[show abstract][hide abstract] ABSTRACT: When gathering feedback about an envisioned system, prototypes communicate design ideas to user groups. However, it is unclear how user responses are affected by prototype format. We conducted a 2x2 quasi-experiment (video /storyboard format x older and younger user groups) to test for an interaction between prototype format and user group. We found a significant interaction between prototype format and responses across user groups. Our results indicate that differences in user responses can be misinterpreted as the result of user group characteristics. We advise using multiple prototype formats to counteract a 'media effect'. Alternatively, we advise using storyboards for a smaller 'media effect'. Author Keywords Prototyping, video, storyboard, scenario based design, eldercare.
Proceedings of the 27th International Conference on Human Factors in Computing Systems, CHI 2009, Boston, MA, USA, April 4-9, 2009; 01/2009
[show abstract][hide abstract] ABSTRACT: This paper explores the use of hyper-heuristics for variable and value ordering in binary Constraint Satisfaction Problems (CSP). Specifically, we describe the use of a symbolic cognitive architecture, augmented with constraint based reasoning as the hyper-heuristic machine learning framework. The underlying design motivation of our approach is to "do more with less." Specifically, the approach seeks to minimize the number of low level heuristics encoded yet dramatically expand the expressiveness of the hyper-heuristic by encoding the constituent measures of each heuristic, thereby providing more opportunities to achieve improved solutions. Further, the use of a symbolic cognitive architecture allows us to encode hierarchical preferences which extend the effectiveness of the hyper-heuristic across problem types. Empirical experiments are conducted to generate and test hyper-heuristics for two benchmark CSP problem types: Map Coloring; and, Job Shop Scheduling. Results suggest that the hyper-heuristic approach provides a dramatically higher level of representational granularity allowing superior intra-problem and inter-problem solutions to be secured over traditional combinations of variable and value ordering heuristics.
Genetic and Evolutionary Computation Conference, GECCO 2009, Proceedings, Montreal, Québec, Canada, July 8-12, 2009, Companion Material; 01/2009