Guidelines to create an ontology
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Transcript of Guidelines to create an ontology
Guidelines to Create an Ontology
Presenters :-
• Nisitha Manukulasuriya
• Rajith Premabandu
• Isuru Dilshan1
Overview• Designing a good Ontology
• Methods
• Basic Idea
• Ontology’s content
• Explanation of the guidelines by examples
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Content• What is an Ontology
• Why Ontology ?
• What is in Ontology
• Methodology
• Basic Ideas
• Building the Ontology
• Taxonomy Evaluation
• E commerce Ontology Example
• Banking Ontology Example
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What is an ontology
• “An ontology is a formal, explicit specification of a shared conceptualization”
• conceptualization
• explicit
• formal
• shared
• “An ontology is a formal, explicit specification of a shared conceptualization”
• conceptualization
• explicit
• formal
• shared 4
Why ontology ?
• Share common understanding of the domain and the related information
• To reuse knowledge
• To analyse domain knowledge
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What is in Ontology
• Classes
• Relation
• Attributes
• Formal axioms
• Functions
• Instances 6
Methodology
• Define concept
• Organize them to taxonomy
• Define relations among the classes
• Define attributes and their values
• Define instances
• Define axioms and function7
Basic ideas
• Yours will be different from mine
• Iterative process
• Initially, start with nouns and verbs
• A noun will be a class, attribute or instance
• A verb will be the relation
• Iterations are needed to further clarification8
Building the ontology
• Determine the domain and the scope of the ontology
• Which domain are you thinking of?
• Is it going to be just one, or will you need different sub ontologies to make it clearer?
• Who will use the ontology?
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Building the ontology …• Sources to use
• Experts
• Ask everything want to know
• Always keep manners
• Grab their terminology
• Documents
• literatures, documents, technical information, etc.
• Highlight underlying nouns and verbs
• Existing ontologies
• You are not the first one to think about that domain
• Existing ontologies can be fully or partially reused 10
Building the ontology …
• Enumerate important terms
• List all nouns and verbs
• For each noun note down
• name, synonym, a natural language description, source
• Decide whether the noun is a class, attribute or instance
• Verbs will end up as relations
• The iterative process will may uncover some other concepts too
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Building the ontology …• Classify the concepts in a hierarchy.
• Use either top-down or bottom-up or combination of processes
• Hierarchical relations
• Subclass
• Disjoint decomposition
• Exhaustive decomposition
• Partition 12
Building the ontology …• Define relations
• Describe each hand made diagram and the relations in detail
• Define attributes
• Well defined type is an attribute, not a class
• Attach the attribute to the most general class/concept that can have that property
• Define attribute type13
Building the ontology …
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• Define attributes …
• Try to define range, value, precision, related classes
• Define instances
• A specific noun
• Described in detail
Taxonomy Evaluation
• Class definition evaluation
• Synonyms for the same concept do not represent different classes
• A class is not only real entities in the domain
• Keep a balance with subclasses
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Taxonomy Evaluation …
• Class Hierarchy
• Avoid class cycles
• Be careful of classifying classes where they do not belong
• Careful with your classification
• Careful with incompleteness of taxonomies
• Redundancy
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Taxonomy Evaluation …
• Other Hints
• Forget the implementation level
• Do not use “reserved” words in your names
• Choose a naming convention
• Limit the scope
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Up to here
• What is an Ontology
• Why Ontology
• What is in Ontology
• Methodology
• Building an Ontology
• Taxonomy Evaluation
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Example 1E-Commerce Ontology
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E-commerce Ontology• What is e-commerce ?
• Description
• E commerce is used via computer networks such as internet. Several organizations involve in this process. Venture capital firm supplies Venture Capital ,financial support to establish such companies. Venture capital invests a large amount of currency to enable startup for a company. Company is also an organization that issues shares and shareholders buy shares to own a part of the company. A Share is an unit of capital that has price. CEO is a person who manages the company. A Company consists of B2B and B2C companies. A B2B transaction has an amount which is higher than B2C transactions.
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Listing NounsListing Verbs
NounName
Synonyms Acronyms Description Source
Organization OrganisationAssociation
Org A commercial or industrial enterprise with a group of people ,systematically structured to accomplish an overall common goal.
Description
Person Human Unspecified individual with certain capabilities & responsibilities separate from others.
Description
VentureCapital
Financial supportFunding
VC Money provided by investors to start up firms in early stages of high potential .high risk growth companies.
Description
Venture Capital Firm
Venture Capitalist
Firms that provides start up or capitals / loans to promising ventures for long term growth potential.
Description
Company FirmCorporation
COCorp
Any business organization which has focus of gaining
profits.
Description
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Unspecified individual with certain capabilities & responsibilities separate from others.
Money provided by investors to start up firms in early stages of high potential high risk growth companies
Firms that provides start up or capitals / loans to promising ventures for long term growth potential.
A commercial or industrial enterprise with a group of people, systematically structured to accomplish an overall common goal.
