Editing Readability (section)

=== Lexico-semantic ===
The type-token ratio is one of the features that are often used to captures the lexical richness, which is a measure of vocabulary range and diversity. To measure the lexical difficulty of a word, the relative frequency of the word in a representative corpus like the [[Corpus of Contemporary American English]] (COCA) is often used. Below includes some examples for lexico-semantic features in readability assessment.<ref name="Computational assessment of text re" />
*Average number of syllables per word
*Out-of-vocabulary rate, in comparison to the full corpus
*Type-token ratio: the ratio of unique terms to total terms observed
*Ratio of function words, in comparison to the full corpus
*Ratio of pronouns, in comparison to the full corpus
*Language model perplexity (comparing the text to generic or genre-specific models)