Proposed NWI Proposed NWI

KIF/CG --> Common Logic Standard A working group was recently formed from the KIF working

group. John Sowa is the only CG representative so far. – Stanford March 2002:

Agreed on the name: Common Logic Standard for First Order Logic Cris Menzel (U.Texas, Austin Philosophy dept) agreed to maintain a web

site, now called Conceptual Graphs and KIF to be reference implementations.

– KIF maintained by KIF working group, including Mike Genesereth who was the contact for requirements during its development.

– CG draft standard now available at a site maintained by John Sowa. Requirements are discussed in CGlist and at standards meetings at the annnual ICCS conference (2002, Bulgaria). Previously held in Canada, Germany, US, France.

– CG and KIF communities both contain competing vendors and academics. Other ISO logic standards to be described in relationship to

the Common Logic– Prolog Logic Programming Language (Mike Gruninger)– Object Constraint Language (under UML)– Z Formal Specification Language

Common Logic StandardCommon Logic Standard Will support:

– Institutionalization of KIF and CG Periodic versions instead of unscheduled ad-hoc changes will

encourage tools development Researchers and Developers can make requests of a standards body

rather than of individual caretakers, who may have business or professional interests to protect.

Contract requirements can specify differences from and extensions to the Common Logic standard used by vendor specific languages such as Cycorp’s Cyc-L, Ontos’ , XSB, Haley Eclipse, NASA CLIPS…)

– Specification of axiomatic ontologies– Selection of a knowledge representation language for a purpose

Expressivity/ computablility tradeoffs– Translation between formal languages

For changing vendors, user interfaces, performance problems

Common Logic in support of Common Logic in support of Axiomatized OntologiesAxiomatized Ontologies

Ontology working definition (Gruber)– Formal (to support automated inference)

explicit specification (concepts and relations are given terms and definitions)– of a shared conceptualization (abstract model relating people’s thinking to things in

the world (usually in a domain)

– A community with a shared conceptualization may have both a common natural language and domain ( Northumberland sheep herders ) or a common domain and different natural language ( Mathematics, logic?).

– (Gruninger and Lee) Ontology must capture the intended semantics of the users teminology.

• Not only ontology must capture meaning, but any component of an information system which has a human interpreter.

Ontology structure: hierarchy of concepts or classes and their relationships

Purpose: Capture world knowledge or (at least) domain understanding

Ontologies and Medical InformaticsOntologies and Medical Informatics Application example: creation of structured information from

medical texts:– Discharge Summaries– Requests– Patient Descriptions

Purpose: enable queries against the resulting database See Marie Rassineoux’s work for Geneva Hospital

– Application: creation of structured information from medical texts: Discharge Summaries, Requests, Patient Descriptions

– Purpose: to enable queries against the resulting database– Concept classes for NLP for Gastro-Intestinal Surgery

Root– Actor– Event– Attribute– Value– Temporal– Relationship

Cyc Upper Level Cyc Upper Level THING

– Individual Object Intangible Represented Thing

Event Stuff Intangible Object Collection

Lattice shaped

Relationship is an intangible thing, with slots.

Axioms expressed in Cyc-L, full first order logic, with second order extensions.

Supporting Ontologies Supporting Ontologies can connect an Information System can connect an Information System

to the world of the end user.to the world of the end user. Knowledge representations richer than SQL and

more accessible to the end user permit:– Formation of complex queries– Construction of templates for pattern matching and data mining in dense

information environments– Collaborative ontology maintenance – User participation in lexicon maintenance – Formation of queries against heterogenous databases, allowing their concepts

to be mapped using more general ones.

Upper Level Ontology: Upper Level Ontology: Standardize? Or Register & Standardize? Or Register &

MapMap Influences on Upper Levels– Philosophy– Linguistics– Pragmatics– Business Plans– Academic School of Thought– Domain Ontologies

Intensional approach (SUMO) needs agreement on theory Extensional approach (Gruber, FCA) mine data models,

documents, thesauri Registration of Ontologies

– 11179 Part 2 as a classification scheme– An ontology may be used to generate a data model or a value domain, either in whole or

in part. It may evolve more or less continuously, with the data model being regenerated less often. The linkage is not simple.

– DAML + OIL expect ontology mapping services on the web

Related Standards EffortsRelated Standards Efforts CSMF ISO/IEC 14481 FCD 12/1/98 -Proposed

to be withdrawn– Universe of Discourse for an enterprise and its users– Formal description for information systems design, interchange and

integration, defined using typed predicate logic– Entities, properties , relationships, constraints, inheritance mechanisms,

rules, events, functions, processes.– Issues overlap those of 11179 P.2

ISO TR 9007 SC32, 1987– Schema is independent of technology or platform.– Exchange of meaning requires agreeement

DAML– Proposed for description of ontologies governing semantics of web page

markup. Uses Description Logics and ontology mapping services.