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Natural Language Querying of the Semantic Web. SRI International Information Science Institute. Beyond Single Question Single Source Answers. Most question answering systems to date have been limited to querying a single kind of source, a corpus of texts, for answers to a given question.
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Natural Language Queryingof theSemantic Web SRI International Information Science Institute AQUAINT 18 Month Meeting San Diego CA
Beyond Single QuestionSingle Source Answers • Most question answering systems to date have been limited to querying a single kind of source, a corpus of texts, for answers to a given question. • Most have been limited to answering single questions with single factual answers. • Aim: to move beyond these limits • Use of multiple (semi-)structured sources • Information-gathering dialogues AQUAINT 18 Month Meeting San Diego CA
QUARK • Natural language front end • Gemini: Unification Grammar (CFG backbone) • Mediated by powerful reasoning tool • SNARK: Full FO Theorem Prover • Powerful resource description and access capabilities • OAA: Intelligent delegation-based middleware • Visualization capabilities • TerraVision: Terrain Viewer AQUAINT 18 Month Meeting San Diego CA
Multiple Sources • Access to multiple knowledge sources • ADL Gazetteer • CIA World Factbook • NASA data sources • TextPro IE engine AQUAINT 18 Month Meeting San Diego CA
Goal: To Integrate DAML Search into QUARK • Agent Semantic Communications Service (ASCS) • Developed by Teknowledge. • Searches the Web for DAML pages. • Provides GUI for search. • Provides inference capability aimed at broadening and relaxation of queries. AQUAINT 18 Month Meeting San Diego CA
The ASCS Search Page AQUAINT 18 Month Meeting San Diego CA
ASCS: A Use Case To find the capital of Syria, a user must input pred: capital Searches entire Semantic Web capital(?x,Syria) arg1: ?x arg2: Syria Also conjunctive queries: population of capital of Syria Problem: Doesn’t support natural language input; using ASCS requires knowing some logic. AQUAINT 18 Month Meeting San Diego CA
How to Use ASCS in QUARK • Questions parsed by Gemini to yield logical form. • Logical form submitted to SNARK as conjecture. • Conjecture proved in application-domain theory. • Capabilities of ASCS and other sources advertised in theory. • ASCS provided with OAA wrapper. • Resources invoked as appropriate by procedural attachment. • Answer, as extracted from proof. • Presented textually • Visualization tool invoked AQUAINT 18 Month Meeting San Diego CA
“Show the capitals of Islamic countries that border Iraq.” Logical form produced by Gemini: (and country (?x) islamic (?x) bordering-relation (?z) goal (?z, iraq) source (?z, ?x) capital-of (?u, ?x) show (?v) patient (?v, ?u)) Answer: ?v AQUAINT 18 Month Meeting San Diego CA
Conjecture decomposed by SNARK To show a country is Islamic, use the axioms in the application-domain theory: if religions (?country, Muslim, ?percent) and ?percent > 50 then islamic (?country) if (SunniMuslim ?x, then Muslim ?x) A country that is more than 50 percent Muslim is Islamic. A SunniMuslim is a Muslim. AQUAINT 18 Month Meeting San Diego CA
ASCS Reveals Basic Facts • borders(Iraq, Syria) borders(Iraq, Turkey), ….. • religions(Syria, SunniMuslim, 74) religions(Syria, Christian, 10), … • capital(Syria, Damascus) AQUAINT 18 Month Meeting San Diego CA
Other Agents Reveal other Facts • Alexandria Digital Library Gazetteer: place-to-latlong(Damascus, capital, Syria; 33.5, 36.3) AQUAINT 18 Month Meeting San Diego CA
Answer visualization by Terrain ViewerDamascus (capital),Syria; 33.5,36.3 AQUAINT 18 Month Meeting San Diego CA
Future Plans • To move beyond single, one-off questions to scenario-based information-seeking dialogues. • Scenario description presents a sketch of a situation/problem; much is left unsaid. • To be filled out by a combination of application-domain theories and clarification/expansion dialogues. • Ground further question-answering on the resulting situation model. AQUAINT 18 Month Meeting San Diego CA