Submissions:Faceted Classification Scheme

From Odp

This article has assigned reviews
Review about this article has been done.
Jump to: navigation, search


This pattern has been certified.

Related submission, with evaluation history, can be found here

If you are a member of quality committee please visit the

evaluation section

If you are author of this proposal or you want to contribute to this pattern's review, you can:

In general, it could be useful to visit the evaluation section to have informations about the evaluation process of this proposal

Current revision ID: 10104

General information

Name Faceted Classification Scheme (FCS)
Problem Ontological representation of a specific domain concept conceptualized using a Faceted Classification Scheme (FCS).


Non-Ontological Resource

Description A FCS is defined as: "a set of mutually exclusive and jointly exhaustive categories, each made by isolating one perspective on the items (a facet), that combine to completely describe all the objects in question, and which users can use, by searching and browsing, to find what they need" (Denton, 2003).

The following notation is introduced to refer to the elements of a generic FCS in the figure below:

  • Target Domain Concept (TDC) denotes the domain of discourse. The domain-specific concept targeted by the FCS.
  • Facet_i denotes one of the facets of the FCS.
  • F_iTerm_j denotes one of the terms of Facet_i.
  • Item_x denotes one the items from the domain of discourse (TDC) to be classified.
Graphical Representation

Diagram

Image:FacetedClassificationScheme_GenericStructure.png


Ontology

Description Generic structure of the Normalization ODP used to represent a Faceted Classification Scheme (FCS).
The symbol (≡) denotes an OWL defined class.
The symbol (≡) denotes an OWL defined class.

The figure below represents a further generalization of the Normalization ODP and introduces the following notation:

  • :TDC denotes a primitive class representing the domain concept being normalized.
  • :Module_i denotes a primitive class that represents one of the modules.
  • :M_iClass_j denotes a primitive class that represents a subset of the module class :Module_i.
  • :hasModule_i denotes an object property that links every module :Module_i to the different subclasses of the target domain concept :M_iClass_jTDC and :SpecificTDC_x.
  • :M_iClass_jTDC denotes a defined class that represents a subset of the target domain concept class :TDC. Every class :M_iClass_jTDC is defined based on its relationship to the single corresponding class :M_iClass_j that it is derived from.
  • :SpecificTDC_x denotes a primitive class that represents a subset of the target domain concept class :TDC and an entity from the domain to be classified. Every class :SpecificTDC_x is described based on its relationship to various classes :M_iClass_j from potentially different modules. As a consequence of this relationship, the classes :SpecificTDC_x could introduce the polyhierarchy scenarios in the ontology model that the Normalization ODP aims to manage and untangle.

The implementation of a generic defined class :M_iClass_jTDC is given as follows:

:M_iClass_jTDC rdf:type owl:Class ;
               rdfs:subClassOf :TDC ;
               owl:equivalentClass [ rdf:type owl:Restriction ;
                                     owl:onProperty :hasModule_i ;
                                     owl:someValuesFrom :M_iClass_j
                                   ] .

The implementation of a generic class :SpecificTDC_x is given as follows:

:SpecificTDC_x rdf:type owl:Class ;
               rdfs:subClassOf :TDC ,
                               [ rdf:type owl:Restriction ;
                                 owl:onProperty :hasModule_i ;
                                 owl:someValuesFrom :M_iClass_j
                               ] ,
                               [ ... rest of existential restrictions on property :hasModule_i
                                     for every class :M_iClass_j that participates
                                     in the description of :SpecificTDC_x
                               ] .

This implementation of the classes :M_iClass_jTDC and :SpecificTDC_x respectively, enable a reasoner to infer and maintain the subsumption relations between a given class :SpecificTDC_x and the various classes :M_iClass_jTDC that it is related to.

Graphical Representation

Diagram

Image:NormalizationGenericStructure2.png


Process

Description Mapping between the elements in the generic structure of a Faceted Classification Scheme and the Normalization ODP.

The table below summarizes the alignment of the elements in the generic structure of both conceptual models. This alignment enables the conversion from a FCS to an OWL DL ontology by applying the Normalization ODP:

  • The first column (leftmost), contains the elements of a generic FCS as introduced in section Non-Ontological Resource above.
  • The second column contains the elements of the Normalization ODP generic structure

as introduced in section Ontology above.

  • The third column represents the selected OWL notation for the elements of a generic FCS in the context of the Normalization ODP generic structure.
  • The forth column (rightmost), indicates the OWL implementation chosen for every element. The selection complies with the requirements of the normalization mechanism.

