1. From Question-Answering to Information-Seeking Dialogs Jerry R. Hobbs USC/ISI Marina del Rey, CA with Douglas Appelt, David Israel, Peter Jarvis, David Martin, Mark Stickel, and Richard Waldinger of SRI Chris Culy SRI International Menlo Park, CA

2. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs2 Decomposing Questions Could Mohammed Atta have met with an Iraqi official between 1998 and 2001? IE Engine Geographical Reasoning Question Decomposition via Logical Rules Resource Attached to Reasoning Process meet(a,b,t) & 1998  t  2001 at(a,x 1,t) & at(b,x 2,t) & near(x 1,x 2 ) & official(b,Iraq) go(a,x 1,t)go(b,x 2,t) IE Engine Temporal Reasoning Logical Form SNARK

3. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs3 The Problem Inference in large knowledge bases is required for competent question-answering Many rich but heterogeneous knowledge bases exist today How do we make use of them in a single system?

4. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs4 Outline Three Resources: 1.The Semantic Web: Teknowledge’s search engine ASCS 2.An Information Extraction Engine: SRI’s TextPro 3. An Ontology of Time: DAML-Time

5. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs5 DAML Search Engine pred: arg1: arg2:Indonesia ?x capitalnamespace Searches entire (soon to be exponentially growing) Semantic Web Also conjunctive queries: population of capital of Indonesia Problem: you have to know logic and RDF to use it. Tecknowledge has developed ASCS:

6. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs6 DAML Search Engine as AQUAINT Web Resource pred: arg1: arg2:Indonesia ?x capitalnamespace Searches entire (soon to be exponentially growing) Semantic Web Solution: You only have to know English to use it; Makes the entire Semantic Web accessible to AQUAINT users. Also: Can use it for subqueries. AQUAINT System capital(?x,Indonesia) procedural attachment in SNARK

7. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs7 Namespace Problem Where to find the right predicates? In QUARK: Subtheories linking predicates to namespaces Subtheories linking topics to namespaces In DAML/ASCS: EQUIVALENT statements Standardized ontologies Use WordNet and SUMO to expand query Any namespace Decreasing precision Decreasing precision

8. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs8 Information Extraction Engine as a Resource Document retrieval for pre-processing TextPro: Top of the line information extraction engine recognizes subject-verb-object, coref rels Analyze NL query w GEMINI and SNARK Bottom out in a pattern for TextPro to seek Keyword search on very large corpus TextPro runs over documents retrieved

9. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs9 Linking SNARK with TextPro TextSearch(EntType(?x), Terms(p), Terms(c), WSeq) & Analyze(WSeq, p(?x,c)) --> p(?x,c) Call to TextPro Type of questioned constituent Synonyms and hypernyms of word associated with p or c Answer: Ordered sequence of annotated strings of words Match pieces of annotated answer strings with pieces of query Subquery generated by SNARK during analysis of query

10. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs10 Three Modes of Operation for TextPro 1.Search for predefined patterns and relations (ACE-style) and translate relations into SNARK's logic Where does the CEO of IBM live? 2.Search for subject-verb-object relations in processed text that matches predicate-argument structure of SNARK's logical expression "Samuel Palmisano is CEO of IBM." 3.Search for passage with highest density of relevant words and entity of right type for answer "Samuel Palmisano.... CEO.... IBM." Use coreference links to get most informative answer ACE Role and AT Relations

11. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs11 First Mode TextSearch(Person, Terms(CEO), Terms(IBM), WSeq) & Analyze(WSeq, Role(?x,Management,IBM,CEO)) --> CEO(?x,IBM) CEO(Samuel Palmisano,IBM) Analyze Entity1: {Samuel Palmisano, Palmisano, head, he} Entity2: {IBM, International Business Machines, they} Relation: Role(Entity1,Entity2, Management,CEO) CEO

12. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs12 Three Modes of Operation for TextPro 1.Search for predefined patterns (MUC-style) and translate template into SNARK's logic Where does the CEO of IBM live? 2.Search for subject-verb-object relations in processed text that matches predicate-argument structure of SNARK's logical expression "Samuel Palmisano heads IBM." 3.Search for passage with highest density of relevant words and entity of right type for answer "Samuel Palmisano.... CEO.... IBM." Use coreference links to get most informative answer

13. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs13 Second Mode TextSearch(Person, Terms(CEO), Terms(IBM), WSeq) & Analyze(WSeq, CEO(?x,IBM)) --> CEO(?x,IBM) " Samuel Palmisano heads IBM " CEO(Samuel Palmisano,IBM) Analyze

14. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs14 Three Modes of Operation for TextPro 1.Search for predefined patterns (MUC-style) and translate template into SNARK's logic Where does the CEO of IBM live? 2.Search for subject-verb-object relations in processed text that matches predicate-argument structure of SNARK's logical expression "Samuel Palmisano is CEO of IBM." 3.Search for passage with highest density of relevant words and entity of right type for answer "Samuel Palmisano.... CEO.... IBM." Use coreference links to get most informative answer

15. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs15 Third Mode TextSearch(Person, Terms(CEO), Terms(IBM), WSeq) & Analyze(WSeq, CEO(?x,IBM)) --> CEO(?x,IBM) " He has recently been rumored to have been appointed Lou Gerstner's successor as CEO of the major computer maker nicknamed Big Blue " CEO(Samuel Palmisano,IBM) Analyze " Samuel Palmisano...." coref

16. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs16 Challenges for IE Cross-document identification of individuals Document 1: Osama bin Laden Document 2: bin Laden Document 3: Usama bin Laden Do entities with the same or similar names represent the same individual? Metonymy Text: Beijing approved the UN resolution on Iraq. Query involves “China”, not “Beijing”

17. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs17 Temporal Reasoning: Structure Topology of Time: start, end, before, between Measures of Duration: for an hour,... Clock and Calendar: 3:45pm, Wednesday, June 12 Temporal Aggregates: every other Wednesday Deictic Time: last year,...

18. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs18 Temporal Reasoning: Goals Develop temporal ontology (DAML) Reason about time in SNARK (AQUAINT, DAML) Link with Temporal Annotation Language TimeML (AQUAINT) Answer questions with temporal component (AQUAINT) Nearly complete In progress

19. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs19 Convergence DAML Annotation of Temporal Information on Web (DAML-Time) Annotation of Temporal Information in Text (TimeML) Most information on Web is in text The two annotation schemes should be intertranslatable

20. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs20 TimeML Annotation Scheme (An Abstract View) 2001 6 mos Sept 11 warning clock & calendar intervals & instants intervals inclusion before durations instantaneous events

21. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs21 TimeML Example The top commander of a Cambodian resistance force said Thursday he has sent a team to recover the remains of a British mine removal expert kidnapped and presumed killed by Khmer Rouge guerrillas two years ago. resist command sent recover Thursday saidnow remove kidnap 2 years presumed killed remain

22. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs22 Vision for Time Manual DAML temporal annotation of web resources Manual temporal annotation of large NL corpus Programs for automatic temporal annotation of NL text Automatic DAML temporal annotation of web resources

23. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs23 Spatial and Geographical Reasoning: Structure Topology of Space: Is Albania a part of Europe? Dimensionality: How long/big is Chile? Measures: How large is North Korea? Orientation and Shape: What direction is Monterey from SF? Latitude and Longitude: Alexandrian Digital Library Gazetteer Political Divisions: CIA World Fact Book,...

24. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs24 Spatial and Geographical Reasoning: Goals Develop spatial and geographical ontology (DAML) Reason about space and geography in SNARK (AQUAINT, DAML) Attach spatial and geographical resources (AQUAINT) Answer questions with spatial component (AQUAINT) Some capability now

25. 12/04/02Chris Culy, SRI, and Jerry Hobbs, USC/ISI, PIs25 Status and Future Directions Basic architecture essentially complete Good sampling of web and other resources have been incorporated Focus on bulking up knowledge base relevant to domain (nonproliferation) Focus on dialogue structure