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

Area of Science:

• Human-Computer Interaction
• Cognitive Psychology
• Gerontology

Background:

• The Card, Moran, and Newell (1983) Model Human Processor (MHP) is a foundational cognitive model.
• Understanding age-related differences in information processing is crucial for designing inclusive technologies.
• Existing MHP models may not fully capture the nuances of older adult cognitive performance.

Purpose of the Study:

• To estimate weighted mean values for nine information processing parameters specific to older adults.
• To validate these parameters by modeling mobile phone tasks for both younger and older adults.
• To assess the utility of these parameters in identifying design flaws impacting older users.

Main Methods:

• Utilized the Card, Moran, and Newell (1983) Model Human Processor (MHP) framework.
• Estimated nine key information processing parameters for an older adult population.
• Modeled two mobile phone tasks, comparing MHP predictions with empirical data from younger (M-age=20) and older (M-age=69) participants.

Main Results:

• Older adult MHP models demonstrated a high degree of accuracy in predicting keystroke-level performance (R=0.99).
• Model fits for older adults were comparable to those previously established for younger adults.
• Critical path analyses identified specific design elements (cognitive workload, hardware/software, user characteristics) contributing to performance decrements.

Conclusions:

• The estimated older adult information processing parameters are valid for predictive modeling.
• These parameters provide valuable insights for designers seeking to understand age-related performance on existing interfaces.
• The findings support the development of technologies that are more sensitive and responsive to the needs of older users.