Cohesion is a crucial element for understanding texts, particularly for challenging texts that present knowledge demands to the reader (Loxterman, Beck, & McKeown, 1994; McNamara, Kintsch, Songer, & Kintsch, 1996; McNamara & Kintsch, 1996). Hence, measuring cohesion is an important element of discourse processing research (McNamara, Louwerse, McCarthy, & Graesser, 2010). However, freely available natural language processing (NLP) tools that measure linguistic features related to text cohesion are limited.
TAACO is a freely available text analysis tool that is easy to use, works on most operating systems (Windows, Mac, Linux), is housed on a user's hard drive (as compared to an internet interface), allows for batch processing of text files, and incorporates over 150 classic and recently developed indices related to text cohesion. The cohesion indices reported by TAACO evenly focus on local cohesion, global cohesion, and overall text cohesion. Local cohesion refers to cohesion at the sentence level (i.e., cohesion between smaller chunks of text) while global cohesion refers to cohesion between larger chunks of text (usually paragraphs). Overall text cohesion refers to the incidence of cohesion features in an entire text, but not in comparison to other parts of the text, such as lexical diversity across a text. Many TAACO indices incorporate a part of speech tagger from the Natural Language Tool Kit (Bird, Loper, & Klein, 2009) and synonym sets (synsets) from the WordNet lexical database (Miller, 1995).Indices reported by TAACO
Bird, S., Loper, E., & Klein, K. (2009). Natural Language Processing with Python. O'Reilly Media Inc.
Loxterman, J. A., Beck, I. L., & McKeown, M. G. (1994). The effects of thinking aloud during reading on students' comprehension of more or less coherent text. Reading Research Quarterly, 353-367.
Miller, G. A. (1995). WordNet: A Lexical Database for English. Communications of the ACM Vol. 38, No. 11: 39-41.
McNamara, D.S., Kintsch, E., Songer, N.B., & Kintsch, W. (1996). Are good texts always better? Interactions of text coherence, background knowledge, and levels of understanding in learning from text. Cognition and Instruction, 14, 1-43.
McNamara, D.S., & Kintsch, W. (1996). Learning from text: Effects of prior knowledge and text coherence. Discourse Processes, 22, 247-288.
McNamara, D.S., Louwerse, M.M., McCarthy, P.M., & Graesser, A.C. (2010). Coh-Metrix: Capturing linguistic features of cohesion. Discourse Processes, 47, 292-330.
To access TAACO please click on the following link: [LINK]