語彙力と実用コミュニケーション能力の関係

抄録

The objective of this paper was to observe and examine the dynamic relationship between learners'"vocabulary size" and "communicative proficiency", as measured by the TOEIC test. First, we defined three levels of vocabulary size based on "The System 5,000 Word List", a word frequency list: 1,000 word list, 3,000 word list, and 5,000 word list. Then, the TOEIC tests were modified to make three tests comparable to the three defined levels of vocabulary size. Modifications to the TOEIC tests were made by deleting words from the tests that were not found on each level's defined list. The tests were administered to a group of native speakers of English. The vocabulary coverage coefficient of each participant was calculated and then compared with each participant's TOEIC score. There appears to be a relationship between the vocabulary coverage coefficient and the TOEIC scores in this study. This relationship may indicate that this coefficient may act as a predictor of TOEIC scores with a negligible margin of error. In other words, vocabulary size provides an objective measure of a learner's communicative proficiency, when all factors are held constant with the exception of vocabulary knowledge. It was also found that native speakers, who utilized top-down processing of information on the TOEIC tests, scored higher than 700 with the test of 1,000 words, and higher than 900 with the test of 3,000 words.