A model of the perceptual and conceptual processes in graph comprehension.

The article proposes that graph comprehension emerges from an integrated sequence of several types of processes: pattern-recognition processes that encode graphic patterns, interpretive processes that operate on those patterns to retrieve or construct qualitative and quantitative meanings, and integrative processes that relate these meanings to the referents inferred from labels and titles. The model is supported by 2 studies that examine the pattern and durations of eye fixations as a person interprets line graphs or answers questions about line graphs that vary in type and complexity. One implication is that graph comprehension might be more accurate and more complete if the graph's format were changed or the audience were educated to lessen the burden of the inferential, interpretive, and integrative processes. In this article, we propose a model of the comprehension of line graphs that emphasizes the close interaction between conceptual processes, such as interpreting labels and scales, and perceptual processes, such as encoding and interpreting the slopes and patterns of the lines themselves. The model accounts for the pattern and duration of the eye fixations of college students who are interpreting line graphs with three dimensions. Moreover, it provides a theoretical framework for analyzing the processing of more complex graphs, more complex tasks, and other types of audiences (novices vs. experts). This focus on the conceptual aspects of graph interpretation contrasts with the implicit assumption of some researchers and graphic designers that graph comprehension is