Collocation frequency as a readability factor

A readability measure that can reliably estimate the difficulty level of sample texts has great potential in ESL teaching. We argue for the inclusion of collocation frequency as a generic factor in estimates of ESL text readability, since the readability of any text will be affected adversely by the presence of collocations. Collocational word combinations are seldom amenable to comprehension solely on the basis of acquaintance with individual word components, so they present particular difficulties for L2 learners. Our paper describes the measure of average collocation frequency, how this is derived from a reference corpus and can be applied as a factor in estimating textual readability. A software tool, based upon this approach, is presently in development.