Vocabulary Size

A large number of variables influence the way a learner comprehends a reading passage, one of which is vocabulary size. The studies which have focused on this seemingly important aspect, in some settings, are few and far between. This indicates the importance of running more research in this respect. The present study endeavored to examine this variable to discover its effect on reading comprehension ability of Iranian EFL learners. In so doing, 83 Iranian first-year university students (22 males and 61 females) were given a vocabulary size test (Nation 1990) and a reading comprehension test (TOEFL version 2004). The results showed a very significant correlation between vocabulary size and reading comprehension (r = .84, p < .05), which points out the necessity of improving the learners' vocabulary size in coping with reading passages. However, the high correlation found in this study calls for more replications to add to the precision of such a relationship.

This document reports on an ongoing project to develop the Global Scale of English (GSE) Vocabulary for Young Learners, a graded lexical framework for EFL learners aged 6 to 11. The framework is aligned to the GSE and the Common European Framework of Reference for Languages (CEFR; Council of Europe, 2001). This project follows up on a previous study carried out to identify vocabulary targets of adult learners of English (Benigno & De Jong, 2017, available at https://prodengcom.s3.amazonaws.com/GSE-Vocab.pdf and, together with the GSE Learning Objectives for Young Learners, aims to help teachers identify pupils’ learning targets at increasing levels of proficiency.

This study aims to tackle an answer to the main question; if there is a relationship between the vocabulary size of adult English language learners and their morphological awareness and if their performance would differ in word complexity. The participants were 90 senior BA English Language and Literature students from Jordanian universities. The two empirical research tools were the Vocabulary Size Test and Morphological Awareness Test. The results revealed the mid-frequent level vocabulary size of the participants, and they were unable to form and use new words using morphemes. A positive correlation between the vocabulary size of the participants and their morphological awareness existed. Besides, a positive relationship existed between their performance on word complexity and their morphological knowledge. Pedagogical solutions need to be implanted in English as a Second Language (ESL)/ English as a Foreign Language (EFL) classes.

The relative frequency of occurrence of words in language has been shown to have extremely powerful effects on perceptual and cognitive processes used in word recognition and lexical access. Although different theories of word perception account for the effects of word frequency with different mechanisms,
all current theories assume that a mental representation of the experienced frequency of words exists in some form in the lexicon. However, except for published norms of word frequency counts, no data are available on the familiarity of words. Thus, it is quite important to measure the judged
familiarity of words to develop a database of experienced frequency information that would give researchers more precise control of word frequency in perceptual and memory experiments. The present study collected familiarity ratings and response times for 20,000 words in the Mirriam-Webster Pocket
Dictionary. Summary statistics on these data are reported. These findings support the claim that although rated word familiarity and frequency counts are related, they are by no means equivalent. This database of familiarity ratings therefore provides a more valid estimate of the psychological correlate of word frequency than computational analyses of corpora of text. In addition, these familiarity data can be used to provide more direct estimates of the size of the mental lexicon than have been made by previous studies.

Evaluating learners’ vocabulary sizes and their textbooks is of major importance. Measurement of vocabulary size in this study was conducted with a vocabulary size test (Nation & Beglar, 2007). Data collected from the test scores revealed that the students from vocational colleges had a low receptive vocabulary size. Input from the textbooks was analyzed by using the Range program (Heatley, Nation, & Coxhead, 2002). The results showed that learners who completed this series of textbooks would only encounter 1,020 of the most frequently used word families, which indicate that the textbooks that the participants are using are not matched with their vocabulary size. Teachers, as well as material writers, should take students’ vocabulary sizes into account. Adding supplementary reading materials is proposed, as is instruction in active vocabulary learning strategies. In addition, deliberate learning of word lists and paying more attention to frequently-used words are also recommended.

