tractable extensions of the description logic el with numerical datatypes
DESCRIPTION
We consider extensions of the lightweight description logic (DL) EL with numerical datatypes such as naturals, integers, rationals and reals equipped with relations such as equality and inequalities. It is well-known that the main reasoning problems for such DLs are decid- able in polynomial time provided that the datatypes enjoy the so-called convexity property. Unfortunately many combinations of the numerical relations violate convexity, which makes the usage of these datatypes rather limited in practice. In this paper, we make a more fine-grained complexity analysis of these DLs by considering restrictions not only on the kinds of relations that can be used in ontologies but also on their occurrences, such as allowing certain relations to appear only on the left- hand side of the axioms. To this end, we introduce a notion of safety for a numerical datatype with restrictions (NDR) which guarantees tractabil- ity, extend the EL reasoning algorithm to these cases, and provide a complete classification of safe NDRs for natural numbers, integers, ra- tionals and reals.TRANSCRIPT
TRACTABLE EXTENSIONS OF THE DESCRIPTION
LOGIC EL WITH NUMERICAL DATATYPES
Despoina Magka, Yevgeny Kazakov and Ian Horrocks
Oxford University Computing Laboratory
July 16, 2010
Introduction
OUTLINE
1 INTRODUCTION
2 REASONING IN EL⊥(D)
3 CONCLUSION
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 2/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGIES
Ontologies are formal descriptions of domains such as:
Aerospace
Cellular biology
Human anatomy
Drugs
Applications:
Automated decision support
Reference databases
. . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 3/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:
Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
Paracetamol
PatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:
Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatient
A drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:
Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tablet
A patient who has age less than 6 yearsAxioms formulate properties and restrictions using terms:
Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:
Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:
Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.
Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.
Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.
[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:
500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:500 mg
more than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:500 mgmore than 250 mg
less than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
ONTOLOGY AXIOMS
Terms describe entities from specific domains, e.g. for adrug ontology:
ParacetamolPatientA drug that contains 500 mg of paracetamol per tabletA patient who has age less than 6 years
Axioms formulate properties and restrictions using terms:Panadol is a drug.Panadol contains paracetamol.Panadol contains 500 mg of paracetamol per tablet.[A patient who has age less than 6 years] should not beprescribed anything which [contains more than 250 mg ofparacetamol per tablet].
Restrictions specify ranges of data values:500 mgmore than 250 mgless than 6 years
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 4/20
Introduction
DESCRIPTION LOGICS
Formally describe axioms:
EXAMPLEPanadol v DrugPanadol v ∃contains.ParacetamolPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])Patient u ∃hasAge.[< 6] u ∃hasPrescription.
∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Atomic conceptsAtomic rolesDatatype restrictionsConcept constructorsFoundations of W3C ontology languages (OWL and OWL 2)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 5/20
Introduction
DESCRIPTION LOGICS
Formally describe axioms:
EXAMPLEPanadol v DrugPanadol v ∃contains.ParacetamolPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])Patient u ∃hasAge.[< 6] u ∃hasPrescription.
∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Atomic concepts
Atomic rolesDatatype restrictionsConcept constructorsFoundations of W3C ontology languages (OWL and OWL 2)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 5/20
Introduction
DESCRIPTION LOGICS
Formally describe axioms:
EXAMPLEPanadol v DrugPanadol v ∃contains.ParacetamolPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])Patient u ∃hasAge.[< 6] u ∃hasPrescription.
∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Atomic conceptsAtomic roles
Datatype restrictionsConcept constructorsFoundations of W3C ontology languages (OWL and OWL 2)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 5/20
Introduction
DESCRIPTION LOGICS
Formally describe axioms:
EXAMPLEPanadol v DrugPanadol v ∃contains.ParacetamolPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])Patient u ∃hasAge.[< 6] u ∃hasPrescription.
∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Atomic conceptsAtomic rolesDatatype restrictions
Concept constructorsFoundations of W3C ontology languages (OWL and OWL 2)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 5/20
Introduction
DESCRIPTION LOGICS
Formally describe axioms:
EXAMPLEPanadol v DrugPanadol v ∃contains.ParacetamolPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])Patient u ∃hasAge.[< 6] u ∃hasPrescription.
∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Atomic conceptsAtomic rolesDatatype restrictionsConcept constructors
Foundations of W3C ontology languages (OWL and OWL 2)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 5/20
Introduction
DESCRIPTION LOGICS
Formally describe axioms:
EXAMPLEPanadol v DrugPanadol v ∃contains.ParacetamolPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])Patient u ∃hasAge.[< 6] u ∃hasPrescription.
∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Atomic conceptsAtomic rolesDatatype restrictionsConcept constructorsFoundations of W3C ontology languages (OWL and OWL 2)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 5/20
Introduction
DESCRIPTION LOGICS REASONING
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Can Panadol be prescribed to a 3-year-old patient?- Is X satisfiable?DL reasoning tasks:
Check satisfiability of a concept (O |= X v ⊥)Check satisfiability of an ontology (O |= ⊥ )Check subsumption (O |= A v B)Classification (compute all A v B such that O |= A v B) more general than all tasks above
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 6/20
Introduction
DESCRIPTION LOGICS REASONING
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
Can Panadol be prescribed to a 3-year-old patient?
- Is X satisfiable?DL reasoning tasks:
Check satisfiability of a concept (O |= X v ⊥)Check satisfiability of an ontology (O |= ⊥ )Check subsumption (O |= A v B)Classification (compute all A v B such that O |= A v B) more general than all tasks above
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 6/20
Introduction
DESCRIPTION LOGICS REASONING
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X ≡ Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Can Panadol be prescribed to a 3-year-old patient?- Is X satisfiable?
DL reasoning tasks:Check satisfiability of a concept (O |= X v ⊥)Check satisfiability of an ontology (O |= ⊥ )Check subsumption (O |= A v B)Classification (compute all A v B such that O |= A v B) more general than all tasks above
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 6/20
Introduction
DESCRIPTION LOGICS REASONING
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X ≡ Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Can Panadol be prescribed to a 3-year-old patient?- Is X satisfiable?DL reasoning tasks:
Check satisfiability of a concept (O |= X v ⊥)Check satisfiability of an ontology (O |= ⊥ )Check subsumption (O |= A v B)Classification (compute all A v B such that O |= A v B) more general than all tasks above
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 6/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?
EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,=
Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:uses u and ∃:
Panadol ≡ Drug u ∃contains.Paracetamolsuitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,=
EXAMPLE
A v ∃F.[< 2]∃F.[= 1] v B∃F.[= 0] v C
A v B t C
Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,= >,= <,> ≤,= ≥,= ≤,≥
Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,= >,= <,> ≤,= ≥,= ≤,≥Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype use
EL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,= >,= <,> ≤,= ≥,= ≤,≥Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype use
EL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,= >,= <,> ≤,= ≥,= ≤,≥Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equality
Absence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
EL AND DATATYPES
EL [Baader et al., IJCAI 2005] is a simple DL:
uses u and ∃:Panadol ≡ Drug u ∃contains.Paracetamol
suitable for large-scale ontologies such as SNOMED or GOreasoning in PTIME
EL with datatypes is EXPTIME-complete. Why?EL extended with disjunction is EXPTIME-complete anddisjunction is expressible using datatypes:
<,= >,= <,> ≤,= ≥,= ≤,≥Baader et al. [IJCAI 2005] ensure polynomiality byrestrictions on datatype useEL Profile of OWL 2 admits only equalityAbsence of inequalities reduces the utility of OWL 2 EL
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 7/20
Introduction
RESULTS OVERVIEW
Relax the restrictions on datatype use by allowinginequalities and remaining polynomial
Key ideaDistinguish negative (LHS of axiom) and positive (RHS ofaxiom) occurrences of datatypes
Main results
Full classification of cases where datatypes are used andtractability is preserved for N, Z, Q and R
Polynomial, sound and complete reasoning procedure forextensions of EL⊥ with restricted numerical datatypes
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 8/20
Introduction
RESULTS OVERVIEW
Relax the restrictions on datatype use by allowinginequalities and remaining polynomial
Key ideaDistinguish negative (LHS of axiom) and positive (RHS ofaxiom) occurrences of datatypes
Main results
Full classification of cases where datatypes are used andtractability is preserved for N, Z, Q and R
