reference context
Marco Rospocher <https://dkm.fbk.eu/rospocher>
### Semantic Classes and Roles The *PreMOn Ontology Core Module* extends *lemon* by introducing classes [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass) and [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole). [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass) homogeneously represents the semantic classes from the various predicate models. That is, individuals of this class correspond to rolesets in PB and NB (e.g., *pm:nb10-seller.01* and *pm:pb17-sell.01*), verb classes in VN (e.g., *pm:vn32-give-13.1-1*), and frames in FN (e.g., *pm:fn15-commerce sell*). An instance of [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass) typically has (via property [pmo:semRole](http://premon.fbk.eu/ontology/core#semRole)) a number of [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole)s, representing, from a semantic point of view, the roles the arguments of that [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass) can play. Semantic roles are defined locally to semantic classes, so VN *agent* is represented as multiple semantic roles, one for each verb class it occurs in, and with each semantic role linked to its specific selectional restrictions (if any). Note that [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass) is defined as subclass of [ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept), as we see [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass)es as essentially informal concepts rather than well defined concepts of a formal ontology (although an ontology can be derived from them, cf., FrameBase and ESO). In particular, being [ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept)s, [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass)es inherit the link to lexical entries. Properties [pmo:classRel](http://premon.fbk.eu/ontology/core#classRel) and [pmo:roleRel](http://premon.fbk.eu/ontology/core#roleRel), and their resource-specific subproperties, are introduced to express the relations between elements at each level, such as subtyping, and predicate and role inheritance (e.g., [pmofn:inheritsFrom](http://premon.fbk.eu/ontology/fn#inheritsFrom) and [pmofn:inheritsFromFER](http://premon.fbk.eu/ontology/fn#inheritsFromFER) for FN). Additional resource-specific classes (e.g., [pmovn:ThematicRole](http://premon.fbk.eu/ontology/vn#ThematicRole)) and properties (e.g., [pmovn:thematicRole](http://premon.fbk.eu/ontology/vn#thematicRole)) further characterize important aspects of each predicate model, like commonalities between semantic roles. ### Mappings Mappings between different predicate models are practically relevant but cannot be expressed using only the classes above, as they are often defined (e.g., in SemLink and PredicateMatrix) in terms of <[pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass), [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry)> pairs. To model these pairs, one could reuse the notion of ontolex:LexicalSense. However, its formalization in lemon as reified relation depends on the existence of (exactly) one ontological entity for each <[ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept), [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry)> pair, a strong constraint that we do not necessarily need for our purposes. Therefore, we introduce the [pmo:Conceptualization](http://premon.fbk.eu/ontology/core#Conceptualization) class. Structurally, a [pmo:Conceptualization](http://premon.fbk.eu/ontology/core#Conceptualization) can be seen as the reification of the [ontolex:evokes](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Evokes) relation between [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry) and [ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept). Semantically, it can be seen as a very specific intensional concept (among many, in case of polysemy) evoked by a single [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry), which can be generalized to a [ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept) when multiple entries are considered but with a possible loss of information that prevents precise alignments to be represented. Mappings are explicitly represented as individuals of class [pmo:Mapping](http://premon.fbk.eu/ontology/core#Mapping), and can be seen as sets of (or n-ary relations between) either (i) [pmo:Conceptualization](http://premon.fbk.eu/ontology/core#Conceptualization)s, (ii) [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass)es, and (iii) [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole)s, with role mappings anchored to conceptualization or class mappings via property [pmo:semRoleMapping](http://premon.fbk.eu/ontology/core#semRoleMapping). We rely on this set-like modeling, since mappings are not necessarily represented as binary relations in predicate mapping resources: e.g., in the PredicateMatrix, each row represents the mapping of a semantic role / lexical entry pair over the different resources (e.g., <*13.1-1-agent*, *deal*> in VN, <*sell.01-arg0*, *sell*> in PB, <*Commerce Sell-seller*, *sell*> in FN) as well as the corresponding WordNet verb sense. Reifying the n-ary mapping relation also allows us, if needed, to further characterize each single mapping, asserting additional information such as confidence and reliability. Moreover, it is possible to further specialize mappings (e.g., to model mappings holding only in one direction, from a resource to another one, or to represent different types of relationships among the members of the mapping) by subtyping the [pmo:Mapping](http://premon.fbk.eu/ontology/core#Mapping) class or the property (pmo:item) relating a [pmo:Mapping](http://premon.fbk.eu/ontology/core#Mapping) to its members. ### Ontological Mappings Building on *lemon*, *PreMOn* inherits the capability of linking lexical content to ontological resources. In particular, being [ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept)s, [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass)es inherit the link (via [ontolex:isConceptOf](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Concept)) to the ontological entities formalizing them, typically event classes. However, in order to properly align predicate models to existing frame/event-based ontologies such as FrameBase and ESO, *PreMOn* introduces the property [pmo:ontologyMatch](http://premon.fbk.eu/ontology/core#ontologyMatch), having as domain [skos:Concept](https://www.w3.org/2009/08/skos-reference/skos.html#Concept), to enable the possibility of linking to ontological entities also other resources than [ontolex:LexicalConcept](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Concept)s. In particular, [pmo:ontologyMatch](http://premon.fbk.eu/ontology/core#ontologyMatch) property enables the alignment to ontology elements of resources such as: * [pmo:Conceptualization](http://premon.fbk.eu/ontology/core#Conceptualization)s * [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass)es (in this