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Corpus analysis (2). Corpus Linguistics Richard Xiao [email protected] Outline of the session. Lecture Keyword Reference corpus Key keyword Practical WST keyword AntConc keyword Wmatrix keyword / key concept Extra: keyword analysis with CQPweb. What is a keyword?.

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Corpus analysis 2

Corpus analysis (2)

Corpus Linguistics

Richard Xiao

[email protected]


Outline of the session
Outline of the session

  • Lecture

    • Keyword

    • Reference corpus

    • Key keyword

  • Practical

    • WST keyword

    • AntConc keyword

    • Wmatrix keyword / key concept

    • Extra: keyword analysis with CQPweb


What is a keyword
What is a keyword?

  • Keywords are those words whose frequency is exceptionally high (positive keywords) or low (negative keywords) in comparison with a reference corpus

    • Keywords usually refer to positive keywords

    • But negative keywords are equally interesting (see Xiao and McEnery 2005)

      • They appear at the very end of your listing, in a different colour in WordSmith

      • They are omitted automatically from a keywords database for key keyword analysis and a keyword plot


Why keyword analysis
Why keyword analysis?

  • Indicating the ‘aboutness’ (Scott 1999) of a particular text or corpus

    • Contents analysis, discourse analysis

  • Also revealing the salient features which are functionally related to a particular genre (Xiao and McEnery 2005)

    • Genre analysis, stylistic analysis


How to do keyword analysis
How to do keyword analysis

  • Make a wordlist of the target corpus

  • Locate or make a word list of a reference corpus

    • Scott (2005) “In search of a bad reference corpus”

      • http://www.methodsnetwork.ac.uk/redist/pdf/es1_05scott.pdf

    • The reference corpus is usually larger than the target corpus

    • The appropriateness of a reference corpus depends on your research questions!

  • Compare the frequency of each item in the two wordlists to extract keywords – done automatically

  • Analyse and interpret keywords – you will do it!


Keywords in the party speeches
Keywords in the party speeches

  • Target corpus – just one text

    • David Cameron's speech at the Conservative conference (10 October 2012, Manchester)

      • http://www.bbc.co.uk/news/uk-politics-15189614

      • Local copy available (David_speech Unicode text) - download and unzip the file into a file folder:

        www.fass.lancs.ac.uk/projects/corpus/data/workshop3texts.zip

  • Reference corpus

    • The 100-million-word BNC: download and unzip (local copy available)

      www.lexically.net/downloads/version4/BNC_World.zip

  • Tool

    • WST Keyword




Keyword extraction in progress
Keyword extraction in progress

Warning: It can take time if you have loaded two large wordlists


Keywords in david s speech
Keywords in David’s speech

What do these

keywords tell us?

Negative keyword





Key clusters
Key clusters

Similar to word clusters,

but only keywords are used.


Key keywords
Key keywords

  • A key keyword is one which is "key" in more than one of a number of related texts

    • The more texts it is "key" in, the more "key key" it is

    • Can avoid extracting keywords which are unusually frequent in only a small number of files

  • Can be created automatically and as simple to extract as you do for keywords

  • n.b. Negative keywords are omitted automatically from a key keyword list


Making a batch wordlist
Making a batch wordlist

Specify a folder where you can write



Batch making keyword lists1
Batch making keyword lists

Specify a folder where you can write



Key keywords1
Key keywords

An "associate" is a keyword that appears in the same text

key coverage of the corpus


Keyword in antconc
Keyword in AntConc

target corpus

reference corpus


Keyword in antconc1
Keyword in AntConc

Key words in David's speech (in relation to Ed's speech)


Wmatrix keywords and key concepts
Wmatrix: Keywords and key concepts

  • POS and semantic tagging

  • Keyword / key concept analysis in Cameron’s speech in comparison with Miliband’s speech

  • Copy and paste the speeches into two separate text files

    • http://www.bbc.co.uk/news/uk-politics-15189614

    • http://www.labour.org.uk/ed-milibands-speech-to-labour-party-conference

  • Save the two texts as David_speech.txt and Ed_speech.txt

    www.fass.lancs.ac.uk/projects/corpus/data/workshop3texts.zip


Wmatrix keywords and key concepts1
Wmatrix: Keywords and key concepts

  • Login with your account using zhejiangxx account

    • http://ucrel.lancs.ac.uk/wmatrix3.html







My folders
“My folders”

Upload and tag Ed’s speech

…and click on “My folders”

Warning: Your folder view may look different!



Keyword list to download
Keyword list to download! compared to” dropdown box


Keyword cloud even more interesting
Keyword cloud – compared to” dropdown boxeven more interesting!


David s key concepts key concepts compared to
David’s key concepts compared to” dropdown box(“Key concepts compared to”)


Keyword analysis in online corpora
Keyword analysis in online corpora compared to” dropdown box

  • Using Lancaster’s CQPweb to compare British English (LOB+FLOB) and American English (Brown + Frown)

  • Login CQPweb

    • http://cqpweb.lancs.ac.uk

  • Similar analysis can be done at BSFU’s CQPweb corpus hub (different corpora)

    • http://124.193.83.252/cqp/

    • Account: ID=pass=test


Creating subcorpora
Creating subcorpora compared to” dropdown box


Creating subcorpus bre
Creating subcorpus BrE compared to” dropdown box


Creating subcorpus ame
Creating subcorpus AmE compared to” dropdown box


Making wordlists
Making wordlists compared to” dropdown box


Wordlist available now
Wordlist available now compared to” dropdown box


Computing keywords
Computing keywords compared to” dropdown box

You can make adjustments to the statistical measure, cut-off point, and minimum frequency according your research purposes.


Keywords in bre and ame
Keywords in BrE and AmE compared to” dropdown box


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