1. A syntactic and semantic treatment of ergativity in a system network grammar Vincent Spincemaille

2. The Company • Language And Computing • Zonnegem, Belgium • 30 employees • Focus: medical market • Products: automatic text indexing, information retrieval, medical ontology • www.landc.be

3. The Linguistics Department • building a computational grammar for English to analyse medical abstracts/patient reports in order to improve information retrieval • Goal: text understanding (so a correct grammatical AND conceptual analysis) • Method: grammar formalism = Systemic-Functional Grammar (SFG) • My task description: adjust the grammar to include correct parsing of ergativity (plus conceptual representation); • -mental verbs • -aspectual verbs

4. The Grammar Formalism • System networks • design of the grammar: features, AND-gates, OR-gates, realizations intransitive-verb lexical-verb monotransitive-verb transitive-verb ditransitive-verb Compl: +1 Compl: {noun or {acc and pronoun}}

5. Dependency • dependency vs constituency

6. Linkbase • Concepts connected by Linktypes

7. Concept modeling in Linkbase • concepts, not lemma’s: • BIOPSY OF LIVER • IS-A: biopsy • HAS-SOURCE: liver • HAS-THEME: liver biopsy tissue • linguistic descriptions of processes: material processes, being processes, etc.

8. Has-HC-Phenom MEDIC CANCER MEDICAL-PROCEDURE Has-Actor Has-Actee PATIENT “The doctor that treated the patient now has Cancer”

9. Ergativity • examples: • (1a) The bookkeeper killed his wife. • (1b) *His wife killed. • (2a) The doctor opened the valve. • (2b) The valve opened. • How introduced into the grammar? • - list ergative verbs • - new category in lexicon: ergative verb • - new direct object: ErgObj

10. Ergativity(2) • difference with normal transitive verbs: • syntactically: limited • main difference: semantically: • characterization of ergativity in terms of different process-participant relations (Davidse 1999): • Transitive sentences: actor/goal • Ergative sentences: ergative-instigator/ergative medium

11. INVESTIGATION-PROCESS LINKBASE Actor Actee (goal) Transitive- verb syntax Object Subject examines The doctor the patient Ergativity (3)

12. IMPROVING-PROCESS HAS- ERGATIVE- MEDIUM HAS-ERGATIVE- INSTIGATOR LINKBASE Ergative- verb syntax ErgObj Subject improves The doctor the patient Ergativity (4)

13. IMPROVING-PROCESS HAS-ERGATIVE- MEDIUM LINKBASE Ergative- verb syntax Subject improved The patient Ergativity (5)

14. Conceptual definition of ergativity • transitive verbs: material process: • criteria list: • has-actor • has-actee • ergative verbs: ergative process: • criteria list: • has-instigator • has-medium

15. LINKBASE: ERGATIVE PROCESS SEMANTIC MAPPING (language-dependent) Het virus infecteert het weefsel Le docteur augmente la pression The doctor increased the pressure. Het weefsel infecteert. The pressure increased. La pression est augmentée.

16. Conclusion • Develop a system which handles ergativity in the grammar • System network grammar: wide coverage, transparent grammar • Practical use of theoretical linguistic research • Further development: develop a semantic mapping component, add probabilistic parsing to reduce number of parses