Table 1 The six discourse components and linguistic features

Word length

The total number of words found in the text is calculated using the output from the Charniak parser that generates a parse tree with part of speech tags for clauses, phrases, words, or punctuations.

Narrativity

The text tells a story with characters, events, places, and things that are familiar to a reader. Stories are basically about everyday oral conversation.

Syntactic simplicity

This component shows the degree to which the sentences in the text contain fewer or more words with the uses of simple, familiar or complex, unfamiliar syntactic structures.

Word concreteness

Content words are concrete, meaningful, and simple to understand. Abstract words are difficult to represent visually, so the texts that have a lot of abstract words tend to be more challenging than those content words.

Referential cohesion

Higher referential cohesion tends to have words and ideas that extend beyond sentences and the entire text. Lower cohesion is typically more difficult to process or connect the ideas together.

Deep cohesion

This component reflects the degree to which the text contains causal and intentional connectives that help a reader to have a more coherent and deeper understanding of events, processes, or actions in the text.