october 19, 20051 the semantic web: what is it and why should you care? semantic arts, inc. dave...
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October 19, 2005 1
The Semantic Web:What is it and why should you care?
Semantic Arts, Inc.
Dave McComb
for Toronto IRMAC/DAMA Oct 19, 2005
October 19, 2005 2
Objectives
Semantics > Good Definitions
Exotic Terminology
Pursue this further
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Discipline
Standards
Tools
Con
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Infr
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Semantic Web
Semantic Technology
Semantic Methodology,
Design & Approach
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Discipline
Standards
Tools
Con
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Infr
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Part 1: Intro, Concepts and
Methods
Part 2: Semantic Metadata and
Annotated Data
Part 3: Semantic Web
Part 4: Demos
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Semantic Concepts, Discipline and Methods
Discipline
Standards
Tools
Con
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Infr
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Part 1: Intro, Concepts and
Methods
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Semantics
The study of meaning(sometimes the study of
the meaning of words)
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October 19, 2005 9
Structure and Metadata
You can now deal with thousands, even millions of transactions, by knowing only a small amount of metadata
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Drowning in Metadata
Thousands -> millions of bits of metadata
Meta metadata?XMI/MOF/CWM Millions ->
Billions of instances in hundreds of databases
Commit to share ontologies to get back to thousands/ tens of thousands of concepts
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Operative SemanticsSome of these fields are “known” to the system and cause overt changes in
behavior
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Others are more subtle
This one shows up on the detailed P&L
reports
This one shows up in the AP list of bills
to pay
This one shows up on the check
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None of this is mentioned in the user manual or on line help text
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Scale issues
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Carver Mead
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Flat Earth Schema
We need to get up out of the weeds
Higher level, business concepts
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Semantic Framework
Prime
CategoryContext
ContextCategory
October 19, 2005 18
Anna wierzbicka
Semantics: Primes and Universals
Anna Wierzbicka
October 19, 2005 19
Semantic PrimesPrime
CategoryContext
ContextCategory
Anna Wierzbicka
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First Prime
Discrete Physical Object– Something to which you could (potentially)
attach a unique bar code
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Physical Items
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Semantic Primes for Business
– People– Animals– Physical Made Items– Buildings– Landmarks– Physical Container– Homogenous
Material– Legal Entities– Historical Events– Conversion– Scheduled Events– Defined Events– Measurement– Estimate
– Monetary Amount– Reference Value– Decision– Request – Rights– Permission– Offer– Order (Directive)– Contract/Order– Messages– Documents– Inventions– Programs
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“G’arn?”“Narn”
Role of context
October 19, 2005 24
Context
How many addresses do you have in your database?One of our clients has 116.
Prime
CategoryContext
ContextCategory
How many types of addresses are there?
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Context
WhereWhenRelationshipsPurpose
Prime
CategoryContext
ContextCategory
What differentiates the 116?
Context, such as
October 19, 2005 26
CategoriesPrime
CategoryContext
ContextCategory
How Categories Inform Us
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Example CategoriesInventory system (categories disguised as attributes):
Attractive
Insurance spare
Fast/Slow Moving
A/B/C
High/Low Value
Degradable
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Example CategoriesInventory system (categories disguised as entities):
Equipment
Kits
Parts
Tools
Serialized Parts
Raw Material
Assemblies
Phantoms
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Example CategoriesInventory system (categories disguised as states):
Obsolete
Reserved
Out of Stock
In Inspection
Discontinued
On Order
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Example CategoriesInventory system (categories disguised as relations):
On consignment
In Use
Stock for this warehouse
Preferred Supplier
Issued to
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What are we doing???
We categorize things all the time.As data modelers we set up other people’s
categories for them.We decide whether their categories will be
expressed as:– Entities– Attributes (codes, enums, flags and labels)– States– Relations– Classes – Types– etc.
