Krzysztof Z. Gajos
About the author:
No description available of Krzysztof Z. Gajos...
Publications by Krzysztof Z. Gajos (bibliography)
» 2009 «
Spaulding, Aaron, Gajos, Krzysztof Z., Jameson, Anthony, Kristensson, Per Ola, Bunt, Andrea and Haines, Will (2009): Usable intelligent interactive systems: CHI 2009 special interest group meeting. In: Proceedings of ACM CHI 2009 Conference on Human Factors in Computing Systems 2009. pp. 2743-2746. Available online
The AI and HCI communities have often been characterized as having opposing views of how humans and computers should interact" observes Winograd in Shifting Viewpoints. It is time to narrow this gap. What was once considered the forefront of artificial intelligence (AI) research can now be found in commercial products. While some have failed, others, such as face detection in digital cameras or product recommendation systems, have become so mainstream they are no longer thought of as artificial intelligence. This special interest group provides a forum to examine the apparent gap between HCI and AI communities, to explore how intelligent technologies can enable novel interaction with computation, and to investigate the challenges associated with understanding human abilities, limitations, and preferences in order to drive the design of intelligent interactive systems.
Copyrights may apply
» 2008 «
Gajos, Krzysztof Z., Wobbrock, Jacob O. and Weld, Daniel S. (2008): Improving the performance of motor-impaired users with automatically-generated, ability-based interfaces. In: Proceedings of ACM CHI 2008 Conference on Human Factors in Computing Systems April 5-10, 2008. pp. 1257-1266. Available online
We evaluate two systems for automatically generating personalized interfaces adapted to the individual motor capabilities of users with motor impairments. The first system, SUPPLE, adapts to users' capabilities indirectly by first using the ARNAULD preference elicitation engine to model a user's preferences regarding how he or she likes the interfaces to be created. The second system, SUPPLE++, models a user's motor abilities directly from a set of one-time motor performance tests. In a study comparing these approaches to baseline interfaces, participants with motor impairments were 26.4% faster using ability-based user interfaces generated by SUPPLE++. They also made 73% fewer errors, strongly preferred those interfaces to the manufacturers' defaults, and found them more efficient, easier to use, and much less physically tiring. These findings indicate that rather than requiring some users with motor impairments to adapt themselves to software using separate assistive technologies, software can now adapt itself to the capabilities of its users.
Copyrights may apply
Gajos, Krzysztof Z., Everitt, Katherine, Tan, Desney S., Czerwinski, Mary and Weld, Daniel S. (2008): Predictability and accuracy in adaptive user interfaces. In: Proceedings of ACM CHI 2008 Conference on Human Factors in Computing Systems April 5-10, 2008. pp. 1271-1274. Available online
While proponents of adaptive user interfaces tout potential performance gains, critics argue that adaptation's unpredictability may disorient users, causing more harm than good. We present a study that examines the relative effects of predictability and accuracy on the usability of adaptive UIs. Our results show that increasing predictability and accuracy led to strongly improved satisfaction. Increasing accuracy also resulted in improved performance and higher utilization of the adaptive interface. Contrary to our expectations, improvement in accuracy had a stronger effect on performance, utilization and some satisfaction ratings than the improvement in predictability.
Copyrights may apply
Wobbrock, Jacob O. and Gajos, Krzysztof Z. (2008): Goal Crossing with Mice and Trackballs for People with Motor Impairments: Performance, Submovements, and Design Directions. In ACM Transactions on Accessible Computing, 1 (1) p. 4
Prior research shows that people with motor impairments face considerable challenges when using conventional mice and trackballs. One challenge is positioning the mouse cursor within confined target areas; another is executing a precise click without slipping. These problems can make mouse pointing in graphical user interfaces very difficult for some people. This article explores goal crossing as an alternative strategy for more accessible target acquisition. In goal crossing, targets are boundaries that are simply crossed by the mouse cursor. Thus, goal crossing avoids the two aforementioned problems. To date, however, researchers have not examined the feasibility of goal crossing for people with motor difficulties. We therefore present a study comparing area pointing and goal crossing. Our performance results indicate that although Fitts' throughput for able-bodied users is higher for area pointing than for goal crossing (4.72 vs. 3.61 bits/s), the opposite is true for users with motor impairments (2.34 vs. 2.88 bits/s). However, error rates are higher for goal crossing than for area pointing under a strict definition of crossing errors (6.23% vs. 1.94%). We also present path analyses and an examination of submovement velocity, acceleration, and jerk (the change in acceleration over time). These results show marked differences between crossing and pointing and almost categorically favor crossing. An important finding is that crossing reduces jerk for both participant groups, indicating more fluid, stable motion. To help realize the potential of goal crossing for computer access, we offer design concepts for crossing widgets that address the occlusion problem, which occurs when one crossing goal obscures another in persistent mouse-cursor interfaces. This work provides the motivation and initial steps for further exploration of goal crossing on the desktop, and may help researchers and designers to radically reshape user interfaces to provide accessible goal crossing, thereby lowering barriers to access.
