e-books for learning and reference: behavioral patterns and design

Levels of abstraction in designing adaptive web-books
Dov Te’eni and Hadar Ronen, Bar-Ilan University
People communicate at different levels of abstraction, depending on the task at hand
and the complexity of the communication. This study examines the implications of
abstraction levels on the design of adaptive digital documents. A 100-page article was
reorganized as a Web-book built around four levels of abstraction, i.e., low levels
consist of specific and concrete descriptions of reality, while high levels consist of
general principles abstracted from specific cases. A field study of unsolicited
readers, as well as a group of solicited readers who were assigned specific problems,
tapped their access patterns. The findings suggest that users vary their allocation of
attention to different levels of abstraction and choose to hide or ignore lower levels
for certain reading tasks. Design of adaptive web-books can consider these findings in
providing a better fit between the presentation of abstraction levels and the reading
tasks. In essence, we propose a new structure for online material that superimposes a
hierarchical model on the common hypertext model.