Swadesh list, revisited. Leipzig-Jakarta list.
We offer a list of 100 words best kept across many linguistic families. We propose that the reconstruction of further linguistic families should begin with these words, who form the core of the vocabulary

Word Associates Format (WAF) tests are often used to measure second language learners' vocabulary depth with a focus on their network knowledge. Yet, there were often many variations in the specific forms of the tests and the ways they were used, which tended to have an impact on learners' response behaviors and, more importantly, the psychometric properties of the tests. This paper reviews the general practices, key issues, and research findings that pertain to WAF tests in four major areas, including the design features of WAF tests, conditions for test administration, scoring methods, and test-taker characteristics. In each area, a set of variables is identified and described with relevant research findings also presented and discussed. Around eight topics, the General Discussion section provides some suggestions and directions for the development of WAF tests and the use of them as research tools in the future. This paper is hoped to help researchers become better aware that the results generated by a WAF test may vary depending on what specific design the test has, how it is administered and scored, and who the learners are, and consequently, make better decisions in their research that involves a WAF test.

The purpose of the study was to investigate the reliability and validity of the monolingual version of the VST using a Classical Test Theory approach, based on data from a sizeable group of high intermediate and advanced Swedish learners of English. An additional purpose was to also use the test in a longitudinal design in order to investigate learners’ vocabulary size development over time.

A total of 198 participants took part in the study. They were all university-level, full-time students of English at a university in southern Sweden. The great majority (n = 151) had just started their first term of study; students in their second term of study (n = 22) also sat the test, as did students in their third term of study (n = 25). The test was a paper-and-pencil version of the 140-item monolingual (English) Vocabulary Size Test. The test version used can be found in Nation & Beglar (2007) and Schmitt (2010).

The VST seems capable of yielding reliable scores, but some items are in need of revision; a difficulty continuum based on target word frequency is visible but with some anomalies; VST scores correlate highly with VLT scores (another widely used vocabulary size test); Classical Test Theory approaches to validation suffer from sample dependence; over a period of 4.5 months, Swedish university students of English increased their mean vocabulary size by 648 word families; there is a need for further validation studies that investigate whether learners truly know the proportion of words from the target domain to the extent suggested by VST scores.

The present study investigates the effect of lexical difficulty, as measured by frequency, on reading comprehension and recall. It also estimates the relationship between vocabulary size, vocabulary depth, reading comprehension, and recall. To this end, 80 English as a foreign language (EFL) undergraduate university students are administered three standardized instruments including two vocabulary tests and a reading comprehension test. The latter comprises two similar passages (in terms of length and topic) one of which is adjusted by replacing 18% of its words by their low-frequent synonyms, and both passages are estimated lexically to measure their difficulty. Paired samples t-test results show that comprehension and recall are significantly low (p<.001) in the modified passage. This finding further confirms that lexical frequency measure is an effective estimate in determining reading material difficulty. Furthermore, for the second objective, Pearson product-moment analysis reveals a significantly high correlation between size and comprehension, a moderate to low correlation between depth and comprehension, and a moderate correlation between depth and recall tasks. Consequently, the study sugguests estimating the complexity of EFL reading academic material with lexical difficulty measure using frequency criterion to cope with students' reading deficiencies, and encourage explicit lexical instructions at EFL undergraduate university levels mainly.

