Exam P11 Flashcards
What is the primary problem in knowledge sharing that ontologies aim to address
Ontologies aim to address the lack of a shared vocabulary and domain knowledge, specifically the use of the different terminology to refer the same concept, or the same terminology to refer different concepts
What are the three main elements that constitute an ontology? How do these elements help in restricting the interpretation of symbols?
The 3 elements that constitute an ontology are: hierarchies, axioms, and the specification of meaning.
- Hierarchy provides a structure a relation between concepts, offering context
- Axioms express constraints the symbols must comply with, relating them to other symbolism the ontology and limiting possible interpretations
- Specification of meaning directly address ambiguity by defining the intended understanding of each concept
Why is it stated that there is no single “The Ontology!” (from a non-philosophical perspective)? What factors can lead to different ontologies for the same domain?
There are several ways of organising concepts, and several facts can lead to different ontologies for the same domain:
- Different tasks the application the ontology has to preform
- Concepts being defined with different levels of detail
- Capturing different viewpoints of the same concept
- Using different granularity levels in conceptualisation
What are the three main types of ontologies discussed? Provide a brief description and an example for each type. Where did the Central Dogma ontology originate, and what is its purpose?
Representation Ontologies
Capture the representation primitives used to formalise knowledge in a given knowledge representation family or system
General or upper-level ontologies
Classify very general notions that are independent of a particular problem or domain and are applicable across domains
Domain ontologies
Are more specific and describe the vocabulary related to a particular domain. They provide vocabularies about concepts in the domain and relations between them
What is the general process involved in building ontologies? What are the main phases of the ontology development life cycle presented?
The process of building ontologies follows a life cycle. The main phases are: specification, conceptualisation, formalisation, implementation, and maintenance
What are some of the techniques for knowledge acquisition, conceptualization, and formalization?
Knowledge Acquisition
- Interviews with domain experts
- Text analyses of relevant documents
- Relevant bibliography, experts, books, norms, etc
Conceptualisation
- Mind maps
- Grouping concepts
- Developing a glossary of terms
- Create concept classification trees
Formalisation
- Defining concepts through axioms
- Organising concepts hierarchically
Why is it important to guarantee the quality of ontologies? What are the two main types of ontology evaluation mentioned, and what does each assess?
Flaws in the ontology can lead to misunderstandings, inconsistencies, and decrease the effectiveness of knowledge bases. The two main evaluations are:
- Technical evaluation, judges the intrinsic quality of the ontology itself. It assesses aspects such as consistency, completeness, and conciseness
- User assessment, judges the quality of the ontology from the perspective of its users. It assesses aspects such as usability and usefulness
