Table 3.

Features of Coh-Metrix-Dementia

Latent semantic analysis (LSA)
Average between adjacent sentences	Mean of similarity between pairs of adjacent sentences present in the text
Standard deviation between adjacent sentences	Standard deviation of the similarity between the pairs of adjacent sentences present in the text
Average similarity between all sentence pairs in the text	Mean of similarity between all sentence pairs in the text, not just the adjacent pairs
Standard deviation between sentences, all sentence pairs	Standard deviation of similarity between all sentence pairs in text
Average between adjacent paragraphs	Average similarity between adjacent paragraphs in the text
Standard deviation between adjacent paragraphs	Standard deviation of similarity between adjacent paragraphs in the text
Mean givenness of sentences	Average similarity between each sentence and all the text that precedes it. Average givenness of each sentence of the text from the second sentence onward. If the text has only one sentence, the metric is set to 0.0. Givenness of a sentence is defined as the LSA similarity between the sentence and all the text that precedes it.
Standard deviation of sentences givenness	Standard deviation of the similarity between each sentence and all the text that precedes it. Standard deviation of the givenness of each sentence of the text from the second sentence onward. If the text has only one sentence, the metric is set to 0.0. The givenness of a sentence is defined as the LSA similarity between the sentence and all the text that precedes it.
Mean span of sentences	Mean span of each sentence of the text from the second onward. If the text has only one sentence, the metric is set to 0.0. The span of a sentence, as well as givenness, is a way of measuring the closeness between a sentence and the context that precedes it. The difference, in simple terms, is that span seeks to capture similarity not only with the explicit content presented earlier in the text but also with everything that can be inferred from that content.
Standard deviation of sentence span	The standard deviation of the span of each sentence of the text, from the second onward. If the text has only one sentence, the metric is set to 0.0.
Semantic density
Total idea density	Number of propositions present in the text, per every 10 words. For the calculation of the propositions, empty or disfluent propositions are not taken into account, and the calculation is done on the revised text for better performance of the extraction tool.