1. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab1 LG617 A brief introduction to XLE Kakia Chatsiou achats@essex.ac.uk Dept of Language and Linguistics University of Essex

2. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab2 Outline About XLE A closer look at XLE –Grammar architecture –Getting started –Inspecting a basic grammar.lfg file –XLE interface –XLE vs LFG notations Hands-on Session Where is XLE used? –ParGram Project –Powerset –XLE Web interface

3. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab3 About XLE XLE stands for Xerox Linguistics Environment Under current development at PARC (Palo Alto Research Center, USA) A computational environment developed to facilitate the writing and debugging of Lexical Functional Grammars C-structure, f-structure, s-structure, and further projections can be defined Implemented in C; works in Unix, Linux, MacOS. Integrates a morphological analyser employing Finite State Technology Can be used for both parsing and generation Includes tools for various grammar development activities (such as analysing performance, test-suites)

4. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab4 Other Finite State Tools Other Finite State Tools Tokenizer Morpholo- gical Analyser FST Morpholo- gical Analyser FST Lexicon(s) (Hand-written Or Automatically Extracted) Lexicon(s) (Hand-written Or Automatically Extracted) LFG Grammar (rules, templates) LFG Grammar (rules, templates) Grammar Resources (parsing and generating) Grammar Resources (parsing and generating) A closer look at XLE :: Basic Grammar Architecture ::

5. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab5 runs on the unix4 server can be accessed via a Secure Shell (SSH) ( Start>Network Services>Secure Shell ) We will use the emacs editor to edit the XLE grammar files (offers syntax colouring and an LFG toolbar for.lfg files) In the SSH command line, type emacs Open a grammar file ( Ctrl-x Ctrl-f or File>Open file ); they normally have an.lfg extension A closer look at XLE :: Getting Started ::

6. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab6 A closer look at XLE :: Inspecting a grammar file ::

7. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab7 A closer look at XLE :: Inspecting a grammar file :: Configura- tion Section

8. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab8 A closer look at XLE :: Inspecting a grammar file :: Rules Section

9. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab9 A closer look at XLE :: Inspecting a grammar file :: Lexicon Section

10. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab10 A closer look at XLE :: Inspecting a grammar file :: Grammar Version ID

11. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab11 A closer look at XLE :: Inspecting a grammar file :: Language ID

12. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab12 A closer look at XLE :: Inspecting a grammar file :: Component ID

13. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab13 A closer look at XLE :: Inspecting a grammar file :: XLE version ID

14. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab14 A closer look at XLE :: Inspecting a grammar file :: 4 dashes signal the end of each section/ file

15. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab15 A closer look at XLE :: Inspecting a grammar file :: The default category when parsing

16. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab16 A closer look at XLE :: Inspecting a grammar file :: specification of which lexical entries, and rule are given precedence (here precedence is given to the grammar with version ID STARTER and language ID LANGUAGE )

17. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab17 A closer look at XLE :: Inspecting a grammar file :: list of the grammatical relations which must be subcategori- sed for in order to appear in the argument list of the PRED

18. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab18 A closer look at XLE :: Inspecting a grammar file :: list of attributes whose values must contain a PRED

19. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab19 A closer look at XLE :: Inspecting a grammar file :: Phrasal category

20. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab20 A closer look at XLE :: Inspecting a grammar file :: Schema / f-structure information

21. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab21 A closer look at XLE :: Inspecting a grammar file :: 

22. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab22 A closer look at XLE :: Inspecting a grammar file :: 

23. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab23 A closer look at XLE :: Inspecting a grammar file :: Morpho- logical marker

24. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab24 % create-parser {demo-eng.lfg} % parse {Mary saw the boys with the telescope} parsing {Mary saw the boys with the telescope} 2 solutions, 0.01 CPU seconds, 23 subtrees unified A closer look at XLE :: XLE interface ::

25. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab25 A closer look at XLE :: XLE interface :: % parse {Mary saw the boys with the telescope} parsing {Mary saw the boys with the telescope} 2 solutions, 0.01 CPU seconds, 23 subtrees unified

26. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab26 A closer look at XLE :: XLE interface :: C- structure f- structure Packed representa- tion of f- structures Representa- tion of logical choices (in cases of ambiguity) % parse {Mary saw the boys with the telescope} parsing {Mary saw the boys with the telescope} 2 solutions, 0.01 CPU seconds, 23 subtrees unified

27. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab27 LFG notationXLE-equivalentDescription ↑ ^f-structure metavariable ↓ !f-structure metavariable ==defining equality ≡ =meta-category definition =c=c or =Cconstraining equality ∈ $set membership ¬~negation (complementation) ← <-off-path constraint → ->off-path constraint ⊑ <<subsumption (subsumes) ⊒ >>subsumption (is subsumed by) { a | b | c |... | z }{ a | b | c |... | z }disjunction ( a ){ a }optional f-structure constraint A closer look at XLE :: XLE vs LFG Notations ::

28. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab28 Hands-on Session

29. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab29 Outline About XLE A closer look at XLE –Grammar architecture –Getting started –Inspecting a basic grammar.lfg file –XLE interface –XLE vs LFG notations Hands-on Session Where is XLE used? –ParGram Project –Powerset –XLE Web interface

30. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab30 Where is XLE used? ParGram Project PowersetThe core technology used in the consumer search engine based on natural language processing which is currently under development by Powerset XLE web interface, a web-based tool for parsing LFG grammars using the XLE tool

31. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab31 Where is XLE used? :: ParGram Project :: Project Objectives Broad coverage grammars –Inclusion of important and frequently occurring constructions –Linguistically motivated analyses Parallel and crosslinguistic development of grammars between the participating members –All grammars are guided by a common set of linguistic principles and a commonly agreed upon set of grammatical analyses and features –Identical treatment of core crosslinguistic phenomena Methods in grammar engineering –Common test methods and evaluation strategies –Balance between efficiency, performance, reliability and maintainability across grammars

32. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab32 Participating Members PARC, CA Chinese, English, French Essex Greek, Welsh Manchester Arabic Oxford Malagasy DCU, Ireland Chinese, English, French, German, Japanese, Spanish Fuji XEROX Japanese Bergen, Norway Georgian, Norwegian, Tigrinya Ho Chi Minch Vietnamese Debrecen Hungarian IMS, Stuttgart German Konstanz Urdu Sabanci, Istanbul Turkish Where is XLE used? :: ParGram Project ::

33. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab33 Where is XLE used? :: Powerset Search Engine ::

34. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab34 About Powerset search engine a Microsoft-partner company, currently building a transformative consumer search engine based on natural language processing: –It is based on technologies that take advantage of the structure and nuances of natural language –It offers an innovative approach to searching: It breaks the confines of keyword search  queries using both keywords, short phrases and natural language Makes search more natural and intuitive Aims at fundamentally changing how we search the web and at the same time delivering higher quality results currently searching Wikipedia with the help of FreeBase as the semantic knowledge database –Its technology has recently made into the Microsoft Live Search Engine (source: http://www.powerset.com )http://www.powerset.com Where is XLE used? :: Powerset Search Engine ::

35. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab35 Example queries Who is Indiana Jones? Which are the films that Spielberg directed? I am looking for Van Gogh’s paintings Paintings by Van Gogh Albums by westlife Books by Charles Dickens Where is XLE used? :: Powerset Search Engine ::

36. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab36 a web-based tool for parsing LFG grammars using the XLE tool outputs c-structures, f-structures and mrs-structures. allows the user to choose a grammar and type in a sentence to be analyzed. The sentence is then processed by the XLE parser, and the resulting structures are displayed. has a facility for uploading (small) user grammars, mainly for teaching purposes. Where is XLE used? :: The XLE Web Interface ::

37. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab37 References / Sources ParGram http://www2.parc.com/isl/groups/nltt/pargram/ XLE Web Interface Documentation: http://maximos.aksis.uib.no/Aksis-wiki/XLE-Web http://maximos.aksis.uib.no/Aksis-wiki/XLE-Web XLE Documentation http://www2.parc.com/isl/groups/nltt/xle/doc/xle_toc.html Powerset http://www.powerset.com/

38. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab38 Thank you! Next week (March 5 th ) Dependency Constructions –Weak Crossover and Traceless UDCS: Dalrymple, Kaplan and King (Kakia) –Tough Contructions: Dalrymple and King (Budour) Papers still available: Morphology-Syntax Interface: Lexical sharing –Turkish Suspended Affixation: Broadwell –Preposition Determiner Contractions: Wescoat On Grammatical Functions –Polish Subjectless Constructions: Kibort –Nature of OBJ: Borjars and Vincent Functional and Lexical Verbs –English Auxiliaries: Falk (http://courses.essex.ac.uk/lg/lg617/sessions08.html)

39. Kakia Chatsiou A brief introduction to XLE 26.02.2009LG617 - XLE Lab39 Thank you! For more information and updates on the progress of the project visit http://privatewww.essex.ac.uk/~achats/projects/greekgram/index.html