Estimating root word vocabulary growth in normative and advantaged populations: Evidence for a common sequence of vocabulary acquisition.

Abstract

Root word vocabulary was studied in 2 normative samples (English-speaking, wide socioeconomic range) and in an advantaged sample. The authors estimated that in 2nd grade, the mean normative vocabulary was 5,200 root words, increasing to approximately 8,400 root words by 5th grade. During grades 3-5, the lowest quartile added about 3 root words a day, whereas the highest quartile added about 2.3 words a day. However, by 5th grade, children in the lowest quartile had only reached average 4th-grade level because they had such a small vocabulary in 2nd grade. There is evidence that words are learned in roughly the same order. The implications of these findings suggest (a) that greater efforts should be made to foster vocabulary acquisition in the primary years and (b) that a rough vocabulary curriculum sequence can be identified for the elementary years.Increasingly, educators are becoming aware of the importance of vocabulary development as an aspect of successful educational achievement. For example, Gough and Tunmer's (1986) "simple view of reading" emphasizes the combined importance of identifying words and understanding language for successful reading. Catts, Fey, Zhang, and Tomblin (1999) reported that language as well as phonological problems must be considered when working with poor readers. Cunningham and Stanovich (1997) reported that vocabulary assessed in first grade predicted over 30% of reading comprehension variance in 11th grade. Conversely, recent studies of early reading intervention such as Pinnell,

Age-of-acquisition ratings for 30,000 English words

“…1. This null effect in subjective judgments of AoA is surprising, given the wealth of developmental literature showing that early advantages in vocabulary size (e.g., larger numbers of word types learned earlier) are excellent predictors of future educational achievements (e.g., Biemiller & Slonim, 2001). AoA correlated strongly with word frequency, and the relationship was log-linear (see below).…”

The Influence of Reading on Vocabulary Growth: A Case for a Matthew Effect

“…For example, Biemiller and Slomin (2001) reported that in the second grade, children at the lowest quartile for vocabulary had approximately half the number of known words compared to students in the top quartile. Furthermore, according to the Matthew effect model proposed by Stanovich (1986Stanovich ( , 2000, those individual differences in vocabulary may even increase over time.…”

Lexical standards for expository writing at Grade 3:The transition from early literacy to academic literacy

“…A validation study of this reference corpus (Roessingh & Elgie, 2009) and the lexical profiling strategy that underlies the online tool confirms for us the utility of both this tool and the approach to language sample analysis it affords for the purposes of our research reported here. It appears that patterns in children's vocabulary development remain remarkably stable over time (Biemiller & Slonim, 2001), and although they may acquire different content words (tiddly winks has turned into warrior games) the general, high utility academic words that are characteristic of CALP-like discourse have not changed. Over time, we expect to see a shift in the shape of individual vocabulary profiles, reflecting increasing access to low frequency, and sophisticated words, including those that are counted as 'Off-list'.…”