This study investigates the size and depth of vocabulary knowledge and its relationship to the general language proficiency of EFL learners. The study sample included 120 students from the University of Bahrain. The sample was randomly selected from the student population and split into two groups in terms of their level of English: intermediate and advanced. The study aims to answer four questions: (1) What is the effect of general language proficiency on the sizes of the receptive and productive vocabularies of learners of English at the University of Bahrain? (2) How does general language proficiency affect the depth of vocabulary knowledge of learners of English at the University of Bahrain? (3) What is the relationship between receptive and productive vocabularies and the depth of vocabulary knowledge? and (4) What is the relationship between vocabulary size and the nature of lexical networking? All the students in the sample completed three vocabulary tasks. The first two tasks were Meara and Jones's Eurocentres Vocabulary Size Test (1990) and Meara and Fitzpatrick's Lex30 word association task (2000), which were used to measure the sizes of receptive and productive vocabularies. The third task was Gyllstad's COLLEX test (2007), which was used to investigate the depth of vocabulary knowledge. A quasi-experimental approach was adopted using a quantitative approach to analyze the data. The data of the study were analyzed by comparing the results of the two groups in relation to the three tasks using SPSS 16.0. The findings of the study have revealed that general language proficiency has a positive effect on learners' receptive vocabulary size, a moderate effect on learners' productive vocabulary size, and a very low effect on the depth of vocabulary knowledge. In addition, no relationship was shown between the size of vocabulary and the nature of lexical networking. With reference to these results, pedagogical and future research recommendations are made.

The study employed descriptive-quantitative research design which aimed to investigate the mean vocabulary size and mastery level of English department students. The subjects of the study were the first-year students majoring in English education department at Kutai Kartanegara University. Thirty-three students employed in this study were given the Vocabulary Levels Test (VLT) to measure their English vocabulary size as well as their mastery level. The findings of this study revealed that the students only knew about 1,273 word families. The result was still below the threshold as suggested by the vocabulary scholars and was not improved after years of learning. The finding also showed that the participants had a very low mastery level. They did not even master the 2,000 or 3,000 high frequency word level, nor the academic vocabulary level. The results indicate that the participants had a low vocabulary proficiency and suggest the future research to focus on investigating the vocabulary learning and instruction strategies that are effective to develop the students " high frequency words and academic words.

This paper describes a new vocabulary levels test (NVLT) and the process by which it was written, piloted, and edited. The most commonly used Vocabulary Levels Test (VLT) (Nation, 1983, 1990; Schmitt, Schmitt, & Clapham, 2001), is limited by a few important factors: a) it does not contain a section which tests the first 1,000-word frequency level; b) the VLT was created from dated frequency lists which are not as representative as newer and larger corpora; and c) the VLT item format is problematic in that it does not support item independence (Culligan, 2015; Kamimoto, 2014) and requires time for some students to understand the directions. To address these issues, the NVLT was created, which can be used by teachers and researchers alike for both pedagogical and research-related purposes.

Learning vocabulary has always been a major concern for language learners. The current research was implemented to find out the kinds of Vocabulary Learning Strategies (popular, somehow popular, and unpopular) in Schmitt’s new taxonomy (DET, SOC, COG, MEM, MET) used by English-major students. Fifty advanced English-major students at Shahid Bahonar University of Kerman participated in this study. To this purpose, Schmitt’s Vocabulary Learning Strategies Questionnaire (VLSQ) and the last level of his Vocabulary Levels Test (VLT) were used as the instruments. It was found that MEM was the most frequently used category and SOC the least frequently used one. Furthermore, COG, DET, and MET were the second, third and fourth categories respectively. The results of the study can be used by various people involved in language education including materials developers, language teachers, administrators, and other stakeholders.

This paper provides and explains the criteria by which the first eight 1,000-word frequency bands of the Japanese bilingual Vocabulary Size Test (VST) were revised. The VST (Nation & Beglar, 2007) was designed as a measure of vocabulary size for language learners. It was originally produced and validated in a monolingual format, but in recent years several bilingual versions have also been made. These variants may yield more accurate results, because they avoid conflating vocabulary knowledge with ability to decode answer choices in the L2. However, they have received little scrutiny beyond initial piloting and may therefore benefit from further examination and refinement (Nguyen & Nation, 2011). This paper describes the revision of the first eight 1,000-word frequency bands of the Japanese bilingual VST with the goal of increasing the test’s unidimensionality and accuracy. The revisions (a) removed English loanwords from the answer choices to prevent examinees from correctly respon...

