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Patterns of usage A window to language cognition Galit W. Sassoon Bar Ilan University, Ramat Gan

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Patterns of usage – A window to language cognition

Galit W. Sassoon

Bar Ilan University, Ramat Gan

Patterns of usage – A window to language cognition

1. Introduction (8)

2. ‘Small’ balanced & annotated corpora (15)

3. The magic of large corpora (7)

1. Introduction

Studying patterns of usage

• Corpus linguistics concerns with the usage patterns as revealed in corpora: collections of naturally occurring uses of language, written texts and/or transcriptions of recorded speech.

• Chomsky's distinction between competence and performance

• Competence: Universal Grammar – A set of rules and parameters which generates an infinite number of

sentences: Those and only those we judge acceptable.

– UG is autonomous: independent of external—conceptual, cognitive, communicative, or social—factors.

• Performance: Language use, language behavior.

• So why study corpora??

Studying patterns of usage

• Provides a (relatively) objective view of language

• Reveals issues not accessible through introspection

• Can address almost any language aspect (syntax, semantic, pragmatics, psycholinguistics, sociolinguistics …)

• Very specific agendas: – male versus female usage of tag questions

– children's acquisition of irregular past participles

– counterfactual statement error patterns of Japanese students.

• Reveals contextual factors influencing variability in language use. – contextual preferences/ distribution of synonyms like begin/start or big/large/great.

– Adverbs/ aspectual verb forms in speaking/writing, newspapers/fiction

– To give Mary the book / the book to Mary

• Example:

Most vs. More than half (Solt 2014)

Studying patterns of usage • Diachronic development: Corpora from different times.

Has the frequency of a particular word/construction/meaning increased/decreased over time?

• Sociolinguistics: Corpora from different populations/genres.

Does usage vary by gender/ age/ social identity/ dialect/ register (= a variety of language used for a particular type of situations)

– fiction, academic prose, newspapers, blogs, casual phone conversations, …

– sub-registers within academic prose: scientific texts, literary criticism, ...

Language often behaves differently according to the register/speaker type, each with some unique patterns and rules.

• Acquisition: Child speech; child oriented speech.

• Aphasia: Language usage after brain damage

• …

Balanced vs. Large corpora • http://en.wikipedia.org/wiki/Corpus_linguistics:

– The LOB Corpus (1960s British English),

– Kolhapur (Indian English), Wellington (New Zealand English),

– Australian Corpus of English (Australian English),

– The Frown Corpus (early 1990s American English),

– The FLOB Corpus (1990s British English),

– International Corpus of English,

– British National Corpus (a 100 million word collection of a range of spoken and written texts, created in the 1990s by a consortium of publishers, universities Oxford and Lancaster),

– The British Library

– The American National Corpus

– Corpus of Contemporary American English (1990–present; 400+ million words; now available through a web interface).

– Wordnet: A large dictionary encoding synonym, antonym and subtype relations between words.

– The wordsketch engine: Collocates of words counted separately for each semantic-syntactic relation.

– Google e-books; All the books ever written

– The web

The corpus has to fit your purpose / research question

Annotation: Information added to the corpus

• Lemmatizing and POS tagging (annotating):

• Works work(V, SG, 3rdP, present),

• worked work(V, past)

• Lemmatizing is important if we are to extract

subcategorization frames of a verb considering

all its forms together, that is, searching by its

lemma.

Methods for annotation (classification by syntactic/ semantic category; as errors, …)

• Automatic classification (typically, in large corpora):

Some software programs searches corpora and lists the results.

You can program a software to classify data according to your criteria.

• Manual classification (in small corpora):

Especially useful for semantics & pragmatics, where automatic tools produce more noise than results.

• Classification using participants

Ask speakers for their judgment and follow the statistics.

Any level of linguistic information can be annotated

• The Andersen-Forbes database of the Hebrew Bible, is developed since the 1970s, in which every clause is represented with up to 7 levels of syntax, and every segment tagged with 7 information fields.

• The Quranic Arabic Corpus is annotated with multiple layers including morphological segmentation, part-of-speech tagging, and syntactic analysis (using dependency grammar).

-Andersen, Francis I.; Forbes, A. Dean (2003), "Hebrew Grammar Visualized: I. Syntax", Ancient Near Eastern Studies 40: 43–61 .

-Dukes, K., Atwell, E. and Habash, N. 'Supervised Collaboration for Syntactic Annotation of Quranic Arabic'. Language Resources and Evaluation Journal. 2011..

• The card corpus (Potts 2011?): Pragmatic annotation.

• Stanley Dubinsky and Paul Reed: Double Modal auxiliary verb distribution in various dialects of southern American English (1753 tokens).

• We need to know the frequency of each modal separately to make sense of this table!

Results: Frequencies – out of what?

First\Second Can Could Might Oughta Should Will Would

Can 0 0 2 0 0 0 1 3

Could 0 0 5 0 0 0 0 5

May 84 46 3 5 21 10 15 186

Might 171 883 1 74 60 15 148 1360

Ought to 0 2 0 0 0 1 1 4

Shall 0 0 0 0 0 0 0 0

Should 1 0 0 18 0 0 0 19

Useta 0 131 1 0 0 0 39 171 Will 4 0 1 0 0 0 0 5

Would 0 2 6 0 0 0 0 8

260 1064 19 97 81 26 204

2. A ‘small’ balanced corpus

• The Corpus of Contemporary American English (COCA; Mark Davies, Brigham

Young University) is the largest freely-available corpus of English, and the

only large and balanced corpus of American English.

