Escape from the tyranny of the textbook: Adaptive object inclusion in AHA!

Adaptation in on-line textbooks makes it possible to allow learners to study the textbook in different ways without encountering difficulties. Conditional inclusion of fragments and stretchtext make it possible to provide additional or prerequisite explanations when needed or desired. In this paper we present a new and more flexible way to conditionally include information: adaptive object inclusion. We realize that when applications become more and more dynamic users may start to feel uneasy when the presentation of the same information or concepts changes all the time. We therefore also introduce the idea of stable presentations, a technique to limit the adaptation to information the user has not yet visited. We have implemented both new techniques in the AHA! system.