An Investigation Of The Effect Of L2 Proficiency And Topic Familiarity On L2 Incidental Vocabulary Acquisition

Numerous theoretical descriptions and empirical studies have been accomplished on incidental vocabulary acquisition over several decades, but a few has taken into account the effects of reader-based factors on IVA. Therefore, to further explore incidental vocabulary learning, the present study attempted to examine the effects of two reader-based factors, i.e., topic familiarity and second language proficiency, on IVA through reading expository passages.The present study consisted of six chapters. Chapter one introduced the background, significance and aims of this study. Chapter two reviewed the theories and studies on IVA, IVA and reading, the effects of reader-based factors on IVA in reading and text types. Chapter three was the theoretical foundation of this study, definitions of key terms and specific introductions to interactive reading and study by Pulido (2003) included. Chapter four described the research methodology in details, including research questions, participants, reading materials, target words, measures of variables and research procedures. 186 learners attended the whole study (data completed by 90 of them were valid) without any indication of vocabulary tests. Definition production and selection tasks, containing all 16 nonsense TWs, were adopted immediately and four weeks after reading (i.e., vocabulary gain and vocabulary retention). All data were analyzed via Multivariate with Post-hoc tests.Chapter five analyzed the data and discussed the results. From the data, we have got the following results: 1) Vocabulary can be acquired incidentally in reading expository passages; meanwhile, the independent variables of topic familiarity and second language proficiency exerted their positive effect on incidental vocabulary acquisition. 2) In both definition production and selection, topic familiarity kept a significant effect on incidental vocabulary gain rather than on vocabulary retention. However, incidental vocabulary acquisition both immediately and 28 days after reading were greater when participants read within more familiar expository passages in comparison to less familiar ones. 3) In definition production and selection, L2 proficiency has a significant effect on overall incidental vocabulary gain and retention, that is, as proficiency increased, total vocabulary gain and retention would significantly increase. 4) As for the interactive effects of topic familiarity and L2 proficiency, in definition production from familiar passages, L2 proficiency had a significant effect on vocabulary gain whereas it had no significant influence on vocabulary retention; In definition production from unfamiliar passages, L2 proficiency still had a significant effect on vocabulary gain while it had no significant effect on vocabulary retention; In definition selection from familiar passages, L2 proficiency kept a significant influence on incidental vocabulary gain and retention; In definition selection from unfamiliar passages, L2 proficiency did not have significant effect on vocabulary gain but it had on vocabulary retention. Nevertheless, no significant effect was found to be consistent among different proficiency groups in definition production and selection immediately and 28 days after reading. 5) As with the two vocabulary measures, it was found that participants can gain and retain more target words in definition selection than in definition production.Anyway, this study not only enriched and developed the researches into incidental vocabulary acquisition, but also it contributed to the practice of vocabulary teaching and learning. However, no research has no flaws, this research included. In order to perfect the study of this nature, firstly, time needed to complete the reading tasks should be considered for participants across different levels; secondly, if the comprehension of the reading gist could be accounted, different results may take place; lastly, morphological, syntactic, orthographic, and pragmatic features, apart from semantic features, can also be investigated in the study of the incidental vocabulary acquisition.