Effects of Graphs on Text Comprehension

Sources of information, from textbooks to multimedia encyclopedias combine text and graphics. This paper applies the construction-integration model of text comprehension to the processing of text and quantitative graphs. The model suggests that, when reading a graph that has information that is redundant with the text, a reader may directly connect the propositional information from the graph and the text due to overlap. When reading a graph that has information that elaborates on the text, a reader makes inferences to connect the propositional information from the graph and the text. Hypotheses from this model are that (1) use of an elaborative graph should produce better comprehension if the graph and text are concurrent, whereas (2) use of a redundant graph should produce better comprehension if the graph and text are separated. Three experiments tested these hypotheses by giving readers text with three types of graphs – text only, redundant graphs, and elaborative graphs — with the graphs either concurrent with (Experiment 1), before (Experiment 2A), or after (Experiment 2B) the text, then giving readers text-based or inference-based questions. In all three orders of the graph and text, performance on the inference-based questions was better in the elaborative graph condition than in the redundant graph condition. The discussion extends the application of the construction-integration model to reading text with graphs.