Measuring students’ lexica is time-consuming, as one sitting of the
Vocabulary Size Test (VST) usually takes 40-60 minutes. As a result,
teachers would benefit from being able to make reasonable estimates from
commonly available information. This paper aims to investigate: (1) What
are the mean vocabulary sizes of students at Japanese universities as a
whole, and by university department (hensachi)? and (2) Are a university’s
department standardized rank scores (hensachi) a useful proxy for English
vocabulary size? This study used a cross-sectional design where 3,449
Japanese university students were tested using Nation and Beglar’s VST.
The results showed an average score of 3,715.20 word families and that
VST scores were significantly higher for students in higher department
hensachi programs. This current department hensachi was also found to
have a stronger correlation with VST scores than with other covariates
when the entire sample was considered. Lastly, there appears to be a
lack of consistent knowledge of the most frequent words of English,
suggesting that curriculum designers at Japanese universities should focus on teaching high-frequency English words. Although the findings support the use of the VST for comparing receptive written vocabulary knowledge between learners, they perhaps do not support its use in establishing a vocabulary size to decide lexically appropriate materials.

Modern estimates of English native speaker vocabulary size have concentrated on acquisition in childhood (e.g. Biemiller & Slonim, 2001) and among undergraduates (e.g. Milton & Treffers-Daller, 2013). There seems to be an assumption that vocabulary size is pretty stable in adults and that the estimates for undergraduates are likely to be applicable to the broader population, at least until age related decline begins sometime after the age of about 60 (Burke & MacKay, 1997). The study reported in this paper examines a cross-section of adults aged from 20 to over 60, and from graduate and non-graduate populations. The results suggest that the graduate population has a marginally larger vocabulary size than the non-graduate population and it is speculated that the difference is probably too small, and the vocabulary sizes too large, to drive educational differences. The graduate population also differs from the non-graduate In the graduate population vocabulary size appears to continue to grow with age, but while vocabulary size scores vary in the non-graduate population, the differences noted are not statistically significant after the age of 30. Unauthenticated Download Date | 4/26/17 11:33 AM

Based on an analysis of the literature and a large scale crowdsourcing experiment, we estimate that an average 20-year-old native speaker of American English knows 42,000 lemmas and 4,200 non-transparent multiword expressions, derived from 11,100 word families. The numbers range from 27,000 lemmas for the lowest 5% to 52,000 for the highest 5%. Between the ages of 20 and 60, the average person learns 6,000 extra lemmas or about one new lemma every 2 days. The knowledge of the words can be as shallow as knowing that the word exists. In addition, people learn tens of thousands of inflected forms and proper nouns (names), which account for the substantially high numbers of 'words known' mentioned in other publications.

This study investigates the size and depth of vocabulary knowledge and its relationship to the general language proficiency of EFL learners. The study sample included 120 students from the University of Bahrain. The sample was randomly selected from the student population and split into two groups in terms of their level of English: intermediate and advanced. The study aims to answer four questions: (1) What is the effect of general language proficiency on the sizes of the receptive and productive vocabularies of learners of English at the University of Bahrain? (2) How does general language proficiency affect the depth of vocabulary knowledge of learners of English at the University of Bahrain? (3) What is the relationship between receptive and productive vocabularies and the depth of vocabulary knowledge? and (4) What is the relationship between vocabulary size and the nature of lexical networking? All the students in the sample completed three vocabulary tasks. The first two task...

Bilingual learners' inadequate English vocabulary size is one of the most frequently stated problems in applied linguistics. Using mostly qualitative case studies, earlier findings reported several factors (e.g. negative attitude, lack of exposure, poor proficiency, and age of acquisition) as related to bilingual learners' insufficient English vocabulary size. Therefore, the present study undertakes an in-depth quantitative study to measure language dominance, which encompasses language history, use, proficiency, and attitude towards Malay, the first language (L1), and English, the second languages of 96 Malay-English bilingual undergraduates. It also examines the relationship between vocabulary size and overall dominance scores. The 20,000 Vocabulary Size Test was used to measure English vocabulary size and the Bilingual Language Profile (BLP) was used to determine the dominance score. The results show that most of the Malay-English bilinguals are Malay dominant. A positive and statistically significant association was found between the overall language dominance score and English vocabulary size. One of the most striking findings to emerge from this study is that the language dominance score accounts for 30% of the variability in the vocabulary size of Malay-English undergraduates.