Based on the principle of representating each facet of a FCS as a module of the Normalization ODP, the underlying ideas behind the mappings in the figure(table) above can be outlined as follows:

  • The target domain concept TDC represents the domain of discourse of both a FCS and the Normalization ODP. The primitive class :TDC fulfills that role in the normalized ontology.
  • A facet Facet_i from a generic FCS corresponds to a module :Module_i in the Normalization ODP, therefore it becomes a primitive class :Facet_i in the normalized ontology model.
  • A facet Facet_i from a FCS also becomes an object property :hasFacet_i in the normalized ontology, given that for every module :Module_i in the Normalization ODP, there is an object property :has_Module_i.
  • From the relationship between facet and module, it follows that a facet term F_iTerm_j from a FCS maps to a module subclass :M_iClass_j from the Normalization ODP. Both elements represents the same notion in their respective conceptual models. A subvidision, a refinement of the facet or module that they complement respectively. Therefore, a facet term F_iTerm_j from a FCS becomes a primitive class :F_iTerm_j in the normalized ontology.
  • A facet term F_iTerm_j from a FCS also produces a defined class :F_iTerm_jTDC in the normalized ontology, given that for every primitive class :M_iClass_j in the Normalization ODP, there is a corresponding defined class :M_iClass_jTDC.
  • Every item Item_x to be classified in the FCS aligns to a class :Specific_x that is automatically classified by a reasoner in the Normalization ODP. Therefore, every element Item_x is represented as a primitive class :SpecificTDC_x in the normalized ontology.
Graphical Representation

Diagram

Image:FacetedClassificationSchemeGenericStructure.png


Scenario example

Description To create an ontology model to represent an existing Faceted Classification Scheme for a specific domain concept.


Example of a Non-Ontological Resource

Description The figure below recaps the final FCS developed for the "Dishwashing Detergent" domain example in (Denton, 2003)(§ 2.4). The elements of the schema fit into the generic structure of a FCS presented in section Non-Ontological Resource earlier, where:
  • The TDC element is populated with the domain "Dishwashing Detergent".
  • Facet_i elements are populated with the facets: "Agent", "Form", "Brand Name", "Scent", "Effect On Agent", and "Special Property".
  • F_iTerm_j elements are populated with the terms or foci listed below (grouped by facet):
    • Agent: dishwasher, person.
    • Form: gel, gelpac, liquid, powder, tablet.
    • Brand Name: Cascade, Electrasol, Ivory, No Name, Palmolive, President's Choice, Sunlight.
    • Scent: green apple, green tea, lavender, lemon, mandarin, ocean breeze, orange blossom, orchard fresh, passion flower, ruby red grapefruit, ylang ylang.
    • Effect on Agent: aroma therapy (subdivisions: invigorating, relaxing).
    • Special Property: antibacterial.
  • Item_x elements are populated in this case with two example items to classify:
    • "President's Choice Antibacterial Hand Soap and Dishwashing Liquid".
    • "Palmolive Aroma Therapy, Lavender and Ylang Ylang".

To illustrate the representation of a specific dishwashing detergent, let us reuse the two classification examples presented in (Denton, 2003)(§ 2.4). Applying the "Dishwashing Detergent" FCS developed in the cited reference, the item "President's Choice Antibacterial Hand Soap and Dishwashing Liquid" is classified as follows:

  • Agent: person
  • Form: liquid
  • Brand Name: President's Choice
  • Scent: (none)
  • Effect on Agent: (none)
  • Special Property: antibacterial

The item "Palmolive Aroma Therapy, Lavender and Ylang Ylang," is classified as:

  • Agent: person
  • Form: liquid
  • Brand Name: Palmolive
  • Scent: lavender, ylang ylang
  • Effect on Agent: aroma therapy
  • Special Property: (none)
Graphical Representation

Diagram

Image:Denton_-_2003_-_FCS_Dishwashing_Detergent.jpg

Web Reference http://www.miskatonic.org/library/facet-web-howto.html


Ontology example

Description OWL representation of the "Dishwashing Detergent" domain concept Faceted Classification Scheme applying the Normalization ODP.
List of object properties.
List of object properties.

The symbol (≡) denotes an OWL defined class.

