Do we need lexicographers? Prospects for automatic lexicography Adam Kilgarriff Lexical Computing Ltd University of Leeds UK

Bolzano, May 2012Adam Kilgarriff 2 Outline  Precision and recall  Between corpus and dictionary  Shopping list  Conclusions

Bolzano, May 2012Adam Kilgarriff 3 Find me all the fat cats  a request for information

Bolzano, May 2012Adam Kilgarriff 4 High recall  Lots of responses  Maybe not all good

Bolzano, May 2012Adam Kilgarriff 5 High precision  Fewer hits  Higher confidence

Bolzano, May 2012Adam Kilgarriff 6 Information-seeking RecallPrecision Computers good bad People bad good

Bolzano, May 2012Adam Kilgarriff 7 Cyborg: part-human, part-computer Treat your computer with respect. You and it can do great things together.

Bolzano, May 2012Adam Kilgarriff 8 Lexicography: finding facts about words Shopping list  collocations  grammatical patterns  examples  synonyms  labels –region –domain –register  translations  meanings

Szeged, Jan 2008Kilgarriff, Global WordNet 9 What is a word sense (1)  SFIP –Sufficiently frequent insufficiently predictable  (a glass of) whisky  x (a glass of) tequila

Szeged, Jan 2008Kilgarriff, Global WordNet 10 What is a word sense (2) homonymy analogy polysemy rules collocation

Szeged, Jan 2008Kilgarriff, Global WordNet 11 What is a word sense (3)  A cluster –Of instances of use  Operationalised as: corpus lines –Clustered by lexicographers

Szeged, Jan 2008Kilgarriff, Global WordNet 12 What is a word sense (3)

Szeged, Jan 2008Kilgarriff, Global WordNet 13 What is a word sense (3)

Szeged, Jan 2008Kilgarriff, Global WordNet 14 What is a word sense (3)

Szeged, Jan 2008Kilgarriff, Global WordNet 15 What is a word sense (3)

Szeged, Jan 2008Kilgarriff, Global WordNet 16 What is a word sense (3)  A cluster –Of instances of use  Operationalised as: corpus lines –Clustered by lexicographers  Makes sense of –Overlapping senses –Different dictionaries, different senses –Lumping and splitting

Szeged, Jan 2008Kilgarriff, Global WordNet 17 I don’t believe in word senses  Believe in: –resurrection ghost witch vampire god miracle fairy  Philosophy: –Ontological commitment –(same meaning different register)  “good entities to build belief systems on”

Szeged, Jan 2008Kilgarriff, Global WordNet 18 But I’m an NLP person  Automatic clustering?  Inspiration: –Hindle 1991, Schütze 1993, Grefenstette 1993, Lin 1999 –You can get semantic sense from corpora+stats

Szeged, Jan 2008Kilgarriff, Global WordNet 19 First attempt  Longman 1994  Abject failure –No grammar –Corpus too small and noisy –Naïve clustering –Useless programmer

Szeged, Jan 2008Kilgarriff, Global WordNet 20 Second attempt  SENSEVALS 1998, 2001, 2004…  mitigated failure –Rarely over two thirds correct

Szeged, Jan 2008Kilgarriff, Global WordNet 21 Third attempt  SADD (semi-automatic dictionary drafting) 2008  With Pavel Rychly  I thought I knew what I was doing but –Probably a failure

Szeged, Jan 2008Kilgarriff, Global WordNet 22 Collocations  Easy –Most words don’t go with most other words  Then build on what we can do well  (metaphor, analogy, homonymy, rules: all much harder)

Bolzano, May 2012Adam Kilgarriff 23 Lexicography: finding facts about words Shopping list  collocations  grammatical patterns  examples  synonyms  labels –region –domain –register  translations  meanings Yes ? No

Bolzano, May 2012Adam Kilgarriff 24 Thank you