Abstract
Part I of this article, pp. 259–272, reviewed the relevant literature on advance organizers and suggested that methodological problems in previous advance organizer studies has not resolved the question of whether advance organizers facilitate the acquisition of subordinate information from text. This question is not an unimportant issue to technical communicators, whose readers often need to acquire factual information as well as more general concepts from the expository text they read. In two studies we investigated the influences of reader's background knowledge, advance organizers, relative importance of idea units, and idea units' position within a text structure on the recall of textual information. Subjects read introductory and text materials and subsequently were tested for their recognition of idea units that were structurally high and important, structurally high and unimportant, structurally low and important, or structurally low and unimportant. In the first study, forty-eight college students were randomly assigned to conditions consisting of relevant or irrelevant background, organizer or no organizer, and text or no text. There were significant main effects for having read a relevant text and for importance of idea units, and an interaction between structural level and importance. A significant organizer by text or no text interaction and absence of a significant main effect for the organizer indicated that the organizer influenced text processing rather than priming relevant prior knowledge, which is a previously undocumented requirement of advance organizer research. In the second study, conducted with eighty-eight college students, we substituted a purpose, no purpose condition for the text, no text condition of the first study. We observed a significant main effect for importance and a significant four-way interaction involving structure, importance, background, and organizer. The more relevant knowledge a reader had, the less dependent he or she was on text structure, and an advance organizer compensated for the absence of relevant prior knowledge.