Relations

ConceptNet 5, unlike previous versions, has an open domain of relations. This allows us to express all kinds of useful information, but creates a new issue with data sparsity. Many of our sources give us very similar relations using different terminology.

Interlingual relations

ConceptNet has a set of interlingual relations. Their URIs start with /relation, and per tradition they are given a descriptive name in CamelCased English text, unless there's a compelling RDF name to use. These relations are presumed to be able to apply to concepts in many languages.

• /relation/IsA: the hypernym relation. When something is an arg1, it is an arg2.
  • /relation/InstanceOf: arg1 is a single instance of arg2. We consider this a subtype of IsA, and we also align it with the Semantic Web relation rdf:type.
• /relation/PartOf: arg1 is, or can be, an integral part of arg2.
• /relation/DirectObjectOf: A lexical relationship, specifying that arg1 can be the object of the verb arg2.
  • Often implies other semantic relationships, but this is the job of a learning rule to discover.
  • Indirect objects are more fiddly and language specific: /concept/en/to would be an example of where to find indirect objects.
• /relation/SubjectOf: A lexical relationship, specifying that arg1 can be the subject of the verb arg2.
• /relation/HasProperty: arg2 describes a property that arg1 has.
• /relation/HasPrerequisite: In order to do arg1, you need arg2.
• /relation/TranslationOf: arg1 and arg2 are words in different languages that often refer to the same concept. (Particularly useful if word senses are involved.)

Concepts are relations

In addition to interlingual relations, a concept in any language can be used as a relation.

Some of these are prepositions: /concept/en/in expresses that a possible location of arg1 is "in" arg2. Many preposition relations are more specific versions of /relation/AtLocation.

Others are phrases containing a verb, modifiers, and possibly a preposition. ReVerb is designed to extract these. Examples:

• /concept/en/be_city_in
• /concept/en/be_different_from
• /concept/en/also_speaks

Relations that should be connected

• /concept/en/be_part_of and /relation/PartOf
• /concept/en/be_different_from (from ReVerb) and /concept/en/be_not (from Verbosity)
• Anything with an adverb that doesn't change its polarity:
  • /concept/en/be_recently_acquire_by can become /concept/en/be_acquire_by, as an example