The Model Human Processor and the older adult: Parameter estimation and validation within a mobile phone task.

Abstract

The authors estimate weighted mean values for nine information processing parameters for older adults using the Card, Moran, and Newell (1983) Model Human Processor model. The authors validate a subset of these parameters by modeling two mobile phone tasks using two different phones and comparing model predictions to a sample of younger (N = 20; M age = 20) and older (N = 20; M age = 69) adults. Older adult models fit keystroke-level performance at the aggregate grain of analysis extremely well (R = 0.99) and produced equivalent fits to previously validated younger adult models. Critical path analyses highlighted points of poor design as a function of cognitive workload, hardware/software design, and user characteristics. The findings demonstrate that estimated older adult information processing parameters are valid for modeling purposes, can help designers understand age-related performance using existing interfaces, and may support the development of age-sensitive technologies. Keywordsage; modeling; GOMS; human engineering; design; mobile phone A hallmark of good design is represented by the human factors injunction to "know the user" (Nielson, 1994, p. 73) before design specifications are made. It is essential to account for basic human processing requirements in order to optimize performance with respect to time, accuracy, and satisfaction, in order to produce "user-friendly" systems, interfaces, or devices. Research in human factors and human-computer interaction has a legacy of designing products around the needs of the younger user, in part because many designers are young themselves (the largest population density of workers are between the ages of 30-34; National Science Foundation, 2006), and, as a result, older adults often find that they have difficulties interacting with existing technology and report feelings of frustration and confusion when trying to adapt (e.g., Fisk & Rogers, 1997;Rogers, Fisk, Mead, Walker, & Cabrera, 1996;.As it currently stands, older adult competencies and limitations are not usually accounted for in these earliest stages of design and engineering. Some strides have been made to help accommodate older adults to existing systems through modification of interfaces and Correspondence concerning this article should be addressed to: Tiffany S. Jastrzembski, Department of Psychology, Florida State University, 1107 W Call Street, Tallahassee, FL 32306-4301. tiffany.jastrzembski@mesa.afmc.af.mil. Tiffany S. Jastrzembski and Neil Charness, Department of Psychology, Florida State University. HHS Public Access Author Manuscript Author ManuscriptAuthor ManuscriptAuthor Manuscript systems (e.g., changing acceleration of a mouse, enlarging font size, enhancing contrast), or through modification of the individual (e.g., adapting the user to the product with training and practice); yet a disconnect exists between the fields of cognitive aging and human engineering design. Human engineering design refers to testing systems with cognitive models that simulate human performance, so ...

Assessing Selectivity in the Basal Ganglia: The “Gearbox” Hypothesis

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Meta-analysis of age and skill effects on recalling chess positions and selecting the best move

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