Measuring maturity

Measuring maturity Richard Hudson Institute of Education, London July 2009

Plan • What is maturity as applied to writing? • How vocabulary correlates with maturity. • Why vocabulary correlates. • How syntax correlates with maturity. • Why syntax correlates. • Implications for teaching. • Implications for assessment.

Plan • What is maturity? • How vocabulary correlates with maturity. • Why vocabulary correlates. • How syntax correlates with maturity. • Why syntax correlates. • Implications for teaching. • Implications for assessment.

Non-linguistic maturity in writing • Age of writer • KS1 – KS4 • age 20 – 30 – 40 – 50 …. • Quality of writing • as judged by experienced examiners • National Curriculum Level • GCSE grade

Less linguistic maturity • He had just been in a horrible battle and he had killed lots of people. When he had finished his battle he was exhausted and he was tottering and came across a beautiful lady who was singing beautiful songs … • Sarah, Year 6 • NC Level 3

More linguistic maturity • Giles Harvey, a former Eton pupil was one and a half times over the limit when he was involved in a head on crash while he was racing his BMW sports car. • Joanne, Year 9 • NC Level 7

Non-linguistic and linguistic maturity • How do we know what’s‘mature’ in language? • Ask what linguistic features tend to be used: • only by older writers • only in more highly valued writing • This avoids circularity.

Measures of vocabulary • Lexical diversity (type/token ratio) • Sarah: 0.66 • Joanne: 0.84 (first 32 words) • Lexical sophistication (e.g. word length) • Lexical density (grammatical/lexical) • Errors (e.g. spelling) • Nouniness Nouniness?

Nouniness • What percentage of word tokens are nouns? • Noun = common or proper noun • Sarah: 15% • Joanne: 31% • Nouniness increases with maturity

Nouniness x maturity

Why is nouniness mature? • In 2007 I had no idea. • I now have some relevant data • thanks to Gwillim Law and Jasper Holmes • Conclusion: nouniness increases with maturity because … • Rarer words tend to be nouns. • So nouniness is part of sophistication

Rarer words tend to be nouns % of lemmas Nouns increase share with rarity frequency

Nouniness x task • Narrative tasks produce less nouny writing.

Is this the same as Nominality? • ‘Nominal’ style favours: • noun, adjective, preposition • favoured by adult ‘informational’ writing • ‘Verbal’ style favours: • verb, adverb, pronoun • favoured by adult ‘imaginative’ writing • Is nominal/verbal ratio relevant to children? • Sarah: 0.61, Joanne: 2.0

So what? • Mature writers use more rare words. • So they must have a wider vocabulary. • So their linguistic maturity can be measured in terms of: • word frequencies – how many rare words? • vocabulary diversity – type/token ratio.

Two kinds of syntactic measure • General • e.g. Sentence length or T-unit length • Specific • e.g. apposition • Giles Harvey, a former Eton pupil • (written by Joanne)

General measures • T-unit length • T-unit = words in a main clause, including all subordinate clauses • Coordination • shows immaturity • and: Sarah = 3, Joanne = 0 • Subordination • subordinate clauses: Sarah = 2, Joanne = 2

But subordination is mature (if you’re young) steady rise in KS1 and KS2 subordinate clauses per 100 words fall in best writers at KS3/4

Age and syntactic complexity

Specific syntax • apposition • ‘swapping places’ a little town called Sea Palling about three miles down the road was • preposition-initial relative clauses • the box I put it which in

Plan • What is maturity as applied to writing? • How vocabulary correlates with maturity. • Why vocabulary correlates. • How syntax correlates with maturity. • Why syntax correlates with maturity. • Implications for teaching. • Implications for assessment.

Why? General syntactic measures • These show increasingly complex syntax. • Two possible non-linguistic reasons: • increasingly complex ideas • increasingly powerful working memories. • Maybe complexity increases with age throughout life.

Why? Specific syntactic measures • These show increasingly diverse syntax. • One linguistic reason: growth of linguistic knowledge. • Assumption: we do not ‘know the grammar of our language by age 5’! • There’s a great deal of grammar to be learned at school.

Errors as signs of growth • … he seems a little excited by the encounter of aliens … • … he also described their difficulty to move … • …it was now that I was so disappointed I did not have a camera …[inappropriate] • The creature I estimate was surfaced at the most for one minute, of which all I had spent just staring at the creature, …

Plan • What is maturity as applied to writing? • How vocabulary correlates with maturity. • How syntax correlates with maturity. • Why vocabulary correlates. • Why syntax correlates. • Implications for teaching. • Implications for assessment.

How can teachers promote maturity? • Ignore general syntax • this depends on cognitive development • Focus on specifics: • vocabulary • specific syntax • Help learners to notice new patterns. • Teach new patterns explicitly.

Plan • What is maturity as applied to writing? • How vocabulary correlates with maturity. • How syntax correlates with maturity. • Why vocabulary correlates. • Why syntax correlates. • Implications for teaching. • Implications for assessment.

Assessment of writing • Why not use automated assessment? • at least as a supplement to humans • All these measures can be mechanised • if children use word processors. • Research question: • Is the agreement between two humans better than between a human and a machine?

Conclusion • Maturity of language can be defined • in relation to age and grading. • So it can be measured • in terms of identifiable linguistic features. • Specific linguistic features can be taught. • They can also be identified automatically.

Thank you • This presentation is available at www.phon.ucl.ac.uk/home/dick/talks.htm

Measuring maturity