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Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Introduction to Ontologies Introduction.

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Presentation on theme: "Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Introduction to Ontologies Introduction."— Presentation transcript:

1 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Introduction to Ontologies Introduction – 5 min Motivation – 5 min Ontologies compared to other stuff – 5 min Exercise – first part – 15 min Upper ontology specifics – 15 min Exercise – second part – 15 min Discussion – 15 min Adam Pease Teknowledge

2 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Ground Rules Increasing interactivity as presentation goes on Discussion about philosophy, but not Philosophy –Practical goal of providing basic grounding in knowledge engineering –There are many alternatives, to make progress requires making choices and getting to work No such thing as a dumb question

3 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Definitions An ontology is a shared conceptualization of a domain An ontology is a set of definitions in a formal language for terms describing the world

4 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Motivation select EMPDAT from PERSTAB where POS=mgmnt –What does it mean? –PERSTAB is a table which lists employee data »Whats an employee? How is an employee different from a contractor? What if I want data on both? Even if this information is available in English, a human has to read it

5 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Motivation (2) "Parenthood is a more general relationship than motherhood." "Mary is the mother of Bill." "Who are Bill's parents? "Mary is the parent of Bill. –that fact is not stated anywhere, but can be derived by a DAML application. Example from Why Use DAML?

6 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Motivation (2) continued More formally stated, given the statements (motherOf subProperty parentOf) (Mary motherOf Bill) when stated in DAML, allows you to conclude (Mary parentOf Bill) Java code or a stored procedure could do this sort of inference for facts in XML or SQL But the DAML spec itself says the conclusion is true In contrast, different Java code could reach a different conclusion

7 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Motivation (2) continued (Mary motherOf Bill) (parentOf inverse childOf) (Bill childOf ?X) ?X = Mary The semantics of inverse is part of the DAML spec

8 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Language Formality and Expressiveness Formality Expressiveness Human Language KIF CycL OWL F-Logic DAML XML SQL Human Consumption Machine Processing Machine Inference

9 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Content Formality and Size Formality WordNet Cyc SUMO DOLCE LexiconsFormal Ontology Taxonomy Size SUMO+domain UMLS Yahoo!

10 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Everything is not a Nail Ontology is not always the right tool for the job Face recognition, vehicle control systems etc – not the right applications for ontology

11 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Many Ways to Use Ontology As an information engineering tool –Create a database schema –Map the schema to an upper ontology –Use the ontology as a set of reminders for additional information that should be included As more formal comments –Define an ontology that is used to create a DB or OO system –Use a theorem prover at design time to check for inconsistencies For taxonomic reasoning –Do limited run-time inference in Prolog, a description logic, or even Java For first order logical inference –Full-blown use of all the axioms at run time

12 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Upper Ontology An attempt to capture the most general and reusable terms and definitions

13 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Motivation Ontologies may have different names for the same things –type – a relation between a class and an instance –instance – a relation between a class and an instance –isa – a relation between a class and an instance –… Ontologies may have the same name for different things, and no corresponding terms –before – a relation between two time points –before – a relation between two time intervals Either use the same upper ontology, or at least map to a common upper ontology

14 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Formal Upper Ontologies DOLCE Cyc SUMO

15 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Simple Methodology Extract nouns and verbs from a source text Find classes in SUMO for the nouns and verbs Record a mapping as being either equal, subsuming or instance. –type a single word that relates to the UBL term in the "SUMO term" or "English Word" text areas in the SUMO browser Create a subclass of SUMO if it's a subsuming mapping Add properties to the subclass –reusing SUMO properties –extending SUMO properties by creating a &%subrelation of an existing property Add English definition to the class –define constraints that express how the subclass is more specific than the superclass Express the classes and properties in KIF and begin creating axioms, based on the English definitions created previously

16 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Exercise Walk through the process of creating some ontology content from a source text Learn a general methodology Get practical familiarity with KIF and SUMO

17 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 First Exercise (1) Seven Turkish nationals of Chechen origin hijacked a Russia-bound Panamanian ferry in Trabzon. The hijackers initially threatened to kill all Russians on board unless Chechen separatists being held in Dagestan, Russia, were released. On 19 January 1998, the hijackers surrendered to Turkish authorities outside the entrance to the Bosporus. The passengers were unharmed. Identify items that need formalization – start with nouns and verbs

18 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 First Exercise (2) Seven Turkish nationals of Chechen origin hijacked a Russia-bound Panamanian ferry in Trabzon. The hijackers initially threatened to kill all Russians on board unless Chechen separatists being held in Dagestan, Russia, were released. On 19 January 1998, the hijackers surrendered to Turkish authorities outside the entrance to the Bosporus. The passengers were unharmed. Now create terms that correspond to the nouns and verbs Remove redundancy Are there any background notions that are not explicit in the text?