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Category Definition
Encarta: “a group or set of things, people, or actions that are classified together because of common characteristics”
Cambridge (English): “a type, or a group of things having some features that are the same”
Cambridge (American): ”a grouping of people or things by type in any systematic arrangement. (The light trucks weigh less than 5,000 pounds and are in a category that includes minivans, pickups, and sport utility vehicles)”
Infoplease: “any general or comprehensive division; a class”
Encyclopedia.com: “philosophical term that literally means predication or assertion”
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Operative Definition of Categories
Semantic Arts: “A description of a set of things that contains:
– A set of testable membership criteria that can either improve or reduce our confidence in the membership
– A set of additional information that can be inferred from the membership
– A set of behaviors that can be applied to members of the category
– A set of questions that can be applied to the instance to gather property or relationship values”
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Hidden Categories
Almost every “IF…THEN…” or “CASE…” statement contains a category
So does the procedures manualYou are aware of some of them
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Categories and Behavior
The reason to create a new category is if the distinction (the new category) will be treated differently, behaviorally– By a program, or– By a human
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Categories and Behavior
The reason to subsume categories (through a taxonomy or just collapse them) is if they can be treated the same, behaviorally
October 19, 2005 37
Wrap on Discipline
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Discipline
Standards
Tools
Con
ten
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Infr
astr
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Part 2: Semantic Metadata and
Annotated Data
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Metadata and Annotated Data
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Content: FOAF
Friend Of A Friend Ontology for contacts
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Content: Dublin Core
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So, how do we do this?
Business Vocabulary
Taxonomy
Ontology
Description Logic
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Business Vocabulary
Not whether, but – when:
• as you come across the terms, or up front?– what source:
• source documents, interviews or existing systems?
– how:• defining terms or concepts?
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Business Vocabulary
Schema Jargon
October 19, 2005 45
Injured workers -- representatives
Information contained in the claim files and records of injured workers, under the provisions of this title, shall be deemed confidential and shall not be open to public inspection (other than to public employees in the performance of their official duties), but representatives of a claimant, be it an individual or an organization, may review a claim file or receive specific information therefore upon the presentation of the signed authorization of the claimant.
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Employers -- Representatives
Employers or their duly authorized representatives may review any files of their own injured workers in connection with any pending claims.
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Claimant
A claimant may review his or her claim file if the director determines, pursuant to criteria adopted by rule, that the review is in the claimant's interest.
October 19, 2005 48
Patient
Except as otherwise provided by law, all treatment records shall remain confidential. Treatment records may be released only to the persons designated in this section, or to other persons designated in an informed written consent of the patient….[much more]
October 19, 2005 49
Child Victims
Information revealing the identity of child victims of sexual assault who are under age eighteen is confidential and not subject to public disclosure. Identifying information means the child victim's name, address, location, photograph, and in cases in which the child victim is a relative or stepchild of the alleged perpetrator, identification of the relationship between the child and the alleged perpetrator.
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Dilbert’s Boss Understands This
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“How to”
Sources– Documents– Existing systems– Controlled Vocabularies– Interviews
Techniques– Distinctionary– Concept -> Term
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Documents
Information contained in the claim files and records of injured workers, under the provisions of this title, shall be deemed confidential and shall not be open to public inspection (other than to public employees in the performance of their official duties), but representatives of a claimant, be it an individual or an organization, may review a claim file or receive specific information therefore upon the presentation of the signed authorization of the claimant.
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Existing systems
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Vocabulary Item:
“A variety of language unique to an individual”
Idiolect
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Every System We Design or Buy…
… is another ideolect
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Interviews
•Enumerate types•Look for counter examples•Look for similarities•Synonyms
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Warning:
Definitions are hard to get consensus onAnd often not worth it
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Example good Definition
Customer:Groups or individuals who have a business relationship with the organization--those who receive and use or are directly affected by the products and services of the organization. Customers include direct recipients of products and services, internal customers who produce services and products for final recipients, and other organizations and entities that interact with an organization to produce products and services.
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Another Problems with Definitions
Homonym problem– Same lexical word means different things
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SUMO and WordNet
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Concept
Avoids the generalized definition trapDrastically speeds up discovery (have you
ever tried to get a group of experts to agree on the meaning of a set of terms)
Finesses the homonymy problem
Term or Terms
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Process
Tease apart the facets of a given definition.People will generally agree with the facets.They won’t necessarily agree on the same
combination of facets mapping to the base word you started with.
Ask: what could we call each bundle of facets that they care about?
e.g., mother
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Key Concept: The Distinctionary
Is: a glossary
Is distinct from other glossaries: structurally, each definition first specifies the more general type of thing the word is, and then provides a way to distinguish this thing from others that are similar.
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Example
Patient:
A patient is a role between a human being and a healthcare delivery institution.
It is different from other roles between a human and a healthcare delivery institution in that the human had been the recipient of the delivery of diagnostic or corrective health care services.
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Taxonomies
Business Vocabulary
Taxonomy
Ontology
Description Logic
October 19, 2005 66
Taxonomy
“A taxonomy is a system for classifying and organizing large amounts of information”
Seth Earley www.earley.com
October 19, 2005 67
DMOZ
Home– Gardening– Personal Finance– Cooking
• Baking• Casseroles• Camping
– Dutch Oven
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Formal Taxonomy
Animalia
ArthopodaChordata
Mammalia
Carnivora
PantheraGenus
Species
Family
Order
Class
Phylum
Kingdom
Felidae
Ursus
(bears)leo
(lion)
tigris
(tiger)
isa?isa?
