  Previous studies on program comprehension were carried out largely in the
context of procedural languages. Our purpose is to develop and evaluate a
cognitive model of object-oriented (OO) program understanding. Our model is
based on the van Dijk and Kintsch's model of text understanding (1983). One key
aspect of this theoretical approach is the distinction between two kinds of
representation the reader might construct from a text: the textbase and the
situation model. On the basis of results of an experiment we have conducted, we
evaluate the cognitive validity of this distinction in OO program
understanding. We examine how the construction of these two representations is
differentially affected by the programmer's expertise and how they evolve
differentially over time.