Polynomial, sound and complete reasoning procedure forextensions of EL⊥ with restricted numerical datatypes
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 8/20
Introduction
RESULTS OVERVIEW
Relax the restrictions on datatype use by allowinginequalities and remaining polynomial
Key ideaDistinguish negative (LHS of axiom) and positive (RHS ofaxiom) occurrences of datatypes
Main results
Full classification of cases where datatypes are used andtractability is preserved for N, Z, Q and R
Polynomial, sound and complete reasoning procedure forextensions of EL⊥ with restricted numerical datatypes
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 8/20
Introduction
RESULTS OVERVIEW
Relax the restrictions on datatype use by allowinginequalities and remaining polynomial
Key ideaDistinguish negative (LHS of axiom) and positive (RHS ofaxiom) occurrences of datatypes
Main results
Full classification of cases where datatypes are used andtractability is preserved for N, Z, Q and R
Polynomial, sound and complete reasoning procedure forextensions of EL⊥ with restricted numerical datatypes
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 8/20
Introduction
EL FAMILY OF DESCRIPTION LOGICS
The EL language:
Syntax SemanticsAtomic concept C C(x)Top > >Conjunction C u D C(x) ∧ D(x)Existential restriction ∃R.C ∃y : R(x, y) ∧ C(y)
EL⊥ with Numerical Datatypes
Bottom ⊥ ⊥Datatype restriction ∃F.range ∃v : F(x, v) ∧ v ∈ range
range = [< n] | [≤ n] | [> n] | [≥ n] | [= n] ⊆ D = N,Z,R,QAxioms
Concept inclusion C v D ∀x : C(x)→ D(x)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 9/20
Introduction
EL FAMILY OF DESCRIPTION LOGICS
The EL language:
Syntax SemanticsAtomic concept C C(x)Top > >Conjunction C u D C(x) ∧ D(x)Existential restriction ∃R.C ∃y : R(x, y) ∧ C(y)
EL⊥ with Numerical Datatypes
Bottom ⊥ ⊥Datatype restriction ∃F.range ∃v : F(x, v) ∧ v ∈ range
range = [< n] | [≤ n] | [> n] | [≥ n] | [= n] ⊆ D = N,Z,R,Q
Axioms
Concept inclusion C v D ∀x : C(x)→ D(x)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 9/20
Introduction
EL FAMILY OF DESCRIPTION LOGICS
The EL language:
Syntax SemanticsAtomic concept C C(x)Top > >Conjunction C u D C(x) ∧ D(x)Existential restriction ∃R.C ∃y : R(x, y) ∧ C(y)
EL⊥ with Numerical Datatypes
Bottom ⊥ ⊥Datatype restriction ∃F.range ∃v : F(x, v) ∧ v ∈ range
range = [< n] | [≤ n] | [> n] | [≥ n] | [= n] ⊆ D = N,Z,R,QAxioms
Concept inclusion C v D ∀x : C(x)→ D(x)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 9/20
Introduction
EL FAMILY OF DESCRIPTION LOGICS
The EL language:
Syntax SemanticsAtomic concept C C(x)Top > >Conjunction C u D C(x) ∧ D(x)Existential restriction ∃R.C ∃y : R(x, y) ∧ C(y)
EL⊥ with Numerical Datatypes
Bottom ⊥ ⊥Datatype restriction ∃F.range ∃v : F(x, v) ∧ v ∈ range
range = [< n] | [≤ n] | [> n] | [≥ n] | [= n] ⊆ D = N,Z,R,QAxioms
Concept inclusion C v D ∀x : C(x)→ D(x)
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 9/20
Reasoning in EL⊥(D)
OUTLINE
1 INTRODUCTION
2 REASONING IN EL⊥(D)
3 CONCLUSION
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 10/20
Reasoning in EL⊥(D)
ALGORITHM STAGES
1 Standard normalization of the axioms
Normal formsNF1 A v BNF2 A1 u A2 v BNF3 A v ∃R.BNF4 ∃R.B v ANF5 A v ∃F.rangeNF6 ∃F.range v A
2 Saturation of the axioms under inference rules, such as:
A v B A v CA v D
B u C v D ∈ O
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 11/20
Reasoning in EL⊥(D)
ALGORITHM STAGES
1 Standard normalization of the axioms
Normal formsNF1 A v BNF2 A1 u A2 v BNF3 A v ∃R.BNF4 ∃R.B v ANF5 A v ∃F.rangeNF6 ∃F.range v A
2 Saturation of the axioms under inference rules, such as:
A v B A v CA v D
B u C v D ∈ O
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 11/20
Reasoning in EL⊥(D)
REASONING RULES (PART I)
Rules from EL⊥
IR1A v A
IR2A v > CR1
A v BA v C
B v C ∈ O
CR2A v B A v C
A v DB u C v D ∈ O
CR3A v B
A v ∃R.CB v ∃R.C ∈ O
CR4A v ∃R.B B v C
A v D∃R.C v D ∈ O
CR5A v ∃R.B B v ⊥
A v ⊥
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 12/20
Reasoning in EL⊥(D)
REASONING RULES (PART II)
New rules for datatypes
A v ∃F.[< m]
A v B∃F.[< n] v B ∈ O, m ≤ n
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 13/20
Reasoning in EL⊥(D)
REASONING RULES (PART II)
New rules for datatypes
ID1A v ⊥
A v ∃F.[< 0] ∈ O
CD1A v B
A v ∃F.rangeB v ∃F.range ∈ O
CD2(<,<)A v ∃F.[< m]
A v B∃F.[< n] v B ∈ O, m ≤ n
CD2(=,<)A v ∃F.[= m]
A v B∃F.[< n] v B ∈ O, m < n
CD2(=,=)A v ∃F.[= m]
A v B∃F.[= n] v B ∈ O, m = n . . .
