The Need for PI Visualisation

A visual representation of information is more effective than a textual representation (Aires and Gonçalves, 2012). Visualisations are required to display information in a graphical and viewable manner, which should provide a novel means of observing the information. IV is also generally used to provide insight, to support the sense-making process and to amplify cognition using these visualisations (Pousman, Stasko and Mateas, 2007; Heer, 2008).

An advantage of using IV is that multiple attributes of a PI collection (PIC) can be viewed simultaneously to enable users to explore, compare and analyse this PIC in various ways (Indratmo and Vassileva, 2008). IV tools can positively assist with information retrieval and data analysis (Balakrishnan, Fussell and Kiesler, 2008). Gomes et al. (2010) suggest that a meaningful

visualisation technique may be the solution for the difficulty in finding information among the increasing amount of users’ PI. Visualisations may assist a user in finding what s/he is searching for (Al Nasar et al., 2011). Additionally, visualisations provided to a group of users can encourage collaboration (Balakrishnan et al., 2008).

A number of PIM tools exist to organise and visualise PI, but these tools remain largely unused as they do not effectively support access to PI across multiple devices (Rajamanickam, 2009). An interface needs to be designed to support accessing PI across multiple devices, which unifies content and functionality to assist a user in developing his/her own processes, structures and views of his/her personal space of information (PSI) (Jetter et al., 2008). To make effective use of an appropriate PI organisation method, the method should be considered a “view” (Indratmo and Vassileva, 2008). If a PI organisation method is designed, it needs to be visualised to effectively communicate with the user (Rajamanickam, 2009).

Together with the requirement to support multiple PI types, PI visualisation systems should also provide multiple IV techniques and support the tasks related to information retrieval:

3.2.1. Support for Multiple IV Techniques

Dumais et al. (2003) suggest that a list view representation may not be suitable for PIM and state that an improved IV technique may be needed. Sequential grid layouts for media PI items may not be sufficient for information retrieval (Ryu et al., 2010). Ryu et al. (2010) identify that the UI is important for photo management as this is what the user interacts with. If an ontology is used for PI organisation it needs an effective UI and visualisation, otherwise it may become difficult for the end-user to use (Katifori, Vassilakis, et al., 2008; Katifori, Torou, et al., 2008). There has also been research interest in using the visualisation of email archives in order to discover patterns (Viégas et al., 2006).

In addition to the visualisation dependence on the PI organisation, the IV technique(s) used will also depend on the PI types and PICs within a user’s PSI. Each PI type may require a different IV technique (Jetter et al., 2008). Alternatively, a user’s PICs may require different IV techniques. Multiple or nested IV techniques may be needed, as used in the development of the Zoomable Object-oriented Information Landscape (ZOIL) tool for nomadic cross-platform PIM (Jetter et al., 2008), and by Evequoz and Lalanne (2007), who used a network and a TreeMap to visualise an email archive. It will need to be determined which IV techniques will be suitable for which PI type or PIC, or whether these IV techniques may need to be enhanced to support PIM.

The different devices used will also provide unique challenges for visualisation (Jetter et al., 2008). For example, a mobile phone has different constraints from a static device. The IV techniques used will need to be customised for these devices. Additionally, if multiple visualisations of PI are provided, these visualisations need to be co-ordinated (Aires and Gonçalves, 2012). Thus, if a user filters on certain PI, then the other visualisation will be updated to reflect the filtered information.

Indratmo and Vassileva (2008) suggested providing a user with multiple views or perspectives of his/her PSI so that s/he is provided with several visualisation options. This may assist in allowing a user to customise the PIM tool to his/her needs; for example, a user may require visualising his/her PI according to device, PI type, time and so on.

3.2.2. Support for Information Retrieval Tasks

A PI visualisation system needs to support tasks identified for visualisation and tasks identified specifically for PIM. Shneiderman (1996) identified a well-known and commonly used mantra for IV:

“Overview first, zoom and filter, then details-on-demand...”

Several IV tasks were identified that need to be supported when designing an IV tool, namely:  Overview: Provide an overview of the information.

 Zoom: Allow the user to zoom in on information of interest.  Filter: Filter out irrelevant information.

 Details-on-Demand (DoD): Provide details of items of interest when required.  Relate: View the associations between information items.

 History: Provide a history of actions to support exploration.  Extract: Provide a method of extracting the information.

There are various methods for supporting the above-mentioned tasks, for example, an overview can be provided by either providing an interactive overview to assist a user in navigating his/her PI, or by using a fisheye strategy directly over the visualisation. This mantra should be followed when designing visualisation techniques for PIM. A user should be supported in the above tasks when retrieving information using IV. A user should be supported in browsing, searching and filtering to find information items.

In addition to the visualisation tasks mentioned above, tasks specific for PIM need to be supported by the PI visualisation tool as well. The goal of PIM is to enable a user to access his/her PI relevant to his/her location, in the most appropriate form, while supporting the tasks of PIM (Jones and Bruce, 2005). Barreau (1995) originally identified PIM tasks to include the following tasks:  Acquiring;  Organising;  Storing;  Maintaining;  Retrieving;  Producing.

PIM tasks were then later simplified to include the following (Jones and Bruce, 2005):  Keeping (storing);

 Managing (organising and maintaining);

 Finding (searching and browsing for retrieval).

More recently, the key activities for PIM were identified as the following four activities (Indratmo and Vassileva, 2008):

 Acquiring;  Organising;  Retrieving;  Processing.

Lower-level PI tasks for each PI item in the PSI include the following tasks (Jones and Bruce, 2005):  Creating;  Sorting;  Moving;  Naming;  Assigning properties;  Copying;  Distributing;  Deleting;

 Transforming.

The keeping (storing), organising and finding (viewing and retrieving) PIM tasks across multiple devices form the focus of this research. Support for the general PIM tasks as well as the lower- level tasks for each PI item need to be provided by the design of a PI visualisation tool. Additionally, the PI visualisation tool could adapt to allow the user to view newly added PI items, which are different from his/her previous usage of the tool.