corpus slide 1
TRANSCRIPT
What is a corpus?
The word corpus comes from Latin (“body”) and the plural is corpora
A corpus is a body of naturally occurring language …but rarely a random collection of text Corpora “are generally assembled with particular
purposes in mind, and are often assembled to be (informally speaking) representative of some language or text type.” (Leech 1992)
“A corpus is a collection of (1) machine-readable (2) authentic texts (including transcripts of spoken data) which is (3) sampled to be (4) representative of a particular language or language variety.” (MXT 2006: 5)
2
What is not a corpus?
A list of words is not a corpus Building blocks of language
A text archive is not a corpus A random collection of texts
A collection of citations is not a corpus A short quotation which contains a word or phrase that is the reason for
its selection A collection of quotations is not a corpus
A short selection from a text chosen on internal criteria by human beings A text is not a corpus
Intending to be read in different ways The Web is not a corpus
Its dimensions unknown, constantly changing, not designed from a linguistic perspective
Sinclair (2005)
3
What is a corpus for? A corpus is made for the study of language in a broad sense
To test existing linguistic theory and hypothesesTo generate and verify new linguistic hypothesesBeyond linguistics, to provide textual evidence
in text-based humanities and social sciences subjects
The purpose is reflected in a well-designed corpus
4
Why use corpora?
Even expert speakers have only a partial knowledge of a language A corpus can be more comprehensive and
balanced Even expert speakers tend to notice the
unusual and think of what is possible A corpus can show us what is common and
typical Even expert speakers cannot quantify
their knowledge of language A corpus can readily give us accurate
statistics
5
Why use corpora?
Even expert speakers are not always available to be consulted A corpus can be made permanently
accessible to all Even expert speakers cannot keep up
with language change A constantly updated corpus can reflect
even recent changes in the language Even expert speakers lack authority:
they can be challenged by other expert speakers A corpus can encompass the actual
language use of many expert speakers
LG3204 Corpus Linguistics 07-08 6
Benefits of corpus data Corpus data is more reliable
A corpus pools together linguistic intuitions of a range of language speakers, which offsets the potential biases in intuitions of individual speakers
Corpus data is more natural It is used in real communications instead of being invented
specifically for linguistic analysis Corpus data is contextualized
Attested language use which has already occurred in real linguistic context
Corpus data is quantitative Corpora can provide frequencies and statistics readily
Corpus data can find differences that intuitions alone cannot perceive E.g. synonyms totally, absolutely, utterly, completely,
entirely7
Corpora vs. intuitions Not necessarily antagonistic, but rather corroborate
each other and can be gainfully viewed as being complementary Armchair linguists and corpus linguists “need each other. Or
better, […] the two kinds of linguists, wherever possible, should exist in the same body.” (Fillmore 1992)
“Neither the corpus linguist of the 1950s, who rejected intuitions, nor the general linguist of the 1960s, who rejected corpus data, was able to achieve the interaction of data coverage and the insight that characterize the many successful corpus analyses of recent years.” (Leech 1991)
The key to using corpus data is to find the balance between the use of corpus data and the use of one’s intuitions
8
The corpus methodology
It is debatable whether CL is a methodology or a branch of linguistics CL goes well beyond this methodological role and has
become an independent discipline In spite of the name, CL is indeed a methodology
rather than an independent branch of linguistics in the same sense as phonetics, syntax, semantics or pragmatics These latter areas of linguistics describe, or explain,
a certain aspect of language use Corpus linguistics, in contrast, is not restricted to a
particular aspect of language - it can be employed to explore almost any area of linguistic research
9
A brief history of CL
The term corpus linguistics first appeared only in the early 1980s, but corpus-based language study has a substantial history
The history of CL can be split into two periods: before and after Chomsky
10
A brief history of CL
Before Chomsky Field linguists and linguists of the structuralist
tradition used “shoebox corpora” – shoeboxes filled with paper slips
Their methodology was essentially “corpus-based” in the sense that it was empirical and based on observed data
The work of early corpus linguistics was underpinned by two fundamental, yet flawed assumptions
The sentences of a natural language are finite. The sentences of a natural language can be collected and
enumerated. Most linguists saw the “corpus” as the only source of
linguistic evidence in the formation of linguistic theories
11
A brief history of CL
Chomsky revolution: Between 1957 and 1965 Chomsky changed the direction of linguistics from empiricism towards rationalism “Any natural corpus will be skewed. Some sentences
won’t occur because they are obvious, others because they are false, still others because they are impolite. The corpus, if natural, will be so wildly skewed that the description would be no more than a mere list.” (Chomsky 1962)
Our internal knowledge of language in human brain (competence, I-language) replaces observed data (performance, E-language)
Intuitions started to be relied on as evidence [Xiao, R. (2008) “Theory-driven corpus research: using
corpora to inform aspect theory”. In A. Lüdeling & M. Kyto (eds.) Corpus Linguistics: An International Handbook. Berlin: Mouton de Gruyter]
12
A brief history of CL Revival of CL
Corpus research was continued in a few centres (Brown, Lancaster) in the 60s-70s
The Brown University Standard Corpus of Present-day American English (Brown corpus)
Lancaster-Oslo-Bergen Corpus of BrE (LOB) The hardware still imposed some restrictions until the real
development started in the 1980s The marriage of corpora with computer technology rekindled
interest in the corpus methodology Since then, the number and size of corpora and corpus-based
studies have increased dramatically Nowadays, the corpus methodology enjoys widespread
popularity, and has opened up or foregrounded many new areas of research
13
Areas that have used corpora
Lexicography Lexical studies Grammatical studies Register/genre
analysis Language variation Contrastive analysis Translation studies Language change Language teaching
Semantics Pragmatics Stylistics Literary study Sociolinguistics Discourse analysis Forensic linguistics Computational linguistics …
14
Nature of corpus-based approach It is empirical, analysing the actual
patterns of use from natural texts It utilises a large and principled
collection of natural texts as the basis for analysis
It makes extensive use of computers for analysis, using both automatic and interactive techniques
It integrates both quantitative and qualitative analytical techniques
(Biber et al 1998: 4-5)
15
Why use computers?
