Chair: Krzysztof Gajos, Harvard University, United States
Augmenting the Scope of Interactions with Implicit and Explicit Graphical Structures -
PaperContribution & Benefit: Discusses graphical interaction with structures, and with multiple objects through structures. Introduces two novel and consistent interactive tools: ManySpector, an enhanced inspector, and user-provided dependency links.
Abstract » When using interactive graphical tools, users often have to manage a structure, i.e. the arrangement of and relations between the parts or elements of the content. However, interaction with structures may be complex and not well integrated with interaction with the content. Based on contextual inquiries and past work, we have identified a number of requirements for the interaction with graphical structures. We have designed and explored two interactive tools that rely on implicit and explicit structures: ManySpector, an inspector for multiple objects that help visualize and interact with used values; and links that users can draw between object properties to provide a dependency. The interactions with the tools augment the scope of interactions to multiple objects. A study showed that users understood the interactions and could use them to perform complex graphical tasks.
ACM Taming Wild Behavior: The Input Observer for Text Entry and Mouse Pointing Measures from Everyday Computer Use -
PaperContribution & Benefit: Presents a tool that can measure text entry and mouse pointing performance from everyday computer use. Device makers, researchers, and assistive technology specialists may benefit from measures of everyday use.
Abstract » We present the Input Observer, a tool that can run quietly in the background of users� computers and measure their text entry and mouse pointing performance from everyday use. In lab studies, participants are presented with prescribed tasks, enabling easy identification of speeds and errors. In everyday use, no such prescriptions exist. We devised novel algorithms to segment text entry and mouse pointing input streams into �trials.� We are the first to measure errors for unprescribed text entry and mouse pointing. To measure errors, we utilize web search engines, adaptive offline dictionaries, an Automation API, and crowdsourcing. Capturing errors allows us to employ Crossman�s (1957) speed-accuracy normalization when calculating Fitts� law throughputs. To validate the Input Observer, we compared its measures from 12 participants over a week of computer use to the same participants� results from a lab study. Overall, in the lab and field, average text entry speeds were 74.47 WPM and 80.59 WPM, respectively. Average uncorrected error rates were near zero, at 0.12% and 0.28%. For mouse pointing, average movement times were 971 ms and 870 ms. Average pointing error rates were 4.42% and 4.66%. Average throughputs were 3.48 bits/s and 3.45 bits/s. Device makers, researchers, and assistive technology specialists may benefit from measures of everyday use.
ACM Dwell-and-Spring: Undo for Direct Manipulation -
PaperContribution & Benefit: Presents Dwell-and-Spring a technique that uses the metaphor of springs to enable users to undo direct manipulations. Evaluation shows that users quickly adopt it as soon as discovered.
Abstract » In graphical user interfaces, direct manipulation consists in incremental actions that should be reversible. Typical examples include manipulating geometrical shapes in a vector graphics editor, navigating a document using a scrollbar, or moving and resizing windows on the desktop.
As in many such cases, there will not be any mechanism to undo them, requiring users to manually revert to the previous state using a similar sequence of direct manipulation actions. The associated motor and cognitive costs can be high. We argue that proper and consistent mechanisms to support undo in this context are lacking, and present Dwell-and-Spring, an interaction technique that uses the metaphor of springs to enable users to undo direct manipulations. A spring widget pops up whenever the user dwells during a press-drag-release interaction, giving her the opportunity to either cancel the current manipulation or undo the last one. The technique is generic and can easily be implemented on top of existing applications to complement the traditional undo command. Empirical evaluation shows that users quickly adopt it as soon as they discover it.
ACM WindowScape: Lessons Learned from a Task Centric Window Manager -
ToCHIContribution & Benefit: Deployment study of a scaling window manager that supports organization and grouping. Also discusses design process, particularly including alternatives and tradeoffs.
Abstract » People frequently experience difficulty switching between computer-mediated tasks. To help address this, we created WindowScape, a zooming window manager that uses implicit grouping to help users sort windows according to task. WindowScape was intended to provide a more flexible and intuitive grouping model than prior systems. We report on the design process leading up to the system, and alternative designs we explored. We describe a series of formative evaluations that resulted in significant modifications to our initial prototype, as well as a deployment study of the final version, where users lived with WindowScape on a day-to-day basis. Our results from this study reveal how users react to novel aspects of our system, including its particular uses of miniaturization and its approach to grouping. We also discuss the impact of a task-oriented approach to window management on other aspects of user behavior, and the implications of this for future system design.