Some effects of system information in instructions for use

An experiment was carried out to investigate whether it is useful to add system information to procedural information in instructional text. It was assumed that readers of instructions construct both a procedural and a system mental model, and that the latter enables the readers to infer possible missing information in procedural instructions. Moreover, it was assumed that system information would increase the cognitive load during reading and practicing, and that it would affect the appreciation of the instructions as well as the self-efficacy of the reader. The participants in the experiment read instructions and practiced with a fictitious machine before performing a number of tasks and answering a questionnaire. The results indicate that system information increased the cognitive load during reading and decreased self-efficacy, while the instructional text with system information was judged as more difficult. The effect on performance is limited: system information leads to faster performance for correctly completed tasks

Making sense of step-by-step procedures

Procedural instructions that consist of only a sequence of steps will probably be executable, but nevertheless ¿meaningless¿ to users of technical devices. The paper discusses three features that can make procedural instructions more meaningful: adding functional coordinating information, adding information about the use of the technical device in real life, and adding operational information about how the device works. The research literature supports the effectiveness of the first feature, but offers little evidence that real life elements enhance understanding of instructions. As for operational information, the research suggests that users are willing to read it, and that it contributes to better understanding and performance in the long term, but only if it is closely related to the procedure. As a conclusion, we propose a theoretical framework that assumes three levels of mental representation of instructions: syntactical, semantic, and situationa

Which way to turn? Guide orientation in virtual way finding

In this paper we describe an experiment aimed at determining the most effective and natural orientation of a virtual guide that gives route directions in a 3D virtual environment. We hypothesized that, due to the presence of mirrored gestures, having the route provider directly face the route seeker would result in a less effective and less natural route description than having the route provider adapt his orientation to that of the route seeker. To compare the effectiveness of the different orientations, after having received a route description the participants in our experiment had to ‘virtually’ traverse the route using prerecorded route segments. The results showed no difference in effectiveness between the two orientations, but suggested that the orientation where the speaker directly faces the route seeker is more natural

Accessible Website Content Guidelines for Users with Intellectual Disabilities

Background: The W3C Web Accessibility Initiative has issued guidelines for making websites better and easier to access for people with various disabilities (W3C Web Accessibility Initiative guidelines 1999). - \ud Method: The usability of two versions of a website (a non-adapted site and a site that was adapted on the basis of easy-to-read guidelines) was tested with two groups of 20 participants. One group had intellectual disabilities but could read, the other group had no identified intellectual disabilities. In a 2 × 2 experimental design, it was investigated whether the easy-to-read website was indeed better accessible and usable for the participants with intellectual disabilities. - \ud Results: The adaptation of the website worked well for participants with intellectual disabilities. Users without identified intellectual disabilities were as effective with the adapted site as they were with the non-adapted site. - \ud Conclusion: The results form an empirical basis for recommendations about applying guidelines for easy-to-read text on websites for people with intellectual disabilities