[Experimental investigation of the effects of representations and perspectives for the comprehension of line graphs].

The comprehension of graphs is achieved through interaction between bottom-up and top-down processing. This study experimentally investigated the interaction between the graph representations determining bottom-up processing and the reader's perspective relating to top-down processing. Different representations on graphs generated from an identical data set elicited different interpretations of the graphs. We call this the "representation effect" on graph comprehension. In Experiment 1, we confirmed the characteristic of the bottom-up process of graph comprehension by using a set of line graphs which were identical in perceptual characteristics. In Experiments 2A and 2B, the participants were given a perspective for reading the graphs, and then they interpreted the graphs. The results showed that this perspective affected their comprehension of the graphs. Previous studies have shown that top-down processing may not be compatible with bottom-up processing in graph comprehension. However, our result indicated that top-down processing controlled by a perspective for reading the graph was not inconsistent with bottom-up processing, and therefore does not violate bottom-up processing.