A Study Of English Reading Grading Based On Coh-Metrix Tools

Leveled Reading was raised by American scholars in 19th century,then it was widely accepted and continuously developed.Currently,Standards like Developmental Reading Assessment Levels,the Lexile Framework for Reading,Guided Reading Levels,Grade Level Equivalent,Basel Level and Degree of Reading Power are in widespread used in Occident.Though there are something difference between them,they also provide scientific references for parents,teachers and other educators.For English Language Learners,who not only keep interests of English,but also improve their English step by step,if they choose the reading books appropriately.However,they are not appropriate for Chinese English learners,because they are designed for native English speakers.Coh-Metrix was developed,refined and tested at the University of Memphis in the United States.It is a computational tool that provides a wide range of language and discourse measures,and a scientific approach to evaluate texts,which is useful to either English learners or researchers.In this paper,we use the results of Coh-Metrix,select the representative indices(Text Easability Principal Component Scores,Referential Cohesion,Syntactic Complexity,Readability)in accordance with the measurement of reading difficulty,and then develop the Computer Aided Learning(CAL)prototype system.For one thing,it could help the examinees prepare TOEFL reading.For another,the method could be improved and popularized as readings changed by users.For instance,teachers could help students in the same way with English readings,so as to obtain considerable real statistical data,then truly realized the Computerized Adaptive Testing System.