COMP62342 Using Ontologies Sean Bechhofer - - PowerPoint PPT Presentation
COMP62342 Using Ontologies Sean Bechhofer sean.bechhofer@manchester.ac.uk Uli Sattler ulrike.sattler@manchester.ac.uk Today SKOS Linked Data Some clarifications of misunderstandings I saw in your essays More on Profiles
Sean Bechhofer sean.bechhofer@manchester.ac.uk Uli Sattler ulrike.sattler@manchester.ac.uk
✓ SKOS ✓ Linked Data
– for MCQ generation – in an information system
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Furniture SubClassOf hasShape exactly 1 Shape ?
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Class: ¡Square ¡SubClassOf ¡Shape Class: ¡Circle ¡SubClassOf ¡Shape Class: ¡Rectangle ¡SubClassOf ¡Shape ¡ DisjointClasses: ¡Square, ¡Circle, ¡Rectangle ¡ Class: ¡Shape ¡SubClassOf ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡(Square ¡or ¡Circle ¡or ¡Rectangle) Property ¡hasShape ¡Range: ¡Shape ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡Domain: ¡Furniture ¡ Class: ¡Furniture ¡SubClassOf ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡hasShape ¡some ¡Shape ¡ Class: ¡Chair ¡SubClassOf ¡Furniture ¡and ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡hasShape ¡only ¡Rectangle ¡
– your lungs and your chest? – a bed and its bedroom – an apple and its tree
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Expressivity (Representational Adequacy) Usability (Weak Cognitive Adequacy vs. Cognitive Complexity) Computability (vs. Computational and Implementational Complexity)
class forming operators and axiom types – full Booleans
§ and, or, not
– Property Restrictions
§ some, only, min, max, exact
– Enumerations
§ Explicit classes formed from individuals
– Subclass and Equivalence – Property – Hierarchies – Chains – Characteristics: functional, inverse
– Do we always need all this expressivity?
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expressive power for efficiency of reasoning
OWL Profiles Recommendation http://www.w3.org/TR/owl2-profiles/
i.e., weakening any restriction results in increased computational complexity
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(a reasoner may infer something!)
#Document_Information_and_Annotations
Remember from last week:
S
w h a t t
i t h t h e s e d
u m e n t s /
t
i e s ?
– ontology captures rich domain knowledge – assessment/MCQ generation is costly & relevant – in particular for healthcare & medicine
e.g., control difficulty
Which of these is not a mammal?
MCQ Options Stem Key Distractors Follows a template: Stem: Which of these is not a (Class) X? Distractors: Y with O ⊨ Y ⊑ X Key: Y with O ⊭ Y ⊑ X
Template( 1( MCQ$ 1$ Template( 2(
MCQ$bank$
MCQ$5$ (Master)$ Stem$ Key$ D1$ D2$ D3$ $
Key( Less(plausible(distractor( Non(plausible(distractor(
MCQ$generator$
Plausible(distractor( Knowledge$source$
(( (( (( (( (( ((MCQ 2$ MCQ 3$ MCQ 4$ MCQ 6$ MCQ 7$ MCQ 8$
Template$library$
Template$1:$What$is$X?$ Template$2:$Which$is$odd?$ $ $ MCQ$ 5$ Stem$ Key$ D1$ D2$ D3$
$
Stem$ Key$ D4$ D5$ D6$
$
Ontology
OWL Reasoner OWL Reasoner
Ontology-Based MCQ Generator
The more similar D is to K, the more difficult is Q.
Which of these is not a mammal?
(Why) Is Whale more similar to Tuna than Giraffe? How to measure similarity of classes in ontologies?
– relational database – no-SQL database – files – XML docs – … – Ontology
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Which?
– recorded in different systems with possibly different structures – recorded by different clinicians with different styles
– many complex queries that need to change with changes in medicin
Patient Data
Healthcare Record Name: Bob History: Demographic:Smoker Sex: Male Endocardities 1998
Patient Documentation System User Interface
– those who have a known child – those described as Mother or Father – those described as Grandmother or Grandfather – …
Patient Data
Healthcare Record Name: Bob History: Demographic:Smoker Sex: Male Endocardities 1998
Patient Documentation System User Interface
TBox
Parent ≣ Person and hasChild some Person Mother ≣ Parent and Female Grandparent ≣ Parent and hasChild some Parent …
ABox
Healthcare Record Name: Bob History: Demographic: Smoker Sex: Male Endocardities 1998
Patient Doc. System
– use suitable TBox and – retrieve all those who are entailed to be an instance of Parent – …
User Interface
– background knowledge & terminology into ontology – data into DB or ABox
– behaviour into program code
TBox
Endocarditis = Inflammation and locatedIn Heart Inflammation = Disease and causedBy Bacteria
ABox
Healthcare Record Name: Bob History: Demographic: Smoker Sex: Male Endocardities 1998
Patient Doc. System User Interface
updated ontology
TBox
Endocarditis =
ABox
Healthcare Record
PDS UI
– where knowledge changes
– furniture – restaurants & food properties: allergies, ethical,… – biochemistry – defence, intelligence – (nano) engineering – recruitment/skills management
TBox
Table = Furniture and
ABox
…
PDS UI OWL API Reas
– e.g., NCI Thesaurus
TBox
Endocarditis = Inflammation and locatedIn some Heart Inflammation = Disease and causedBy some Bacteria
PDS UI OWL API Reas
TBox
Endocarditis =
ABox
Healthcare Record
PDS UI OWL API Reas
We tried to give you knowledge & understanding to answer these questions
– originally led by Alan Rector
– given the information about patient we have so far – what should we ask/document next?
– behaviour depends on but differs from – static knowledge captured in ontology
TBox
Endocarditis =
ABox
Healthcare Record
PDS UI OWL API Reas
– if your usage scenario doesn’t fit reasoner performance, consider
– entailment explanation (see Protégé’s “?”) – modularity (in OWL API tools!) – similarity (see MCQ generation)
– who’s building/maintaining the ontology? – who’s writing the code?
– many OWL tools around, but few stable/commercial
– Why do this?
– What do we model?
– How to represent things (in OWL)?
– Models, entailments, tableau – What exactly is it we are saying and what are the consequences?
– Using ontologies in applications.
– An alternative to OWL using OWL
– Using OWL or RDF(S) for data on the Web
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– Submit your report (individual) Thursday, May 17 (65% of CT mark) – Submit your ontology (group) Monday, May 14 – Peer assess your ontologies, Thursday, May 17 (35% of CT mark)
– use the OWL API to query an ontology – Monday, May 14
– a short essay – Monday, May 14
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answer competency questions like – Which pieces of furniture are found in the greatest number of rooms? – Which items of furniture are available in different sizes? – What are those sizes? – …see BB for more CQs: we’ve added some more!
model
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