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Switching Between Tools in Complex Applications

Will Schroeder

Journal of Usability Studies, Volume 3, Issue 4, August 2008, pp. 173-188

Article Contents


A more productive understanding of expertise

Although complex software applications must be accessible to novices, for users to remain novices is undesirable. Yet the definition of expert remains elusive. Since user 4 scored as an expert, and rated himself as an expert, I reviewed his test recording to see if there was anything concrete I could say about his expertise. What I saw was an expert as defined by activity theory. No time was spent deciding whether or not to change tools, or which tool to change to. And with each tool his actions were swift and sure, at times almost too fast for me to follow. He was undeniably expert (smooth and rapid) executing the steps of his workflow, and expert (economical and effective) with the tools he chose.

But I could not rate his workflow or his choice of tools so highly. Having watched many programmers try this task, I know that there are better orderings of steps, and better choices of tools than the ones that this user had internalized. Coleridge (1827) defined prose as "words in their best order" and poetry as "the best words in their best order." User 4 produced eloquent prose. The highest level of expertise must be more like poetry.

Activity theory describes the process by which novices learn to produce satisfactory prose. When a workflow is derailed by one of Engestrom's contradictions the same process heals and improves it. But users with operations that employ less effective tools, or switch between tools at less than optimal times, don't run into contradictions. And yet a new and better tool (within the application) that users believing themselves to be functioning at the level of expert do not employ makes them, in some important sense, less than expert.

Adding tools to an application's mix will not likely help users. Even if they (a) become aware of the new features (not easy), and (b) try to weave the new tool into their workflow (lots of extra work). Determining which tool (old or new) works better is neither straightforward nor foolproof.

Extensions of Engestrom's "contradictions" are more likely to succeed if users are made aware of more effective alternative tools at the moment of choice, or notified of ineffective performance at a point when they feel the need to "upgrade" their process. The trick, of course, is making users aware of the information at that pivotal moment.

Interruptions by design

Because of their focus on task work, users sometimes miss points where they ought to be branching. This is why study of interruptions is vital; if users are to make the best choices at the best points in the workflow, can they be prompted to do so?

We want to be able to inject task interruptions in the form of alerts and reminders to influence better tool switching and to improve the timing of tool switching by helping users decide when to switch. The most interesting studies on interruptions deal with interruptions that are distractions from the task (Cutrell et al., 2000; Mark et al., 2005; Speier, Valacich, & Vessey, 1997).

In our testing, interruptions originate either with the participants when the task flow breaks because questions they can't answer come up in the progress of the work ("How do I finish this for loop?"), when the computer throws an error or performs an unexpected action, or when reaching the end of a subtask. Interactions occur at natural activity boundaries and are adequately characterized in our data by the before and after activities and time measurements, frequency, and positioning along the length of subtask and task.

Interruption statistics, within-task completion times, and users' satisfaction with their work indicate the relative magnitude of impact due to interruption position in the task in user input. We can also observe whether interruptions are preceded by a tapering off of productivity as Speier (1997) predicts.

Design for more timely tool changes requires affordances in the user interface that alert users to the pace and effectiveness of their work.

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