• COCA is used by tens of thousands of users every month (linguists, teachers,

translators, and other researchers).

• COCA is also related to other large corpora.

• more than 450 million words of text

• equally divided to spoken, fiction, popular magazines, newspapers, and

academic texts.

• 20 million words each year from 1990-2012, updated regularly.

http://corpus.byu.edu/coca/

Searching COCA

Searching COCA

[j*] eyes to find two word strings composed of eyes preceded by an adjective.

[beat].[v*] to find just the verbal uses of beat.

[=clever] to find synonyms (intelligent, wise,…)

• Interface allows you to search for exact words/phrases, lemmas, part of speech,

surrounding words (collocates; e.g. all nouns somewhere near faint, all

adjectives near woman, …), synonyms.

• You can limit searches by frequency, or compare frequencies by genre, sub-

genres (or domain: movie scripts, sports magazines, …) or time (different years

1990-present).

COCA (Davies 1999-present) Chrat & KeyWordInContext

COCA (Davies 1999-present) Different registers

-Coca searches ‘un-’ and ‘non-’

in spoken vs. academic genres

-Similarly for adverbs: ‘a bit’, ‘a

little’ vs. ‘slightly’, ‘somewhat’

COCA (Davies 1999-present) Sociology; Sociolinguistics

Corpora of dialogues/ conversations:

-Turn taking

-Who speaks longer

-Who interrupts, who waits politely to her turn

-Who uses which speech acts (commands, requests, statements, questions)

Corpus usage in education: Second language teaching

Corpus usage in education: Second language teaching

Theoretical / Psycho Corpus linguistics Subtle distinctions revealed in language

behavior

-which adjectives does each modifier modifies more frequently?

-which other collocates do they have?

-in which speech acts or speech situations or regiters are they used?

-tendency to select deverbal adjectives derived from cause- vs. experiencer-

verbs? (slightly burnt/bent vs. a little needed; admired)

Acquisition & Atypical speech

http://childes.psy.cmu.edu MacWhinney, B. (2000). The CHILDES Project: Tools for analyzing talk. Third

Edition. Mahwah, NJ: Lawrence Erlbaum Associates.

The biggest collection of data on child language & tools for its research

• Transcripts, audio, and video materials In over 20 languages;

• 130 different corpora, all of which are publicly available.

• Spontaneous speech, narratives

• Part of the larger corpus TalkBank, which includes data from: • Aphasia

• Dementia

• SLI

• Second language acquisition

• Conversation analysis

• Classroom language learning.

The availability of corpora and tools to search them changed the theoretical view of many:

Revealed high overlap between child and caregiver production

suggestive of learning of concrete items as opposed to setting abstract parameters. Abstract categories only occur later

• Parisse & Le Normand (2000) studied the lexical overlap between child and adult language.

• More specifically, they compared 33 hours of speech produced by Philippe and the adults he is talking to (data taken from the Léveillé database in CHILDES).

• “72% of the bi-words [i.e. two consecutive words] produced by Philippe at 2;1 (in type, and 82% in tokens) correspond exactly to adult bi-words”

The availability of corpora and tools to search them changed the theoretical view of many:

• The Léveillé database in CHILDES

Limitations

• Linguistic analyses that use the methods and tools of corpus linguistics do not represent the entire language.

• Low frequency words/ constructions reveal interesting patterns of use, but you need to work harder to find data.

Deb Roy’s child’s lexicon’s development

http://www.ted.com/talks/deb_roy_the_birth

_of_a_word#t-363391

The birth of a word

2. The Magic of Large corpora

Studying patterns of usage • Large corpora:

Consist of millions or even billions of words.

• Computational corpus linguistics

– Use of computers to determine what rules govern language use.

– Various software programs and analytical tools allow the researchers to analyze a large number of parameters simultaneously and very fast.

– Practical applications: NLP ( enabling computers to interact with humans verbally), Machine translation ( the use of software to translate text or speech from one NL to another.); sense disambiguation; question answering help programs; speaking cellphones, robots; …

The web is the largest corpus • Problems:

– Non native speech

– Dependency on search engines such as Google which choose examples in non random ways.

– Repeated examples

– Non reliable estimations of counts of examples

– You don’t know who the speaker is (gender, age, languages, …)

– No annotations [except natural ones]

– …

• Advantages: – The web is big in size

– Web frequencies and judgments (Lapata & Keller 2003):

• Adj + N combinations extracted from the BNC vs. the web (using

google and altavista) were each compared to plausibility evaluations.

• Higher correlations of plausibility judgments with web searches than

BNC searches (between 0.6 to 0.7, vs. 0.5 coefficients)

Searching the internet Hebrew:

1. Ktiv male/xaser ( גבה, גבוה )

2. Problem with similarly written words (tall/eyebrow)

3. The problem of non native speakers is perhaps less pronounced

(e.g., fewer Chinese speakers that learn Hebrew as a second

language, as compared to English).

“Was it good? It was provocative.” Learning the meaning of scalar adjectives

Marie-Catherine de Marnee, Christopher D. Manning and Christopher Potts

The distribution of some

scalar modifiers across the

ten rating categories.

Natural annotation

38

THANK YOU! Comments are most welcomed

[email protected]