October 19, 2005 69
Subsumption v. Inheritance
Dynamic v. Static
+PaidToDate() : int+Reserve() : int
-pensionAmt : int
Pension
+ClaimMgr() : object+DaysLost() : int
-TimeLoss : bool-ReturnToWork : Date
Claim
October 19, 2005 70
Ontology --Frame based
Business Vocabulary
Taxonomy
Ontology
Description Logic
October 19, 2005 71
Ontology Definition
“A specification of a conceptualization”
Tom Gruber
Taxonomy: Ontology::Tree: Network
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Limits of Taxonomy
Disjointedness
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Concept: A Small Ontology
GP (Genealogy Primitives)PersonM/FSpouseParent
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Consider my family Database
MName FName Sex DoB EyeColor
Naomi John M 11/18/52 Grey
Betty William F 12/20/15 Hazel
Walter Crete M 11/15/17 Blue
Heidi Dave F 12/1/88 Blue
Naomi John M 4/3/54 Blue
Name
Dave
Naomi
John
Addie
Tommy
... ... ... ... ......
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What kinds of queries could I do?
Any view qualified by the attributes– (show everyone born before 1/1/1990)
Some join based queries– (show all of Dave’s children)
But it gets much more complex after that
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Committing to an Ontology
MName FName Sex DoB EyeColor
Naomi John M 11/18/52 Grey
Betty William F 12/20/15 Hazel
Walter Crete M 11/15/17 Blue
Heidi Dave F 12/1/88 Blue
Naomi John M 4/3/54 Blue
Name
Dave
Naomi
John
Addie
Tommy
... ... ... ... ......
Person
Person
Gender
PersonSpouse
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Concept: Committing & Sharing
GP (Genealogy Primitives)
GC (Genealogy Concepts)
My Family
Commits toCommits to
PersonM/FSpouseParent
Dave is maleDave is Addie’s parentAddie is femaleNaomi is Dave’s parentNaomi is Tom’s parent
Father…Uncle…Cousin…Second Cousin, etc. …
Key concept: queries/ inference can be executed using ontological definitions I’m not even aware of
October 19, 2005 79
Good Resource
Ontology Development 101: A Guide to creating your first ontology
Natalya Noy and Deborah McGuinnesshttp://www.ksl.stanford.edu/people/dlm/papers/ontology-tutorial-noy-mcguinness.pdf
October 19, 2005 80
Description Logics
Business Vocabulary
Taxonomy
Ontology
Description Logic
October 19, 2005 81
Description Logics
This is where the rigor comes in.
Three things that take some getting used to:– Classes and Instances interchangeable– Allowing the system to do some of the design
work for you– Open world logic
Plus some very strange terminology and symbology
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Description Logics (DL)Points of Departure
As much as possible, minimize the number of concepts that have to be accepted axiomatically.
Emphasize formal definitions for all the rest.
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DL Definitions
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Classes and Instances
Database designers make an early design decision as to what is going to be metadata (classes, columns, etc.) and what is going to be instance data.
For ontologists, this is a continually moving target.
Additionally, properties (which could be equivalent to attributes or relationships) are “free floating” and can be attached to classes, but don’t “belong” to them in the same way as with database models.
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Allowing the System to Do some Design
Declared
Inferred
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Open World
In closed world (i.e., SQL), absence of information is assumed to be negation. If the query doesn’t find it, it doesn’t exist.
In open world (DL), things are assumed to be possible until proven otherwise.
In DL, classes are assumed to overlap unless they are explicitly declared to be disjoint.
Domain and range are used for reasoning, not constraining.
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Motherhood
Sue is John’s biological motherSarah is John’s biological mother
Therefore?
George Washington’s mother
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Other strange vocabulary
DL Term English Description MeaningPartial Necessary Primitive, or
defined classesIf something is a member of this class then it is necessary to fulfill these conditions
Complete Necessary & Sufficient
Derived or defined classes
If something fulfills these conditions, then it is a member of this class
TBox Terms Metadata Reasoning in the ontology
ABox Assertions instances Reasoning over the data
October 19, 2005 90
Summary
Business Vocabulary
Taxonomy
Ontology
Description Logic
October 19, 2005 91
www.semanticarts.comSemantic Arts, Inc.