We developed a method to automatically assess texts for features that help readers produce gist inferences. Following fuzzy-trace theory, we used a procedure in which participants recalled events under gist or verbatim instructions. Applying Coh-Metrix, we analyzed written responses in order to create gist inference scores (GISs), or seven variables converted to Z scores and averaged, which assess the potential for readers to form gist inferences from observable text characteristics. Coh-Metrix measures reflect referential cohesion and deep cohesion, which increase GIS because they facilitate coherent mental representations. Conversely, word concreteness, hypernymy for nouns and verbs (specificity), and imageability decrease GIS, because they promote verbatim representations. Also, the difference between abstract verb overlap among sentences (using latent semantic analysis) and more concrete verb overlap (using WordNet) should enhance coherent gist inferences, rather than verbatim memory for specific verbs. In the first study, gist condition responses scored nearly two standard deviations higher on GIS than did the verbatim condition responses. Predictions based on GIS were confirmed in two text analysis studies of 50 scientific journal article texts and 50 news articles and editorials. Texts from the Discussion sections of psychology journal articles scored significantly higher on GIS than did texts from the Method sections of the same journal articles. News reports also scored significantly lower than editorials on the same topics from the same news outlets. GIS proved better at discriminating among texts than did alternative formulae. In a behavioral experiment with closely matched text pairs, people randomly assigned to high-GIS versions scored significantly higher on knowledge and comprehension.
Keywords: Discourse technology; Patient education; Readability; Understanding.