VerbNet

1. VerbNet A Class-Based Verb Lexicon Presentation of Magdalena Leshtanska

2. VerbNet Martha Palmer http://verbs.colorado.edu/~mpalmer/projects/verbnet.html

3. Overview • VerbNet – basic idea • The Levin Verb Classification - overview, drawbacks, refinement • VerbNet Classes – LTAG • Examples • References

4. The Levin Verb Classification Beth Levin. 1993. English Verb Classes andAlternation, A Preliminary Investigation. TheUniversity ofChicago Press.

5. Example – break and cut • Transitive construction • John broke the window.John cut the bread. • Middleconstruction • Glassbreaks easily. This loaf cutseasily. • Simple intransitive construction • The window broke. *The bread cut. • cut describes actions directedat achieving the goal of separating an object into pieces. • break can‘t occur in the conative, cause it only specifies a resulting change of state – an object is separated into pieces If state is unchanged, no breaking actions are recognized.

6. The Levin Verb Classification Israelul a lovit o bază militară aeriană în nord-vestul Siriei Băsescu îşi mută privirea asupra copilului şi îl loveşte pe acesta cu dosul palmei peste faţă. O maşină a Ambasadei României la Sofia a lovit mortal un bulgar. Doi paparazzi, retinuti dupa ce au lovit doi cameramani langa localul nuntii lui Tariceanu. Bilantul furtunii “Christian” care a lovit vestul si nordul Europei. În prima repriză, portughezul a şutat puternic o minge spre lateral, iar balonul a lovit o fetiţă din tribune.

7. The Levin Verb Classification Mă gândesc să mănânc ceva. La ce se pot gândi 3 fete când găsesc un trandafir. Din punctul meu de vedere, m-aş gândi la o comisie specială. Adică nu poţi să te gândeşti la ce nu vrei să te gândeşti fără să te gândeşti la asta. Când vom termina procesul de restituire poate putem gândi un sistem de finanţare autonom pentru biserici. O carte din care înveţi să fii mereu cu un pas înainte, să gândeşti înainte de a vorbi, să negociezi. Caută să fii matur(ă) înainte de a te gândi la căsătorie. Poate se va gândi cineva şi la potenţialul cercetării ştiinţifice româneşti.

8. The Levin Verb Classification Approaches towards forming verb classes (Levin1993) Predict syntax, using semantic information I can buy a house vs *I can think a house Predict semantics, using syntactic information to hit someone vs to hit on someone Assumesthe sets of syntactic frames a verb can appear in reflect underlyingsemantic components that constrain allowablearguments Classes are based on the (in)ability of averb to occur in pairs of meaning preserving syntactic frames (diathesisalternations)

9. The Levin Verb Classification Что будет если в Колу кинуть Ментос. Какой из банков можно кинуть. Мужичок пытается кинуть банк на 24 млн, есть ли шанс? Вот команда и кидает ему мячи, а он закладывает их в корзину. не могу понять куда кидать конфиг. конфиг можно кидать куда угодно в пределах папки res_mods\xvm, но в файле res_mods\xvm\xvm.xc нужно указать на него. "Фратрия" призвала болельщиков не кидать файеры и не приводить на трибуну не болеющих за "Спартак" друзей. Как заставить Фарфокс молча кидать торрент-файлы в uTorrent? Кидать или не кидать туалетную бумагу в унитаз при локальной канализации.

10. The Levin Verb Classification - Drawbacks • Inconsistencies – verbs can exist in multiple lists, sometimes with conflicting structure • Levin explicitly states the syntax for each class, but fallsshort of assigning semantic components to each. And syntax alone is not enough: • John left the ball on the field (gave away) • John left the field (went out) • But: John left a fortune (gave away)

11. Levin Classes - Refinement (Dang 1998) • Intersective Levin classes • If more than 3 members from intersected classes overlap, they‘re moved to a subcalss of their own • Result: a fine-grained version, suitable for applications

12. VerbNet - overview • Largest online verb lexicon for English • Hierarchical structure of intersected Levin verb classes • LTAG formalism captures syntax for each verb class and assigns semantic predicates • Links to other lexical resources e.g. WordNet

13. VerbNet - overview Table 1: Summary of the Lexicon's Extension

14. VerbNet Classes • Hierarchically organized • Class members sharefeatures • a verb or subclass inherits features from the parent andmay add more information • Capture both syntax and semantics • Thematic roles - Agent, Theme,Location,.. • Syntactic frames. Each frame has • selectional restrictions for the arguments in it – e.g. the agent of „run“ should be animate • semantic predicates with a time function

15. VerbNet Classeshttp://verbs.colorado.edu/verb-index/vn/class-h.php

16. VerbNet Classes109 classes Putting Removing Sending and carrying Change of possession Hold and keep Throwing Contact by impact Combining and attaching Separating and disassembling Ingesting Sound made by animals Psychological state Killing Appearance and disappearance Aspect (start, stop) Relating and correlating Lingering and rushing Emission (sound, smell) . . . Creation and transformation Perception Social interaction Contact by impact Communication Body related Motion Measure Change of state

17. VerbNet Syntactic Frames • Come as an ordered sequence of thematic roles • John hit the ball- Agent V Patient • John hit at the window- Agent V at Patient • John hit the sticks together– Agent V Patient[+plural] together • Adorned with a conjunction ofsemantic predicates. • Semantic predicates can be • General (e.g.cause, motion) • Specific (e.g.,suffocate) • Variable (Prep) • Each predicateincludes a time function showing at whatstage in the event it holds: start, during, end, result

18. VerbNet Syntactic Framesexamplesbegin-55.1

19. VerbNet Syntactic Framesexamplescharacterize-29.2

20. VerbNet Syntactic Framesexampleseat-39.1-1

21. VerbNet Syntactic Framesexamplesentity_specific_modes_being-47.2

22. VerbNetThematic Roles23 roles

23. VerbNetSelectional  Restrictions: semantic classes exchange-13.6

24. VerbNetSelectional  Restrictions: semantic classes hurt-40.8.3

25. VerbNetSelectional  Restrictions: semantic classes wink-40.3.1

26. VerbNetSelectional  Restrictions: semantic classes

27. VerbNet Classes – LTAG Lexicalized Tree-Adjoining Grammar • Classes modelled by LTAG (Lexicalized Tree-Adjoining Grammar) • LTAG allows to • generate syntactic variants, e.g. passive from declarative • incorporate semantics into the model

28. LTAG - Run

29. LTAG - Hit

31. Members, Roles & Class Hierarchy

32. Syntactic Frames – Hit 18.1

33. …Semantic representation

34. References • Hoa Trang Dang, Karin Kipper, Martha Palmer and J. Rosenzweig. 1998 “Investigating Regular Sense Extensions Based on Intersective Levin Classes”. In Proceedings of Coling-ACL98. Montreal, CA. • Hoa Trang Dang, Karin Kipper, and Martha Palmer 2000. Integrating compositional semantics into a verb lexicon. In Proceedings of the Eighteenth International Conference on Computational Linguistics COLING- 000), Saarbrücken, Germany, July- August. • Karin Kipper, Hoa Trang Dang, andMartha Palmer.2000a. Class-basedconstruction of a verb lexicon.InProceedings of the Seventh NationalConference onArtificial Intelligence (AAAI-2000), Austin, TX, July-August. • Beth Levin. 1993. English Verb Classes andAlternation,A Preliminary Investigation. TheUniversity ofChicago Press.