Gray, W. D. & Fu, W.-t. (2001)

Gray, W. D., & Fu, W.-t. (2001). Ignoring perfect knowledge in-the-world for imperfect knowledge in-the-head: Implications of rational analysis for interface design. CHI Letters, 3(1), 112-119. Also in ACM CHI'01 Conference on Human Factors in Computing Systems

Ignoring Perfect Knowledge In-the-world for Imperfect Knowledge In-the-head: Implications of Rational Analysis for Interface Design

Memory can be internal or external - knowledge in-the-world or knowledge in-the-head. Making needed information available in an interface may seem the perfect alternative to relying on error prone memory. However, the rational analysis framework (Anderson, 1990) suggests that least-effort tradeoffs may lead to less than perfect performance even when perfect knowledge in-the-world is readily available. The implications of rational analysis for interactive behavior are investigated in two experiments. In experiment 1 we varied the perceptual-motor effort of accessing knowledge in-the-world as well as the cognitive effort of retrieving items from memory. In experiment 2 we replicate one of the experiment 1 conditions to collect eye movement data. The results suggest that milliseconds matter. Least-effort tradeoffs are adopted even when the absolute difference in effort between a perceptual-motor versus a memory strategy is small, and even when adopting a memory strategy results in a higher error rate and lower performance.

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A more complete version of this paper was published in the Cognitive Science journal in 2004. I strongly recommend that you download, read, and cite that version. Click here to go to that page in my downloads.

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