effort) to the benefactor must be minimal. That is why offering advice in a social context over a coffee is effective and why electronic mail and related systems facilitate the forwarding of potentially useful information to those whom the benefactor believes might be interested.

Browsing for people

Most OPACs and databases do not provide mechanisms to support social activities. This can be attributed to an implicit general belief on the part of system designers: you can only browse for inanimate objects. The information present in databases is not limited to the items themselves; potentially it also includes the records of all previous searches. This information can be used to locate the most valuable resource of all - people with similar interests. For example, upon seeing a colleague in an unexpected part of the library, you might choose to ask what she has found there. Similarly, upon seeing someone in 'your' area, you may decide to introduce yourself as someone also interested in that field. Browsing for people, their electronic representations or representations of their activities, is a neglected and important area.

Search re-use

Many searches duplicate previous searches - yet the information is lost and new searchers have to re-invent the wheel. We want to support the re-use of searches and take advantage of other searcher's efforts to retrieve additional records. One concept that can be used to promote search re-use is that of the similar searcher; another user who has searched for some of the same information that you are currently looking at. Items that similar searchers have retrieved but you haven't seen are likely to be highly relevant. Support for accessing these items can be provided to improve the efficiency and effectiveness of searches and is highly suited to digital libraries. This is a form of anonymous asynchronous (probably remote) collaboration; in the same way as the users of a bibliography are unknown to its compiler.

These points fall under the theme of community (or organisational) memory : the preservation and dissemination of the knowledge (and activities) of members of the community. At present much information is lost as no steps are taken to preserve it: many activities simply repeat previous actions and fail to utilise anything learnt about the activity.

Sharing information: product and process

Collaboration implies a need to share information: both the end product (the hits; what you found) and the process (the search strategy/tactics; how you found it). It helps to share both with the information intermediaries (and other community members), for whom inspection of the search process can reveal not only gaps in the user's browsing techniques but also an indication of their degree of searching sophistication. In addition, an externalised representation of the search process reduces cognitive load and facilitates reflection - a vital component of learning.

We believe that the external representations of the search should have features that minimise communication failures, but also support the detection and remediation of these errors by the participants. To achieve this computer support should enable searches to be visualised, communicated, edited and annotated. Our Ariadne system addresses these issues.

Although the digital library threatens existing collaborative activities it also opens up new opportunities that are presently prevented by the physical constraints of traditional libraries. For example, library staff can help searchers in any part of the world rather than only those who can make their way to the enquiries desk.

Physical libraries limit serendipitous meetings in several ways:

A digital library could provide mechanisms to get round these limitations.

One might ask for things such as:

Lest this all sound rather utopian, let us remember that:

They must be acceptable in terms not just of being easy to learn and to use but in conforming to the unwritten (and changing) norms of social interaction. And of course new technologies for interaction change those norms. Hence our current confusion over what email is: should it obey the social rules of a telephone conversation or a letter, or have its own separate rules?

Librarians have a long tradition of concern for the privacy of their users. Social interaction can impinge on this unless great care is taken. Furthermore what is acceptable in a physical library (such as watching what others are doing) may not be acceptable in its virtual equivalent in a digital library.

ARIADNE Project | CSEG Group | AAI/AI-ED Group | Computing Department | Lancaster University