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 13/20
Reasoning in EL⊥(D)
THE EL⊥(D)ALGORITHM
The algorithm is:
sound: all rules derive logical consequences of premises
polynomial as only polynomially many axioms are possible
not complete in general (EL⊥(D) is EXPTIME-complete)
complete under certain restrictions on datatypes
What type of restrictions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 14/20
Reasoning in EL⊥(D)
THE EL⊥(D)ALGORITHM
The algorithm is:
sound: all rules derive logical consequences of premises
polynomial as only polynomially many axioms are possible
not complete in general (EL⊥(D) is EXPTIME-complete)
complete under certain restrictions on datatypes
What type of restrictions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 14/20
Reasoning in EL⊥(D)
THE EL⊥(D)ALGORITHM
The algorithm is:
sound: all rules derive logical consequences of premises
polynomial as only polynomially many axioms are possible
not complete in general (EL⊥(D) is EXPTIME-complete)
complete under certain restrictions on datatypes
What type of restrictions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 14/20
Reasoning in EL⊥(D)
THE EL⊥(D)ALGORITHM
The algorithm is:
sound: all rules derive logical consequences of premises
polynomial as only polynomially many axioms are possible
not complete in general (EL⊥(D) is EXPTIME-complete)
complete under certain restrictions on datatypes
What type of restrictions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 14/20
Reasoning in EL⊥(D)
THE EL⊥(D)ALGORITHM
The algorithm is:
sound: all rules derive logical consequences of premises
polynomial as only polynomially many axioms are possible
not complete in general (EL⊥(D) is EXPTIME-complete)
complete under certain restrictions on datatypes
What type of restrictions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 14/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR N
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Restrict positive and negative occurrences of datatyperelations so as disjunction is not expressible
All restrictions are maximal:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 15/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR N
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Restrict positive and negative occurrences of datatyperelations so as disjunction is not expressible
All restrictions are maximal:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 15/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR N
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Restrict positive and negative occurrences of datatyperelations so as disjunction is not expressible
All restrictions are maximal:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 15/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR N
Negative relations Positive relations<,≤, >,≥,= =
<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= >,≥,=
All restrictions are maximal:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 15/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR N
Negative relations Positive relations<,≤, >,≥,= =
<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= >,≥,=
All restrictions are maximal:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 15/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR N
Negative relations Positive relations<,≤, >,≥,= = ,<
<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= >,≥,=
All restrictions are maximal:
EXAMPLE
A v ∃F.[< 2]∃F.[= 1] v B∃F.[= 0] v C
A v B t C
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 15/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR ZNegative relations Positive relations
<,≤, >,≥,= == <,≤, >,≥,=
<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= >,≥,=>,≥,= <,≤,=
Additional datatype restrictions: integers do not have aminimal element such as 0.
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 16/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR ZNegative relations Positive relations
<,≤, >,≥,= == <,≤, >,≥,=
<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= >,≥,=>,≥,= <,≤,=
Additional datatype restrictions: integers do not have aminimal element such as 0.
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 16/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR ZNegative relations Positive relations
<,≤, >,≥,= == <,≤, >,≥,=
<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= >,≥,=>,≥,= <,≤,=
Additional datatype restrictions: integers do not have aminimal element such as 0.
