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Access

Access is basically finding information in the organization provided by the interface, bringing it onto the screen and making it visible.

In the independent overlapping windows approach, information is accessed one window at a time. However, users typically engage in tasks that require access to multiple pieces of information such as chapters in a large document, related documents, reports, correspondence, etc. In our observations each piece of information is considered as a block and I observed block access frequencies. According to these observations the average block working set sizes are found to be 2.37, 5.92 and 8.43 for 1, 5 and 10 minute periods indicating reasonably high block access patterns. Increasing the capability of operations by providing multi-window operations is likely to help users by allowing them to access multiple pieces of information rapidly.

Granularity of access is also crucial for the efficiency of access. In current systems, information access is only file-based, thus information has a single granularity level for access. However, typically the granularity of information that users access is blocks, such as a few lines of source code. In my observations the average block size is found to be 18.1 lines and the average number of blocks as 23.6 for an hour observation. It is quite tedious to bring up all information needed for the users' task and arrange them on the screen. Allowing access in groups or hierarchies of information would make interfaces more scalable and allow users to setup their task environments rapidly.

In early computer systems, in order to access information users had to recall exact file names, directory structures, etc. These attributes are called nominal attributes of information. Recalling nominal attributes becomes more difficult as the amount of information that users deal with increases. With the introduction of window-based interfaces, users can use spatial attributes such as location of windows to access information. Lansdale observed that current interfaces do not support the variety of activities people use to organize and access information [7]. Lansdale observes that people remember far more about pieces of information than labels (nominal), such as when it was received (temporal), what it looks like (visual), where it was put (spatial), and many other things. Allowing information access through multiple access modalities (i.e. nominal, temporal, visual, and spatial) is likely to improve users' information access performance and satisfaction. According to my observations, users tried to overcome this problem by techniques such as block coloring, partial keyword search, etc.


next up previous
Next: Manipulation Up: Motivation Previous: Organization

Eser Kandogan
Sun Sep 13 18:34:46 EDT 1998

Web Accessibility