This s tudy inves tiga tes the effect of using a bigger vocabula ry size in oral class room presenta tions on the speaking profi cie ncy of students in English as a forei gn langua ge. The s tudy was conducted with 30 freshman s tudents doing thei r lis tening and speaking course in Semnan Uni versi ty. For the enti re course of 12 weeks , the s tudents in the experimental group were asked to present thei r productions in terms of the voca bula ry they employed, whi ch was also the focus of the tea cher's evalua tion in ea ch session. At the end of the course, they were interviewed for thei r profi ciency in speaking. The des cripti ve and inferential calculations were done based on a modi fied version of an oral profi ciency i nterview s cale sugges ted by Penny Ur. The answers were recorded and thei r fluency and a ccura cy were graded. The resul ts sugges t tha t s tudents wi th a voca bula ry-ri ch producti on improved thei r speaking profi ciency in English more than other students did.

This action based research pilot study examines the changes in receptive written vocabulary size (VS) of N= 42 English language learners participating in uncoordinated university-wide reading courses over a 15-week semester. Employing the Vocabulary Size Test of the New General Service List as a pre-post test instrument to measure vicissitudes over a semester, results indicate statistically significant variations (p < .05) within two of three groups examined in this study: beginner, intermediate, upper. This paper examines pedagogy when rationalizing improvement or regression in VS or vocabulary knowledge amongst practitioners' approaches to facilitating the reading course. This research provides English language educators with insight in relation to increasing vocabulary sizes as well as an exploration of pedagogical implications and praxis when facilitating a university reading course to English learners.

Vocabulary plays a crucial role in foreign language learning, and vocabulary mastery proves to be challenging at different competence levels. Compared to other areas of research into Chinese as a foreign language, vocabulary acquisition and vocabulary teaching have rarely been investigated. The aim of this study is to investigate the relationship between vocabulary learning strategies and vocabulary size and to verify whether vocabulary size is positively correlated to proficiency level. A total of 95 Italian undergraduate Chinese learners, from elementary to intermediate levels, participated in this study. The participants were first given a vocabulary learning questionnaire and then a vocabulary size test. Statistical and qualitative analyses of the data revealed two trends: a poor variety of vocabulary learning strategies and a positive correlation between vocabulary size and proficiency level.

This article presents preliminary results from research funded by a 2012 JALT research grant (for details, McLean, 2012). Research on the vocabulary size of Japanese students is limited. Shillaw (1995), and Barrow, Nakanishi & Nishino (1999) suggest that the vocabulary size of non-English major Japanese university students is around 2,300 words. In these studies vocabulary knowledge was assessed over a limited range of word families, with students completing self-checking familiarity surveys. However, this approach may have measured the word forms students recalled being exposed to, or their ability to discern real English words from nonsense words, rather than measuring receptive reading vocabulary knowledge.

This study investigates the size and depth of vocabulary knowledge and its relationship to the general language proficiency of EFL learners. The study sample included 120 students from the University of Bahrain. The sample was randomly selected from the student population and split into two groups in terms of their level of English: intermediate and advanced. The study aims to answer four questions: (1) What is the effect of general language proficiency on the sizes of the receptive and productive vocabularies of learners of English at the University of Bahrain? (2) How does general language proficiency affect the depth of vocabulary knowledge of learners of English at the University of Bahrain? (3) What is the relationship between receptive and productive vocabularies and the depth of vocabulary knowledge? and (4) What is the relationship between vocabulary size and the nature of lexical networking? All the students in the sample completed three vocabulary tasks. The first two task...

