LAG 2.0: Refining a Reusable Adaptation Language and Improving on Its Authoring

Reusable adaptation specifications for adaptive behaviour has come to the forefront of adaptive research recently, with EU projects such as GRAPPLE, and PhD research efforts on designing an adaptation language for learning style specification [ 28]. However, this was not the case five years ago, when an adaptation language for adaptive hypermedia (LAG) was first proposed. This paper describes the general lessons learnt during the last five years in designing, implementing and using an adaptation language, as well as the changes that the language has undergone in order to better fulfil its goal of combining a high level of semantics with simplicity, portability as well as being flexible. Besides discussing these changes based on some sample strategies, this paper also presents a novel authoring environment for the programming-savvy adaptation author, that applies feedback accumulated during various evaluation sessions with the previous set of tools, and its first evaluation with programming experts.