Hypotheses

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Productivity can be limited by the users' abilities, the performance of the computing platform, the application being used, and the tasks being completed. By increasing the demands placed upon the user, high-demand tasks will lead to lower productivity. Even the least powerful platform is capable of providing adequate support for data entry activities. Therefore, more powerful computing platforms will allow for increased productivity only if these platforms allow non-data entry activities to become more efficient. The majority of non-data entry activities will be associated with navigation, which suggests that navigation must become more efficient for more powerful platforms to lead to increased productivity. Finally, more powerful platforms will allow for faster responses, smoother scrolling, and other potentially subtle changes in the users' experiences. The following hypotheses are based upon these observations, the demands our tasks place upon the users and computers, and the applications required to complete these tasks. Additional details regarding the tasks are provided below in the Methods section.

H1: High-demand tasks will result in significantly longer task completion times than low-demand tasks. This will be true for all three applications.

H2: High-demand tasks will result in significantly higher error rates than low-demand tasks. This will be true for all three applications.

H3: The majority of the additional time required to complete high-demand tasks, as compared to low-demand tasks, will be due to differences in cognitive demands as opposed to physical demands.

H4: More powerful computing platforms will result in significantly shorter task completion times only if they allow for a significant reduction in the time required for navigation activities.

H5: More powerful computing platforms will result in significantly higher (i.e., more positive) user perception ratings.

We assess productivity in terms of the time required to complete the tasks and the errors that occur. H1, H2, and H3 were defined to highlight the relationship between productivity and the demands tasks place on users. H1 is motivated, in large part, by the additional data entry required by high-demand tasks. In contrast, H2 is motivated by the additional cognitive demands users experience when completing the high-demand tasks. H3 was included to emphasize the importance of cognitive demands as compared to physical demands. H4 and H5 were included to provide insights into the importance of the computing platform being used to complete the tasks.

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