Study On The Relationship Of Lexical Richness To The Quality Of Timed Writing

Lexical richness, as an illuminative predictor of learners'general language proficiency, has been attached great importance in recent decades. A number of empirical studies have been carried out to explore the diversity of vocabulary in written and spoken texts of second language learners. However, these studies have never reached a consensus on which dimensions should be applied to measure lexical richness.Based on the theories of Laufer (1991), Engber (1995) and Read (2000), a tentative conceptual framework of lexical richness has been constructed for the present research, which comprises three dimensions, namely, lexical variation, lexical sophistication and lexical density. Then the research efforts have been made to investigate the developmental features of the three dimensions and the relationships among them as well as their correlations with writing quality.The subjects of the current study are 120 students in English major from 4 intact classes from Year One to Year Four in a normal university, who are selected from a population of 135 students participating in the writing test. The data are based on the timed compositions written in the first semester of the academic year 2010-2011. These writings are measured in light of the above three dimensions with the help of such software as RANGE and SPSS.After analyzing the data obtained from the 120 subjects, the research yields the following findings:(1) In terms of lexical variation, the increase of lexical variation does not go in a linear way. Year Two and Year Four outperform Year One and Year Three. Besides, subjects from Year one through Year Four do not show salient differences.(2) Lexical sophistication, as the second measure of lexical richness, turns out to be the best factor in differentiating the writing competence of the subjects in four groups. On the whole, the frequency of using sophisticated words increases while the number of high frequency words decreases in the writings of these subjects as they further their study.(3) When it comes to lexical density, it does not rise in a leaner way accordingly. There is a decrease from Year One to Year Two, although an increase is shown from Year Two to Year Four. (4) A significant correlation between lexical variation and lexical sophistication is found while there exist non-significant correlations between lexical variation and lexical density and between lexical sophistication and lexical density.(5) Regarding the relation between lexical richness and writing quality, significant correlations are displayed between lexical sophistication and writing quality as well as between lexical density and writing quality. However, there is no statistically salient correlation between lexical variation and writing quality.The findings of present study have shed new light on learners'choice of vocabulary in their writings, thus exerting further implications on second language learning and teaching.