The role of incidental recall in the design of personal filing systems

The thesis aims to investigate the implications of incidental recall for the design of personal information systems. Incidental recall is defined here as memory, without prior intent to recall, for information that is not meaningfully related to the information handling situation. When an information worker fails to recall how information is filed, is uncertain of its whereabouts, retrieval of that information becomes problematic and can result in the system not being used. One possible approach to solving this problem is to increase technological power, but even though electronic filing systems may offer varied and complex functions to assist information management, these functions lose their value if the systems are not actually used. An alternative approach to solving this problem is tailoring the system to make use of information that human memory can remember with little or no effort, in particular using attributes that human memory can recall incidentally, as labels for files. An experimental paradigm was developed to explore the nature of incidental recall for aspects of office information. The scarcity of investigative work using realistic, information handling, tasks to investigate incidental recall prompted the experimental design using a realistic task for an office worker. A business simulation game was employed involving the subjects sorting information, in the form of documents, based on decisions about their information content. Situated on the documents' were "Icons", logo-like designs, each with unique attributes of colour, location, and shape. Following the sorting task, the subjects participated in an unexpected test for each attribute of the icon. Four experiments were run within this paradigm which involved subjects experiencing varying levels of exposure to different combinations of attributes. The analysis provided substantial evidence for incidental recall of the attributes. Incidental recall of the attributes varied as a function of the task orientation. Evidence suggested a predisposition to integrate colour and shape in memory, while in contrast, location had a tendency to be recalled independently of the other attributes. The findings suggest that incidental recall as a filing aid will be most useful when attributes incidental to the information content are actively used in the course of handling the information.