Important note about size and levels tests Measuring vocabulary size and interpreting vocabulary size test scores Vocabulary size tests are intended to estimate the total number of words a learner knows. This estimate can be useful when comparing groups of learners, measuring long-term vocabulary growth, or providing “one kind of goal for learners of English as a second or foreign language” (Nation, 2013, p. 522). The Vocabulary Size Test (VST) (Nation & Beglar, 2007), for example, is a measure of written receptive word knowledge based on word family frequency estimates derived from the spoken subsection of the BNC (Nation, 2006). Each item on the VST presents the target word first in isolation followed by a non-defining context sentence, with four answer-choices presented in either English or in the learners’ L1. Results of the VST among samples with a wide range in ability have shown that the test is able to reliably distinguish between learners of different vocabulary proficiency...

Vocabulary size (VS) and English language proficiency (ELP) are acknowledged as important factors in students' overall cumulative grade point average (CGPA) in tertiary education. This study attempts to investigate the associations among vocabulary size, ELP, and CGPA. It also determines whether vocabulary size or ELP can better predict tertiary students' CGPA. The study sample is comprised of 96 undergraduates on four programs at a Malaysian public university. The students' vocabulary size was measured using a 20,000-word vocabulary size test, their ELP that was derived from their Malaysian University English Test scores, and their CGPA that was obtained from their academic transcripts. The correlational, comparative, and predictive analyses revealed a moderate and significant positive association among all the variables. In addition, vocabulary size emerged as a better predictor of CGPA than ELP, with a contribution of 25% to overall CGPA. The findings provide strong empirical confirmation demonstrating the significant function of vocabulary size in tertiary students' CGPA. As a result of these investigations, suggestions were identified for future research.

This paper offers a response to Hutchinson's comments on our preliminary report of ''I don't know'' use and guessing on the bilingual Japanese Vocabulary Size Test (VST), which was published in Vocabulary Learning and Instruction. In particular, it provides greater clarification of the English proficiency levels used throughout that paper and a reiteration of what we see as its key findings regarding the range of vocabulary size estimates that were able to be calculated for the participants. Finally, it addresses the methodological limitations of the original study, which, we believe, reduce any determinations about the participants' personality types or general test-taking behaviors to mere speculation.

Many researchers have tried to assess the number of words adults know. A general conclusion which emerges from such studies is that vocabularies of English monolingual adults are very large with considerable variation. This variation is important given that the vocabulary size of schoolchildren in the early years of school is thought to materially affect subsequent educational attainment. The data is difficult to interpret, however, because of the different methodologies which researchers use. The study in this paper uses the frequency-based vocabulary size test from Goulden et al (1990) and investigates the vocabulary knowledge of undergraduates in three British universities. The results suggest that monolingual speaker vocabulary sizes may be much smaller than is generally thought with far less variation than is usually reported. An average figure of about 10,000 English word families emerges for entrants to university. This figure suggests that many students must struggle with th...

This article investigates the cross-linguistic comparability of the newly developed lexical assessment tool Cross-linguistic Lexical Tasks (LITMUS-CLT). LITMUS-CLT is a part the Language Impairment Testing in Multilingual Settings (LITMUS) battery (Armon-Lotem, de Jong & Meir, 2015). Here we analyse results on receptive and expressive word knowledge tasks for nouns and verbs across 17 languages from eight different language families: Baltic (Lithuanian), Bantu (isiXhosa), Finnic (Finnish), Germanic (Afrikaans, British English, South African English, German, Luxembourgish, Norwegian, Swedish), Romance (Catalan, Italian), Semitic (Hebrew), Slavic (Polish, Serbian, Slovak) and Turkic (Turkish). The participants were 639 monolingual children aged 3;0-6;11 living in 15 different countries. Differences in vocabulary size were small between 16 of the languages; but isiXhosa-speaking children knew significantly fewer words than speakers of the other languages. There was a robust effect of w...