19 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 First Exercise (3) Seven Turkish nationals of Chechen origin hijacked a Russia- bound Panamanian ferry in Trabzon. The hijackers initially threatened to kill all Russians on board unless Chechen separatists being held in Dagestan, Russia, were released. On 19 January 1998, the hijackers surrendered to Turkish authorities outside the entrance to the Bosporus. The passengers were unharmed Turkey, Chechnya, Nationality, Hijacking, Threatening, Killing, Releasing, Holding, Dagestan, Russia, Separatist, Entrance, Bosporus, Unharmed, Panama, Trabzon, Authority, Outside, boundFor, Ferry, onBoard

20 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 SUMO Overview Understanding whats in the upper ontology, in order to use it effectively

21 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 High Level Distinctions The first fundamental distinction is that between Physical (things which have a position in space/time) and Abstract (things which dont) Physical Abstract

22 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 High Level Distinctions Partition of Physical into Objects and Processes Physical Object Process

23 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Objects Object SelfConnectedObject Substance CorpuscularObject Region Collection

24 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Processes DualObjectProcess Substituting Transaction Comparing Attaching Detaching Combining Separating InternalChange BiologicalProcess QuantityChange Damaging ChemicalProcess SurfaceChange Creation StateChange ShapeChange IntentionalProcess IntentionalPsychologicalProcess RecreationOrExercise OrganizationalProcess Guiding Keeping Maintaining Repairing Poking ContentDevelopment Making Searching SocialInteraction Maneuver Motion BodyMotion DirectionChange Transfer Transportation Radiating

25 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Abstract SetOrClass Relation Proposition Quantity Number PhysicalQuantity Attribute Graph GraphElement

26 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 A Little Bit of Logic Instance – GeorgeBush, Iraq, BobsRightBigToe Class – Human, Nation Relation – WWI before WWII, Bill childOf Mary => (read as implies) - if X then Y and – X and Y are true or – X or Y (or both) are true not – not X – the opposite of the truth of X exists ?X – there exists something about which the following is true

27 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 A Little Structural Ontology (instance GeorgeBush Human) – GeorgeBush is an instance of the class of humans (exists (?X) (parent ?X GeorgeBush)) – there exists something of which George Bush is the parent (instance parent BinaryPredicate) – the relation of parent is a binary relation (domain parent 1 Organism) – the first argument to the parent relation must be an instance of the class Organism (domain parent 2 Organism) – similarly for the second argument

28 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Linking to SUMO Terms Nation, Confining, Committing, SocialRole, TransportationDevice, Killing, Near, Injuring, citizen, (not…), (exists…) Terms from the exercise (may or may not be the same as SUMO terms): –Turkey, Chechnya, Nationality, Hijacking, Threatening, Killing, Releasing, Holding, Dagestan, Russia, Separatist, Entrance, Bosporus, Unharmed, Panama, Trabzon, Authority, Outside, boundFor, Ferry, onBoard Use the terms in the first bullet to define the terms in the second bullet –Use Nation to state: (instance Turkey Nation)

29 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Formalization (exists (?TURK …) (and (citizen ?TURK Turkey)) … )

30 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Formalization (exists (?TURK ?FERRY …) (and (citizen ?TURK Turkey) (instance ?FERRY FerryBoat) … )

31 Permission to reuse granted so long as this notice is not altered – Author: Adam Pease 2003 Formalization (exists (?TURK ?FERRY ?HIJACK) (and (citizen ?TURK Turkey) (instance ?FERRY FerryBoat) (instance ?HIJACK Hijacking) (agent ?HIJACK ?TURK) (patient ?HIJACK ?FERRY) (earlier ?HIJACK (DayFn 19 (MonthFn January (YearFn 1998))))))


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