On the Relationships of Iranian EFL Learners’ Crystallized and Fluid Intelligences with Their Vocabulary Size
The aim of the present study was to investigate the relationship between the Iranian EFL Learners’ Crystallized and Fluid Intelligences with their Vocabulary Size. The participants included 100 male and female learners studying TEFL at the Islamic Azad University of Mashhad who aged between 20 and 40 years old. To administer the study, experimental and quantitative analysis was conducted, and the relationship between the variables was measured using three instruments namely, Baddeley’s (1968) Grammatical reasoning Test for Fluid Intelligence, Persian C-Test (2015) for Crystallized Intelligence, and Nation’s (2012) Vocabulary Size Test. The collected data was analyzed using SPSS 21. First, correlational analyses were conducted to find out the correlation coefficients between the variables. Then, multiple coefficient tests were employed to find the Beta weight of the variables. The results obtained from the correlational analyses displayed a significant relationship between Iranian EFL learners’ Crystallized Intelligence and their vocabulary size no significant relationship between Iranian EFL learners’ Fluid Intelligence and their vocabulary size. Additionally, regression analysis showed that the model consisting of both Crystallized and Fluid Intelligence explain a small but significant portion (8%) of the variance in vocabulary size. It was also concluded that Fluid Intelligence does not significantly predict learners' vocabulary size, yet Crystallized Intelligence significantly predicts the learners’ vocabulary size. Also, the study implies that Crystallized Intelligence should be considered in the language learners’ curriculum to achieve higher teaching and learning purposes.