Several articles on Vorabulary

In vocabulary class i learned several things about vocabulary, like vocab size to listen and read in second langauge, testing the Vocab test itself, implication toward vocab teaching, and the like. Below are several article i read recently.

What seems to be famous among many people is the fact that at least 95%, preferably 98% of knownwords in a text (less than one word in two lines in a page) is needed to get the general understanding of the text in listening and reading.
Adolphs, S and Schmitt, N (2003) comments that to reach the level of more than 96% coverage, around 5000 words are needed to get general understanding in listening. It is a bit surprising because 3000 words have been believed enough to achieve the general understanding.

Chung, T,M and Nation,P(2003) Technical vocabulary in specialised texts (Reading in a Foreign Language 15(2) October 2003 assess the technical vocab in Applied linguistics texts and Anatomy texts and found that so many words are used as technical words which is also used as "normal" words in daily life. More than 1/3 is technical words in Anatomy texts and more than 1/6 is technical words in Applied linguistics texts!

Nation, P (2000) Learning vocabulary in lexical sets: Dangers and Guidelines.(TESOL journal 9(2) 6-10)cautions against teaching several words within thematically or semantically related category, like "fast" and "rapid" (near synonyms), "bed" and "sleep" (free association), and "dark" and "light" (opposites)! Because many teachers including me have taught related vocab at the same time, this strategy is harfmful to students unless they establish one word in their brains.

Laufer, B and Nation, P (1995) Vocabulary sixe and use: Lexical richness in L2 written production. (Applied Linguistics 16(3)) come up with useful measurement to assess a learner's lexical richness named LFP (Lexical Rrequency Profile). In this article, they measure the validity and reliablity of LFP. In validity analysis, they show that the higher his/her proficiency is, the upper level of frequency (i.e low frequency words rather than 1st 1000 words level), he/she tend to use. They also show that 2nd 1000 words level is the very "threshold" .Both of low proficiency and high proficiency uses a lot of words within the level. In reliability analysis, they reveal that two composition the same learner has smilar(not significantly different) LFP in each level of frequency. They beautifully succeed in demostrating the validity and reliability of LFP, though it is just i cannot find out any pitfalls.

Waring, R and Takaki, M (2003)At what rate do learners learn and retain new vocabulary from reading a graded reader? (Reading in a Foreign Language 15(2) October 2003) conduct really interesting reseach! They substitute artifical words to several existing words in a text, and research how much learners memorized those words in intermeidate post test, and three-months-later test.
Bu doing that, they tried to assess the exact degree learners keep them in their brain for a long time. Because those artificial words cannot been met any other place, they cannot be learned in other places! Their implication is also intruiguing! Based on the result of many many words forgotten after the three month, they succeed in casting a doubt toward extensive reading, though they do not say ER is useless. But the result clearly shows that new words are learned if the words are repeated again and again (In Laufer's lecture at TUJ last week, she also says that from 1 to 2 books, from 100 to 200 words need to be read per week. She said that in case study of Grabe and Stoller (1997), a learner named Bill learned only 350 words after 450 reading hour in 5 month! That's really frustrating!) (It is clear that a learner must read at least one graded reader in a week according as Nation,P and Wang, K (1999) says). Such exposure seems to be impossible in EFL environment like in Japan, i guess. Though ER is not just for learning a new word, but also for reinforcing already known words as they say, how intensive reading, and deliberate vocab learning should be incorporated into ER should be considered more.