Copyrights may apply
» 2007 «
Wobbrock, Jacob O. and Gajos, Krzysztof Z. (2007): A comparison of area pointing and goal crossing for people with and without motor impairments. In: Ninth Annual ACM Conference on Assistive Technologies 2007. pp. 3-10. Available online
Prior work has highlighted the challenges faced by people with motor impairments when trying to acquire on-screen targets using a mouse or trackball. Two reasons for this are the difficulty of positioning the mouse cursor within a confined area, and the challenge of accurately executing a click. We hypothesize that both of these difficulties with area pointing may be alleviated in a different target acquisition paradigm called "goal crossing." In goal crossing, users do not acquire a confined area, but instead pass over a target line. Although goal crossing has been studied for able-bodied users, its suitability for people with motor impairments is unknown. We present a study of 16 people, 8 of whom had motor impairments, using mice and trackballs to do area pointing and goal crossing. Our results indicate that Fitts' law models both techniques for both user groups. Furthermore, although throughput for able-bodied users was higher for area pointing than for goal crossing (4.72 vs. 3.61 bits/s), the opposite was true for users with motor impairments (2.34 vs. 2.88 bits/s), suggesting that goal crossing may be viable for them. However, error rates were higher for goal crossing than for area pointing under a strict definition of crossing errors (6.23% vs. 1.94%). Subjective results indicate a preference for goal crossing among motor-impaired users. This work provides the empirical foundation from which to pursue the design of crossing-based interfaces as accessible alternatives to pointing-based interfaces.
Copyrights may apply
Gajos, Krzysztof Z., Wobbrock, Jacob O. and Weld, Daniel S. (2007): Automatically generating user interfaces adapted to users' motor and vision capabilities. In: Proceedings of the ACM Symposium on User Interface Software and Technology October 7-10, 2007, Newport, Rhode Island, USA. pp. 231-240. Available online
Most of today's GUIs are designed for the typical, able-bodied user; atypical users are, for the most part, left to adapt as best they can, perhaps using specialized assistive technologies as an aid. In this paper, we present an alternative approach: SUPPLE++ automatically generates interfaces which are tailored to an individual's motor capabilities and can be easily adjusted to accommodate varying vision capabilities. SUPPLE++ models users. motor capabilities based on a onetime motor performance test and uses this model in an optimization process, generating a personalized interface. A preliminary study indicates that while there is still room for improvement, SUPPLE++ allowed one user to complete tasks that she could not perform using a standard interface, while for the remaining users it resulted in an average time savings
Copyrights may apply
» 2006 «
Gajos, Krzysztof Z., Long, Jing Jing and Weld, Daniel S. (2006): Automatically generating custom user interfaces for users with physical disabilities. In: Eighth Annual ACM Conference on Assistive Technologies 2006. pp. 243-244. Available online
Gajos, Krzysztof Z., Czerwinski, Mary, Tan, Desney S. and Weld, Daniel S. (2006): Exploring the design space for adaptive graphical user interfaces. In: Celentano, Augusto (ed.) AVI 2006 - Proceedings of the working conference on Advanced visual interfaces May 23-26, 2006, Venezia, Italy. pp. 201-208. Available online
SHOW THIS LIST ON YOUR HOMEPAGE
What do YOU think?
Give us your opinion! Do you have any comments/additions
that you would like other visitors to see?
You say:
Mar 22nd, 2010
Changes to this page (author)
16 Feb 2010: Enabled abstracts to be shown on Krzysztof Z. Gajos's author page.17 Jun 2009: Author was edited 03 Jun 2009: Author was edited
09 May 2009: Author was edited
12 May 2008: Author was edited
12 May 2008: Author was edited
12 May 2008: Author was edited
12 May 2008: Author was edited
22 Jun 2007: Author was added to the bibliography