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Measuring maturity

Richard Hudson

Institute of Education, London

July 2009

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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.

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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.

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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

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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

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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

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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.

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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.

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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?

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Nouniness

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

• Nouniness increases with maturity

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Nouniness x maturity

02468

1012141618

1 2b 3 4/F 5 6 7/C 8 A

grade

% n

ou

n KS1

KS2

KS3

KS4

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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.

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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

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Rarer words tend to be nouns

0

10

20

30

40

50

60

256

512

1024

2048

4096

8192

16384

32768

65536

111821

Noun

Verb

Adjective

Preposition

Adverb

% of lemmas

frequency

Nouns increase share with rarity

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Nouniness x task

• Narrative tasks produce less nouny writing.

02468

1012141618

KS1 KS2 KS3 KS4

non-narrative

narrative

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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

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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.

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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.

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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)

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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

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But subordination is mature

0

1

2

3

4

5

1 2b 3 4/F 5 6 7/C 8 A

grade

KS1

KS2

KS3

KS4

steady rise in KS1 and KS2

fall in best writers at KS3/4

(if you’re young)

subordinate clauses per 100 words

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Specific syntax

• apposition• ‘swapping places’

about three miles down the road

a little town called Sea Palling

was

• preposition-initial relative clauses

• the box I put it inwhich

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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.

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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.

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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.

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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, …

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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.

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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.

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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.

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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?

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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.

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Thank you

• This presentation is available at

www.phon.ucl.ac.uk/home/dick/talks.htm