An International Comparative Studies On Text Readability Of Senior High School English Textbooks

The English textbook is an indispensable component of English teaching. And the difficulty of the textbook relates directly to the effectiveness of English teaching and learning. To verify whether one textbook is suitable for certain groups of learners or not, it’s necessary to evaluate the difficulty of the textbook. The evaluation of the textbook difficulty is a profound procedure that involves many factors. In this paper, the study only focuses on the text difficulty of the textbook. Rudolf Flesch’s (1948) Reading Ease formula is the most influential one among others, so this study will adopt it as the readability measurement software.The data are 10 sets English textbook of senior high school from 7 countries and region around the globe. Four of them are from Mainland China, and the other six are from France, Russia, Japan, Brazil, South Korea and Chinese Taiwan. It should be noted that not all the countries has the clear-cut or well-defined senior high school period as China. Only East Asian countries and region like Japan, South Korea and Chinese Taiwan has the similar period as China. So for the convenience of this comparative study, the similar or equivalent period in other countries are seen as same as the "senior high school period" in China. So are their corresponding textbooks. Chapter Three presents the basic ethnographic background behind the textbook and the features of textbook.The second chapter of this paper is literature review, which gives a brief account of the readability studies around the globe, including the origin and development of the readability study, and also the reliability and limitation of the readability formula. It also talks about the factors that may influence text difficulty. At last, it presents the orientation and availability of the readability study.The primary research objective is to compare the text difficulty among different textbooks. Besides Rudolf Flesch’s (1948) Reading Ease formula, this study also introduces other tools like Low Frequency Vocabulary Rate, Lexical density and genre analysis. In order to make this study more systematic and intuitional, the study integrated all these text difficulty indicators together into a Framework, namely Framework for Text Difficulty Analysis (FTDA). The FTDA not only lays the theoretical foundation for this study, but also provides a complete set of research method.The analysis of text difficulty is conducted from two dimensions, inter-textbook and intra-textbook. The former refers to the analysis across different sets of textbooks, which includes readability analysis, lexical density, low frequency vocabulary rate and genre analysis. The latter refers to the analysis within one set of textbook, which includes the readability trend and readability distribution analysis.In the inter-textbook section, the study is basically a comparative analysis on the macro level, so the basic unit of this study is "set" and the data here represent the quantitative and qualitative properties of the one whole set of textbook. The innovation of the Unreadability Rate (UR) makes it possible that the readability score can be integrated with Low Frequency Vocabulary Rate (LFVR) and Lexical density (LD). As an integration of three text difficulty indictors, it provides a more comprehensive coverage of the physical properties of the text relating to difficulty. This integration is named as "Integrated Text Difficulty Rate" (ITDR) for convenience.In the intra-textbook section, the analysis is conducted on the micro level, and the quantitative properties of every individual text in one set will be examined. The first method is Readability Trend. It is a method to compare the beginning part with the ending part of textbook and SPSS is employed to compare the mean readability score of the first 15 texts and last 15 ones of the each set of textbook. The second method is Readability Distribution, and it is consisted of two parts:Difficulty Text Rate (DTR) and Difficulty/Easy Ratio. DTR simply represents the rate of difficult text in each set of textbook. Difficulty/Easy Ratio is the ratio between difficulty text rate and easy text rate.Chapter Six will combine the statistical result with the actual text in textbook.In order to ensure the validity of the study, it also includes a triangulation part presented in Chapter seven, which involves three related perspectives, namely readability score, lexical density and students’ actual reading performance, to further enhance the reliability of this study. First, a survey is designed, which combines reading test and after-test questionnaire and acquires data from 93 senior high school graduates, to explore the correlation between the readability score and students’ actual reading experience, by comparing the actual test score and their subjective perception of test material’s difficulty. The reading test materials are selected from these 10 sets of textbooks. It is worthwhile to notice that, this chapter has its own independent methodology, study design, analyzing method and result that is different from those of Chapter four and five, so to maintain the coherence of the paper, this triangulation procedure will be an independent and self-contained chapter placed at end of the paper.The key finding of this study included the overview of the text difficulty in ten sets of textbook, along with the triangulation that proved readability as a reliable text difficulty indicator. The multiple methods applied in this study was valuable not only for the rich data it gathered during the research process, but also for the validation of these methods, making them the useful tools in pedagogical application. The Framework for Text Difficulty Analysis, though deriving from this study, has the potential to extend its range of application for more studies.