case, [ontolex:isConceptOf](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Concept) can be seen as a subproperty of [pmo:ontologyMatch](http://premon.fbk.eu/ontology/core#ontologyMatch), although we abstained from formally enforcing this) * [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole)s. ### Annotations Predicate models are typically complemented by examples showing concrete occurrences of semantic classes and roles in text. More generally, a text can be annotated with semantic classes and roles as a result of manual or automatic SRL. The PreMOn Ontology provides some common primitives, based on the [NLP Interchange Format](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core/nif-core.html) (NIF) by Hellmann et al. (2013), which aim at properly modeling the heterogeneous annotations of a text for different predicate models. NIF introduces the general notion of [nif:String](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#String) to represent arbitrary text strings. [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context) is a particular subclass of [nif:String](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#String), representing a whole string of text. Any substring (itself a [nif:String](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#String)) has a [nif:referenceContext](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#referenceContext) relation to the [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context) individual representing the whole text containing it. To specifically model the aforementioned examples complementing predicate models, we introduce [pmo:Example](http://premon.fbk.eu/ontology/core#Example), subclass of [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context), to represent the string associated with the example. The occurrence of a [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry), [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass), or [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole) in a [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context) is denoted by an instance of [nif:Annotation](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Annotation), related to the given [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry), [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass), or [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole) via property [pmo:valueObj](http://premon.fbk.eu/ontology/core#valueObj) (the value attached to the annotation), and to the [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context) instance via property [nif:annotation](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#annotation). If detailed information on the specific span of text (i.e., substring) denoting the [ontolex:LexicalEntry](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification#Lexical_Entry), [pmo:SemanticClass](http://premon.fbk.eu/ontology/core#SemanticClass), or [pmo:SemanticRole](http://premon.fbk.eu/ontology/core#SemanticRole) is available (e.g., FN provides the specific offsets of lexical units, frames, and frame elements, in the example text) an additional instance of [pmo:Markable](http://premon.fbk.eu/ontology/core#Markable), subclass of [nif:String](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#String), is created and linked to the specific [nif:Annotation](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Annotation) and [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context) via properties [nif:annotation](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#annotation) and [nif:referenceContext](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#referenceContext), respectively. As the same [nif:Context](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Context) may contain multiple [nif:Annotation](http://persistence.uni-leipzig.org/nlp2rdf/ontologies/nif-core#Annotation)s referring to one or more semantic classes and their corresponding roles, an additional [pmo:AnnotationSet](http://premon.fbk.eu/ontology/core#AnnotationSet) instance is created to cluster annotations from the same predicate structure.
DKM, Fondazione Bruno Kessler <http://dkm.fbk.eu/>
Predicate Model for Ontologies (PreMOn) - Core ontology module
The [PreMOn Ontology](http://premon.fbk.eu) is an extension of [lemon](https://www.w3.org/community/ontolex/wiki/Final_Model_Specification) (W3C Ontology Lexicon Community Group, 2015) for representing *predicate models* and their *mappings*. The Core Module of the PreMOn Ontology defines the main abstractions for modelling *semantic classes* with their *semantic roles*, *mappings* between different predicate models, and *annotations*.
This ontology is licensed under CC-BY-SA <http://creativecommons.org/licenses/by-sa/4.0/>
semantic class relation
SemanticClass homogeneously represents the semantic classes from the various predicate models. That is, individuals of this class correspond to rolesets in PB and NB (e.g., pm:nb10-seller.01 and pm:pb17-sell.01), verb classes in VN (e.g., pm:vn32-give-13.1-1), and frames in FN (e.g., pm:fn15-commerce sell).
Semantic Class
evoked concept
Structurally, it can be seen as the reification of the ontolex:evokes relation between ontolex:LexicalEntry and ontolex:LexicalConcept. Semantically, it can be seen as a very specific intensional concept (among many, in case of polysemy) evoked by a single ontolex:LexicalEntry, which can be generalized to a ontolex:LexicalConcept when multiple entries are considered but with a possible loss of information that prevents precise alignments to be represented.
Conceptualization
evoking entry
first, item, next are used to model set-like construct
first
item
next
semantic role relation
SemanticRoles tepresent the roles the arguments of a SemanticClass can play. Semantic roles are defined locally to semantic classes, so VN agent is represented as multiple semantic roles, one for each verb class it occurs in, and with each semantic role linked to its specific selectional restrictions (if any).
Semantic Role
semantic role
relates a mapping between semantic roles to the corresponding mapping between semantic classes and/or conceptualizations
semantic role mapping
An individual of this class represents a mapping between SemanticRoles
Semantic Role Mapping
An individual of this class represents a mapping between Conceptualizations
Conceptualization Mapping
An individual of this class represents a mapping between SemanticClasses
Semantic Class Mapping
generic property to associate an object value to an instance
value
PreMOn generic property to associate a SKOS concept to an ontological entity
ontology (exact) match
abbreviation
generic property to associate an data value to an instance
Represent each annotation of a semantic class, togheter with its semantic roles, in an example
Annotation Set
An individual of this class represents a mapping between skos:Concepts
Mapping
Represent the text associated to an example
Example
Represent a piece of text to which some annotation is attached to
Markable