Development of computer technology has revived CL
Machine-readability is a de facto attribute of modern corpora
Electronic corpora have advantages unavailable to their “shoebox” ancestors It is the use of computerized corpora, together
with computer programs which facilitate linguistic analysis, that distinguishes modern electronic corpora from early ‘drawer-cum-slip’ corpora
16
Why use computers?
Computerized corpora can be processed and manipulated rapidly at minimal cost E.g. searching, selecting, sorting and formatting
Computers can process machine-readable data accurately and consistently
Computers can avoid human bias in an analysis, thus making the result more reliable
Machine-readability allows further automatic processing to be performed on the corpus so that corpus texts can be enriched with various metadata and linguistic analyses Corpus markup and corpus annotation
17
A question for Deep Thought“Alright,” said the computer Deep Thought. “The Answer to the Great
Question...”
“Yes...!”
“Of Life, the Universe and Everything ...” said Deep Thought.
“Yes...!”
“Is...”
“Yes...!!!...?”
“Forty-two,” said Deep Thought, with infinite majesty and calm.
It was a long time before anyone spoke.
“Forty-two!” yelled someone in the audience. “Is that all you’ve got to show for seven and a half million years’ work?”
“I checked it very thoroughly,” said the computer, “and that quite definitely is the answer. I think the problem, to be quite honest with you, is that you’ve never actually known what the question is.”
Hitchhikers Guide to the Galaxy by Douglas Adams
What can we learn from this story?18
What corpora cannot do
Corpora do not provide negative evidence Cannot tell us what is possible or not possible Can show what is central and typical in language
Corpora can yield findings but rarely provide explanations for what is observed Interfacing other methodologies
The use of corpora as a methodology also defines the boundaries of any given study Importance of amenable research questions
The findings based on a particular corpus only tell us what is true in that corpus Generalisation vs. representativeness
See Unit B2 for pros and cons of corpora19
Ask corpora the right questions
Corpus linguistics as a methodology is only one of the (many) ways of doing things – “doing linguistics”
The usefulness of corpora depends upon the research question being investigated “They are invaluable for doing what they do, and what they do
not do must be done in another way.” (Hunston 2002: 20) The development of the corpus-based approach as a
tool in language studies has been compared to the invention of telescopes in astronomy If it is ridiculous to criticize a telescope for not being a
microscope, it is equally pointless to criticize the corpus-based approach for not doing what it is not intended to do
It is up to you to formulate research questions amenable to corpus-based investigation and to decide how to combine corpora with other resources
20
Testing your intuitions with BUY-BNC
http://corpus.byu.edu/bnc/
21
Most common noun in English
22
Search for [n*]
Top 10: time, people, way, years, year, work, government, day, man, world
Most common noun in adverts
23
Search for [nn*] in w-advert
Top 20: hotel, centre, time, world, holiday, day, service, year, house, facilities, range, club, bar, years, information, rooms, people, city, life, castle
Top 10 adj. in nonfiction vs. fiction
24
Top 10 in Nonfiction: aggregate, regulatory, offline, Keynesian, non-executive, macroeconomic, no-arbitrage, nationalised, short-run, pioneering
Top 10 in Fiction: Sabine, narrowed, unsmiling, flushed, clammy, navy-blue, sidelong, muttered, strangled, froggy
Distribution of phrasal verbs
25
“Talk” as a noun/verb in different registers
26
Synonyms: utter vs. sheer
27
Semantic prosody of caused
LG3204 Corpus Linguistics 07-08 28
Noun collocates of “CAUSE”:problems, damage, death, trouble, harm, concern, injury, problem, difficulties, loss, confusion, pain
data singular or plural?
29
Per million words:Singular: 776Academic: 21misc: 9.2spoken: 1.9newspaper: 1.6fiction: 0.3
Per million words:Plural: 1,035academic: 42.5misc: 8.8spoken: 0.2fiction/news: 0.1
How are women and men described?
30
reason for vs. reason to
31
Extra Practice with BNC VIEW
1) What are the top 5 modal verbs in English?
2) Is there any difference between verbs destroy, ruin, and demolish? If so, what is it?
3) Do you think the adjectives in “utterly + adjective” have anything in common? If so what is that?
4) Can we use the plural form of research as in “his researches”?
LG3204 Corpus Linguistics 07-08 32
Where to find what… BNCweb
http://bncweb.lancs.ac.uk/bncwebSignup/user/login.php BYU corpus hub: http://corpus.byu.edu/corpora.asp CQP corpus hub at BFSU (ID/pass=test):
http://124.193.83.252/cqp/ Bank of English (56M sample)
http://www.collins.co.uk/Corpus/CorpusSearch.aspx Sketch Engine: http://www.sketchengine.co.uk/ David Lee’s CL bookmarks
http://www.uow.edu.au/~dlee/CBLLinks.htm Corpus linguistics, translation, and language learning
http://sites.google.com/site/federicozanettinnet/cl-htm Corpus4u Community: www.corpus4u.org
LG3204 Corpus Linguistics 07-08 33