Classification of CIR systems

The most common way to classify collaborative activities is based on two factors: location and time (Hansen and Järvelin, 2005). Table 2.2 shows the four classes of collaboration resulting from these two factors. Collaboration within a team may occur with the team members in the same place (co-located collaboration) or with team members distributed between offices or work areas (remote collaboration). In co-located collaborative environments, team members can converse, share documents and demonstrate ideas. In remote collaboration team members frequently turn to email, IM or telephone conversations to facilitate collaboration. Collaboration can also be classified as synchronous or asynchronous. Synchronous collaboration refers to a team working simultaneously on a collaborative task such as information retrieval. Asynchronous collaboration can occur when members keep different work hours or live in different time zones. Asynchronous co-located collaboration faces similar challenges to remote collaboration since the use of a shared work space is meaningless if team members are not there at the same time. Remote collaboration often has an asynchronous nature since members may opt to collaborate via email or other asynchronous means.

Table 2.2: Classification of collaboration by location and time

Physical Location Team members in same location Team members in different locations T ime Team members working simultaneously Synchronous, co- located collaboration Synchronous, remote collaboration Team members working at different times Asynchronous, co- located collaboration Asynchronous, remote collaboration

Collaboration can also be classified as system-mediated or user-mediated (Golovchinsky, Pickens and Back, 2008). System-mediated (or algorithmic) collaboration involves computer systems automatically distributing tasks or results while user-mediated

collaboration has one or more users distributing the workload between the group members. Co-located CIR systems generally use user-mediation as the workload is more easily divided when users are in the same location.

Collaboration can also be active (explicit) or passive (implicit) (Golovchinsky, Pickens, et al., 2008). Active collaboration occurs when users actively form a collaborative group and implies a structured collaboration where users may have specific roles. This is the most common form of collaboration in an organisational context. In passive collaboration users may not know the users they are collaborating with or even that they are collaborating at all. This occurs particularly with system-mediated collaboration across networks. Search results may be automatically sorted by relevance determined from the actions or ratings of other users.

Synchronous, co-located collaboration may be supported by multi-user computer systems. Multi-user computer systems imply active collaboration as the users will be part of the same team and highly aware of the other users’ actions. There is a lack of specialised systems for this kind of collaboration and users frequently must make use of computer systems designed for one user (Stewart et al., 1999). This research will thus focus on synchronous, co-located, active, user-mediated collaboration.

2.6.5 Functional requirements of CIR

The tasks required for CIR were identified in Section 2.4. Twelve general functional requirements of CIR have been identified, which are summarised in Table 2.3.

Table 2.3: General functional requirements of a CIR system

1. Provide shared access to an information space

2. Search by collaboratively querying and filtering the information space

3. Present or visualise the search results or shared information

4. Collaboratively navigate through and retrieve search results

6. Manipulate the search results or shared information

7. Update or add value to shared information

8. Update users on other users’ actions

9. Enable communication between group members

10. Enable division of workload between group members

11. Store logs of user actions, such as communication and searches

12. Enable users to refind and reuse information

Users of a CIR system require access to an information space, which may be a database, a set of documents, or the World Wide Web. Users search the information space using collaborative querying and/or collaborative filtering. The results need to be presented in a way that is meaningful with regard to the data. Twidale and Nichols (1998) made use of virtual cards to visualise past search results. The results can then be navigated through to retrieve a document. The representations of the results may be manipulated to order or categorise the information. The information may also be updated or have value added to it in the form of annotations, ratings or automatic statistics such as number of times opened. To be an effective collaborative system a number of functions need to be supported that facilitate awareness and communication (Morris and Horvitz, 2007). Awareness of other group members’ results is essential in collaboration and in some cases sharing of information is the main goal of collaboration. Awareness of other members’ activities during the information retrieval process is important to reduce duplication of effort and to promote learning of information retrieval techniques (such as effective querying) from other members. The system should keep users updated about each other’s actions, enable communication between them, such as with integrated IM.

Persistence of information is a related concept to awareness. Persistent information is information that is stored for later access by a group member, which facilitates greater awareness amongst the team of each other’s and their own activities. Users of systems without strong persistence of information may find themselves entering a search term multiple times in order to re-find information (Teevan, Adar, Jones and Potts, 2006) to ensure the persistence of information found and generated through the use of the tool, actions should be logged and queries and filters stored to enable users to refind and reuse information that has been found previously.

Division of labour can be supported by dividing tasks, keywords or concepts between team members (Amershi and Morris, 2008). Manual division of labour is a communication- intensive process and requires team members to converse or use email, IM or the telephone. One method to support division of labour is using ratings and recommendations of documents to bring important information to the attention of other group members (Turnbull, 2007).