Design and Evaluation of Ambient Displays

The aim of this thesis is to better support the design and evaluation of ambient displays. The major difficulty is how to evaluate them. For the furtherance of this aim, seven specific questions are raised. The answers to these seven specific questions are based on the four case studies and the relevant literature. In this thesis, first we systematically divide the evaluation of ambient displays into intrusive and non-intrusive evaluations. Intrusive evaluation is where the user is consciously aware of the evaluation experiment. This is not so in non-intrusive evaluation. For each evaluation style, the evaluation dimensions and their related attributes, evaluation criteria and evaluation techniques are accordingly introduced. Specifically, usefulness is the dimension of non-intrusive evaluation, which can be further divided into usability and utility. Usability is also the dimension of intrusive evaluation. Three detailed evaluation criteria for each evaluation style are effectiveness, efficiency and satisfaction. A four step process model for the support of the design and evaluation of ambient displays is also developed. This process model is inspired by the iterative life cycle model and combined consideration of human information processing. Furthermore, guidelines for ambient displays are catalogued. The detailed guidelines come from three different sources: first, to filter and adapt guidelines from other domains. Secondly, to catalogue existing guidelines for ambient displays, and thirdly, to formulate new guidelines from four detailed case studies of this thesis. Finally, four detailed case studies are applied to validate the proposed theories.