This article investigates the cross-linguistic comparability of the newly developed lexical assessment tool Cross-linguistic Lexical Tasks (LITMUS-CLT). LITMUS-CLT is a part the Language Impairment Testing in Multilingual Settings (LITMUS) battery (Armon-Lotem, de Jong & Meir, 2015). Here we analyse results on receptive and expressive word knowledge tasks for nouns and verbs across 17 languages from eight different language families: Baltic (Lithuanian), Bantu (isiXhosa), Finnic (Finnish), Germanic (Afrikaans, British English, South African English, German, Luxembourgish, Norwegian, Swedish), Romance (Catalan, Italian), Semitic (Hebrew), Slavic (Polish, Serbian, Slovak) and Turkic (Turkish). The participants were 639 monolingual children aged 3;0-6;11 living in 15 different countries. Differences in vocabulary size were small between 16 of the languages; but isiXhosa-speaking children knew significantly fewer words than speakers of the other languages. There was a robust effect of w...

This article investigates the cross-linguistic comparability of the newly developed lexical assessment tool Cross-linguistic Lexical Tasks (LITMUS-CLT). LITMUS-CLT is a part the Language Impairment Testing in Multilingual Settings (LITMUS) battery (Armon-Lotem, de Jong & Meir, 2015). Here we analyse results on receptive and expressive word knowledge tasks for nouns and verbs across 17 languages from eight different language families: Baltic (Lithuanian), Bantu (isiXhosa), Finnic (Finnish), Germanic (Afrikaans, British English, South African English, German, Luxembourgish, Norwegian, Swedish), Romance (Catalan, Italian), Semitic (Hebrew), Slavic (Polish, Serbian, Slovak) and Turkic (Turkish). The participants were 639 monolingual children aged 3;0–6;11 living in 15 different countries. Differences in vocabulary size were small between 16 of the languages; but isiXhosa-speaking children knew significantly fewer words than speakers of the other languages. There was a robust effect of w...

The Vocabulary Size Test (VST) was created to provide a reliable estimate
of a second language learner’s written receptive vocabulary size, measuring from the most frequent fourteen 1,000 word families of the spoken
subsection of the British National Corpus. While some have recommended
that users should limit the amount of the test taken to only slightly
above a student’s level, others argue that learners should take every
level of the test. However, this raises concerns that correct responses
on lower frequency levels could largely be attributed to guesses rather
than vocabulary knowledge. In this paper we analyze a data set of
3,373 Japanese university students’ responses to the first eight levels of
the original VST under the 3PL model, in order to determine the
minimum expected score on the test for learners of low ability, examine
the proportion of low-level students’ scores on the lowest frequency level
tested that can be attributed to guessing under the 3PL model, and
conduct a model fit comparison to determine whether the 3PL model
offers a significantly better description of the data than the Rasch model.
The results indicate that a substantial portion of lower level learners’
scores on items testing low-frequency words can be attributed to guessing
and support the position that students should not sit every level of the
test. The authors recommend using the results of the 3PL analysis in
order to determine which sections of the test learners of different
proficiency levels should sit.

This article analyses how a set of psycholinguistic factors may account for children’s lexical development. Age of acquisition is compared to a measure of lexical development based on vocabulary size rather than age, and robust regression models are used to assess the individual and joint effects of word class, frequency, imageability and phonological neighbourhood density on Norwegian children’s early
lexical development. The Norwegian Communicative Development Inventories (CDI) norms were used to calculate each CDI word’s age of acquisition and vocabulary size of acquisition. Lexical properties were downloaded from the lexical database Norwegian Words, supplemented with data on frequency in adult and child-directed speech. Age of acquisition correlated highly with vocabulary size of acquisition, but the new measure was more evenly distributed and more sensitive to lexical effects. Frequency in child-directed speech was the most important predictor of lexical development, followed by imageability, which seems to account for the dominance of nominals over predicates in
Norwegian.