Lexical density and readability: A case study of English textbooks

known as Active Skill for Reading (Anderson, 2003a, 2003b, 2003c, 2003d) at elementary, preintermediate, intermediate and upper-intermediate levels. The study applied three methods in determining lexical density and readability as proposed by Halliday (1985), Ure (1971) and Flesch (1948). The analysis revealed that three of the four reading texts were of high lexical density, apart from the text for upper-intermediate level. In terms of readability, the levels of texts corresponded to readability levels. However the highest level did not entail the topmost readability. There was little evidence of an increase of lexical density and readability in accordance with the increase of text levels as well as little indication relating to the connections between text levels, readability and lexical density. With reference to the methods employed, Halliday’s measurement of lexical density - based on the clause - had a significant correlation with Ure’s measurement, and a medium relation with Flesch’s Reading Ease Scale, whereas Ure and Flesch’s formulas showed no correlation.