EXAMPLE
A v ∃F.[< 2]∃F.[= 1] v B∃F.[= 0] v C
A 6v B t C
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 16/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR Q AND RNegative relations Positive relations
<,≤, >,≥,= =≤,= <,≤, >,≥,=≥,= <,≤, >,≥,=<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= <,>,≥,=>,≥,= <,≤, >,=
Between every two different numbers there exists a thirdone:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 17/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR Q AND RNegative relations Positive relations
<,≤, >,≥,= =≤,= <,≤, >,≥,=≥,= <,≤, >,≥,=<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= <,>,≥,=>,≥,= <,≤, >,=
Between every two different numbers there exists a thirdone:
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 17/20
Reasoning in EL⊥(D)
RESTRICTIONS FOR Q AND RNegative relations Positive relations
<,≤, >,≥,= =≤,= <,≤, >,≥,=≥,= <,≤, >,≥,=<,≤ <,≤, >,≥,=>,≥ <,≤, >,≥,=
<,≤,= <,>,≥,=>,≥,= <,≤, >,=
Between every two different numbers there exists a thirdone:
EXAMPLE
A v ∃F.[< 3]∃F.[= 2] v B∃F.[< 2] v C
A 6v B t C
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 17/20
Conclusion
OUTLINE
1 INTRODUCTION
2 REASONING IN EL⊥(D)
3 CONCLUSION
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 18/20
Conclusion
RESULTS OVERVIEWPolynomial, sound and complete reasoning procedure forextensions of EL⊥ with “safe” numerical datatypesFull classification of tractable cases for N, Z, Q and RCommon restriction for N, Z, Q and R:
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Candidate for an OWL 2 EL Profile extension
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 19/20
Conclusion
RESULTS OVERVIEWPolynomial, sound and complete reasoning procedure forextensions of EL⊥ with “safe” numerical datatypesFull classification of tractable cases for N, Z, Q and RCommon restriction for N, Z, Q and R:
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Candidate for an OWL 2 EL Profile extension
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 19/20
Conclusion
RESULTS OVERVIEWPolynomial, sound and complete reasoning procedure forextensions of EL⊥ with “safe” numerical datatypesFull classification of tractable cases for N, Z, Q and RCommon restriction for N, Z, Q and R:
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Candidate for an OWL 2 EL Profile extension
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 19/20
Conclusion
RESULTS OVERVIEWPolynomial, sound and complete reasoning procedure forextensions of EL⊥ with “safe” numerical datatypesFull classification of tractable cases for N, Z, Q and RCommon restriction for N, Z, Q and R:
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Candidate for an OWL 2 EL Profile extension
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 19/20
Conclusion
RESULTS OVERVIEWPolynomial, sound and complete reasoning procedure forextensions of EL⊥ with “safe” numerical datatypesFull classification of tractable cases for N, Z, Q and RCommon restriction for N, Z, Q and R:
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Candidate for an OWL 2 EL Profile extension
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 19/20
Conclusion
RESULTS OVERVIEWPolynomial, sound and complete reasoning procedure forextensions of EL⊥ with “safe” numerical datatypesFull classification of tractable cases for N, Z, Q and RCommon restriction for N, Z, Q and R:
Negative relations Positive relations<,≤, >,≥,= =
EXAMPLEPanadol v ∃contains.(Paracetamol u ∃mgPerTablet.[= 500])
Patient u ∃hasAge.[< 6] u ∃hasPrescription.∃contains.(Paracetamol u ∃mgPerTablet.[> 250]) v ⊥
X v Patient u ∃hasAge.[= 3] u ∃hasPrescription.Panadol
Candidate for an OWL 2 EL Profile extension
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 19/20
Conclusion
FUTURE WORK
Extend the reasoning algorithm:
complex role inclusionsfunctional data propertiesnominalsdomain and range restrictionsHorn SHIQ [Kazakov, IJCAI, 2009]
More fine-grained analysis by also considering which dataproperties are used with relations
Thank you for your attention! Questions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 20/20
Conclusion
FUTURE WORK
Extend the reasoning algorithm:complex role inclusionsfunctional data propertiesnominalsdomain and range restrictionsHorn SHIQ [Kazakov, IJCAI, 2009]
More fine-grained analysis by also considering which dataproperties are used with relations
Thank you for your attention! Questions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 20/20
Conclusion
FUTURE WORK
Extend the reasoning algorithm:complex role inclusionsfunctional data propertiesnominalsdomain and range restrictionsHorn SHIQ [Kazakov, IJCAI, 2009]
More fine-grained analysis by also considering which dataproperties are used with relations
Thank you for your attention! Questions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 20/20
Conclusion
FUTURE WORK
Extend the reasoning algorithm:complex role inclusionsfunctional data propertiesnominalsdomain and range restrictionsHorn SHIQ [Kazakov, IJCAI, 2009]
More fine-grained analysis by also considering which dataproperties are used with relations
Thank you for your attention! Questions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 20/20
Conclusion
FUTURE WORK
Extend the reasoning algorithm:complex role inclusionsfunctional data propertiesnominalsdomain and range restrictionsHorn SHIQ [Kazakov, IJCAI, 2009]
More fine-grained analysis by also considering which dataproperties are used with relations
Thank you for your attention! Questions?
Despoina Magka, Yevgeny Kazakov and Ian Horrocks Tractable Extensions of EL with Numerical Datatypes 20/20