Son of SN

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Son of SN

• Barry Smith

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The Virtues of Single Inheritance ( True
Hierarchy)
better coding clearer instructions better
automatic reasoning better definitions
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Better codingShortfalls from single inheritance

• are often clues to bad coding, since they mark
  deviations from is_a relations which also block
  ontology alignment
• e.g. because is_a is no longer transitive
• because is_a is allowed to mean several
  different things
• Cf. Gene Ontology

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Use of multiple inheritance

• involves the assignment to the is_a relation of
  a plurality of different meanings within a single
  ontology.
• The resultant mélange makes coherent integration
  across ontologies achievable (at best) only under
  the guidance of human beings with relevant
  biological knowledge

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Is_a Overloading

• The success of ontology alignment depends
  crucially on the degree to which basic
  ontological relations such as is a can be relied
  on as having the same meanings in the different
  ontologies to be aligned.

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SN is not really a hierarchy

• because SNs is_a tail, the Metathesaurus, brings
  multiple inheritance
• e.g. regarding every chemical in Meta
• is_a chemical viewed structurally
• and
• is_a chemical viewed functionally

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Here again the presence of such Meta-induced
multiple inheritance

• is a clue to potential coding errors/suspicious
  terms in the SN
• e.g. Finding
• Environmental Effect of Humans

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Better definitions

• No circularity therefore declare primitives
• Necessary and sufficient conditions (definitions
  should have the form
• x is an instance of A def
• x is an instance of As parent term, the genus
  which B the differentia
• Intelligibility
• Substitutability

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UMLS-SN Semantic Relations

• Semantic Relation developmental_form_ofTUI
  T179Definition An earlier stage in the
  individual maturation of.
• satisfies substitutability

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UMLS-SN Semantic Relations

• Semantic Relation causesTUI T147Definition
  Brings about a condition or an effect.

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Oliviers goals

• Semantic types
• rename some types
• extract explicit classificatory principles
• rearrange hierarchy as needed
• revisit roles (place under sortals when unique)