Week 5 Flashcards
Where does OWL stand for?
Ontology Web Language
A set or category of things having some property or attribute in common and differentiated rom others by kind, type or quality is called a…
class
In OWL, what is the superclass / subclass of everything called?
owl:Thing / owl:Nothing
A class for which all individuals can be listed is called…
enumerated class.
Assertion that an individual is a member of a class is called…
classification.
Another word for classification, in terms of relationship is…
class inclusion
A feature, or characterstic of an individual is called a…
property
In OWL, properties define…
relationships.
In OWL, properties have direction. True / False
True (artist creates artwork). subject –> left hand side; object –> right hand side.
Class of allowed “values” at the left side, origin of the relationship is called…
domain
Class of allowed “values” at the right side, destination of the relationship is called…
range.
What is the extensional view of classes?
Classes are equal if and only if they have the same class extension
What is class extension?
The set of members in a class
Give an example of a class expression.
mother = woman and parent
A constraint which must be true for class membership, but is not enough to classify it as a member of the class is called…
a necessary (class) definition.
A definition which allows us to classify an individual as a member of a class is called…
a sufficient class definition.
Whenever each object in a categorisation structure participates in at least one subclass, the generalisation is deemed…
complete.
Whenever an object participates in only ONE single subclass, the generalisation is deemed…
disjoint.
Three classes of vertical organization are…
basic-level classes (middle layer in hierarchies), upper-level classes (abstract level classes that organize the hierarchy), lower-level classes (domain specific cases)
In horizontal organization, the categories are at the same…
level of abstraction, emphasis lies on commonalities within a category, rather than on differences with other categories.
Instances of a class more typical than the other instances are called…
prototypes.