Any business organization which has focus of gaining profits
Describe nouns
Identify Concepts
• Concepts
• Organization
• Venture Capital Firm
• Venture Capital
• Person
• Company
• CEO
• Share
• Share Holders
• B2B
• B2C
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Identify Relations
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Venture Capital
amount:currency
CompanyShares
price:Currency issues
Shareholders
owns
Venture capital Firm supplies
CEO
Name:stringmanages
Identify Attributes
• Class Venture Capital
• Amount : currency
• Period : date/time
• Class Company
• Name : string
• Address : string
• Property Names : string
• Profit : currency
• Capital: currency
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Identify Instances• E.g.
• “Meg Whitman is the CEO of the B2C company ebay.com.”
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Person
age:Integer…CEO
Name:string
Company
B2C
manages
Instance Of
Meg Whiteman
Instance Of ebay.com
Organization
Venture capital Firm
Venture Capital
amount:currency
Person
age:Integer…
CEO
Name:string
Shareholders
Shares
price:Currency
Company
B2CB2B
price: currency
managesissuesowns
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supplies
Taxonomy Evaluation
• Every Class refers to only one noun.
• Haven’t used reserved key words.
• Class hierarchy well-balanced.
• Classes Don’t have Cycles.
• Used a Standard.
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Up to now ……
• Identify Nouns
• Identify Verbs
• Define relations
• Identify Attributes
• Identify Instances
• Taxonomy Evaluation28
Example 2Banking Ontology
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Banking Ontology
• Description
• There are several processes in a banking domain. An account holder owns several bank accounts. These accounts are identified with a unique account number. There are two types of accounts, current and savings. Bank account offers two kinds of loans. They are personal and educational loans. Bank account has compound interest and simple interest. A payment can be done to a bank account via cheque , cash or EFT. A payment has a date. When a payment is done a transaction is occurred. A transaction is a deposit or
withdraw. 30
Listing NounsListing Verbs
Banking Ontology
• Description …
• An account holder is uniquely identified by an identification number and the address, monthly expense, NIC number are recorded. Current accounts should maintain a minimum balance and a penalty is calculated for the decrease of the minimum balance. Bank account calculate interest in various time periods. This vary with the bank. A cheque has a cheque number, amount, date, payee, bank name. A cash payment is done by the currency used. ETF payment has a sender and receiver account numbers.
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Listing NounsListing Verbs
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Noun Synonyms Acronyms Description Source
Accountholder
- AH Member which administrates Global accounts.
Description
Bank Account
- BA financial account recording the financial transactions between the customer and the bank and the resulting financial position of the customer with the bank
Description
SavingsAccount
- A bank account that earns interest
Description
CurrentAccount
- These accounts are maintained by the corporate clients that may be operated any number of times in a day.
Description
Describe nouns
Identifying Concepts
• Cheque
• Cash
• EFT
• Method of Payment
• Transaction
• Payment
• Deposit
• Withdraw
• Compound interest
• Simple interest
• Interest
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• Bank Account
• Account Holder
• Savings Account
• Current Account
• Loan
• Personal Loan
• Educational Loan
Identify Relations
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Payment
amount:currency
Method of Payment
Is donevia
Account holder
id:String
Bank account
accNo:String
Bank account
accNo:String
Loan
amount:doubleperiod:int
offer
Payment
amount:currency
Transaction
ammount:doubledate:date
occurs
Defining attributes
• Class Cheque• cheque number: String
• amount: currency
• Date: Date/Time
• Payee: String
• Bank: String
• Name: String
• Class Account holder• identification number :String
• address :String
• monthly expense :currency
• nic No:String
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Account holder
id:String
Bank account
accNo:String
Savings
Current
minBal:float
Personal
houseExpence:double
Educational
purpose:String
Compound
calIntrest()
Simple
calIntrest()
Payment
amount:currency
Cheque
chequeNo:String
Cash
ammount:double
EFT
amount:double
sendAcknoledgement()
Transaction
ammount:doubledate:date
Deposit
Withdraw
Method of Payment
Loan
amount:doubleperiod:int
Interest
rate:float
Is donevia
has a
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Synonyms for same concept do not represent different classes
Keep a balance with subclasses Avoid class cycles
Be careful of classifying classes where they do not belong
Careful with your classification
Careful with incompleteness of taxonomies
Do not use reserved words
Redundancy
Taxonomy Evaluation …
Gene Ontology
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Summary
• Guidelines• What is an Ontology • Why Ontology ?• What is in Ontology• Methodology• Basic Ideas• Building the Ontology• Taxonomy Evaluation
• E Commerce Ontology Example
• Banking Ontology Example 39
References
• A Simplified Guideto Create an Ontology
• Julita Bermejo
• ASLab R-2007-004 v 0.1 Draft
• May 22, 2007
• An Ontology-based Method and Tool for Cross-Domain Requirements Visualization
• Nirav Ajmeri, Kumar Vidhani, Manoj Bhat, SmitaGhaisas
Tata Research Development and Design Centre
A Division of Tata Consultancy Services
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References …
• http://www.geneontology.org
• Accessed on: 21 January 2012
• http://musicontology.com
• Accessed on: 20 January 2012
• http://en.wikipedia.org/wiki/Axiomatic_system
• Accessed on: 22January 2012
• http://www.iqlue.com/Ontology.pdf
• Accessed on: 21 January 2012
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Any Questions ?
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