Graphical Representation

Diagram

Image:FacetedClassificationStructureOntologyExample.png

Web Reference http://dl.dropbox.com/u/1666716/Attachments/detergent_fcs_normalisation_prot3x_owl.owl


Process example

Description According to the guidelines derived from the table in section Process above and the implementation of a class :SpecificTDC_x given in section Ontology above, the description of the example detergent "President's Choice Antibacterial Hand Soap & Dishwashing Liquid" in the normalized ontology can be stated as follows:
:PresidentsPersonLiquidAntibacterial
    rdf:type owl:Class ;
    rdfs:subClassOf :DishDetergent ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasAgent ;
                      owl:someValuesFrom :Person
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasForm ;
                      owl:someValuesFrom :Liquid
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasBrandName ;
                      owl:someValuesFrom :PresidentsChoice
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasSpecialProperty ;
                      owl:someValuesFrom :Antibacterial
                    ] .

The description of the example detergent "Palmolive Aroma Therapy, Lavender and Ylang Ylang," would be:

:PalmoliveAromaTherapyLavenderYlangYlang
    rdf:type owl:Class ;
    rdfs:subClassOf :DishDetergent ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasAgent ;
                      owl:someValuesFrom :Person
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasForm ;
                      owl:someValuesFrom :Liquid
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasBrandName ;
                      owl:someValuesFrom :Palmolive
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasScent ;
                      owl:someValuesFrom :Lavender
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasScent ;
                      owl:someValuesFrom :YlangYlang
                    ] ,
                    [ rdf:type owl:Restriction ;
                      owl:onProperty :hasEffectOnAgent ;
                      owl:someValuesFrom :AromaTherapy
                    ] .
Graphical Representation

Diagram

Image:MappingFCSNormalizationODP.png


About

SubmittedBy BenedictoRodriguezCastro
Author BenedictoRodriguezCastro, HughGlaser, LesCarr
Also known as
Known uses
Related to Submissions:Normalization, Submissions:Partition, Submissions:ClassAsPropertyValue
Other References

Additional information

Scenarios

Scenarios about Faceted Classification Scheme

No scenario is added to this Content OP.

Reviews

Reviews about Faceted Classification Scheme
Review article Posted on About revision (current is 10104)
RimDJEDIDI about Faceted Classification Scheme 245545515 September 2010 1006710,067
AndreaNuzzolese about Faceted Classification Scheme 245546020 September 2010 1010410,104
BorisVillazón-Terrazas about Faceted Classification Scheme 245545717 September 2010 1010410,104
VojtechSvatek about Faceted Classification Scheme 245545717 September 2010 1010410,104

This revision (revision ID 10104) takes in account the reviews: none

Other info at evaluation tab


Modeling issues

Modeling issues about Faceted Classification Scheme
Modeling issue Competency question Domains
Multiple Alternative Classification Criteria Allow me to retrieve all "elements" (classes/individuals) of a "domain concept" viewed by a combination of "values" (or "terms") from various "classification criteria" (or "facets").
View Inheritance For example
in the case of the representation of the "wine" domain concept:
  • Allow me to select a bottle of wine by color
    region
    flavour and(or) ocassion.

In the case of the representation of the "pizza" domain concept:

  • Allow me to select a pizza based on the type of base
    the toppings and(or) the name.


References

Add a reference

  • Normalization Ontology Design Pattern Documentation | reference page
  • Spiteri, Louise. A simplified model for facet analysis: Ranganathan 101. Canadian Journal of Information and Library Science, 23(1/2):1-30, 1998. Documentation | reference page
  • Egana-Aranguren, Mikel. Role and Application of Ontology Design Patterns in Bio-ontologies. PhD thesis, School of Computer Science, University of Manchester, 2009. Documentation | reference page
  • Denton, William. How to Make a Faceted Classification and Put It On the Web. Nov 2003. Documentation | reference page
  • Rodriguez-Castro, B., Glaser, H. and Carr, L. (2010) How to Reuse a Faceted Classification and Put it on the Semantic Web. In: The 9th International Semantic Web Conference (ISWC), November 2010, Shanghai, China. Documentation | reference page
  • Alan L. Rector. Modularisation of domain ontologies implemented in description logics and related formalisms including owl. In K-CAP '03: Proceedings of the 2nd international conference on Knowledge capture, pages 121{128, New York, NY, USA, 2003. ACM. ISBN 1-58113-583-1. Documentation | reference page


Submission to event

WOP:2010

Personal tools
Quality Committee
Content OP publishers