# Wikidata Support in the Creation of Rich Semantic Metadata for Historical Archives
## 3 Mapping from the Wikidata Semantic Model to HERO
### Mappings between Properties and Mappings Between Complex Patterns
Given the Wikidata description shown in Figure 8, the application of the mappings prescribes to enrich the PRiSMHA Semantic KB by:  
* Stating that [PERSON] is affiliated to Politecnico di Torino (_<[PERSON]_, _isAffiliatedTo_, _Polito_>);
* Creating an instance of the _Profession_ HERO class, _professorAtPolito_, to represent the specific role played, i.e., \"professor at Politecnico di Torino\" (_<professorAtPolito_, _rdf:type_, _Professor_>);
* Stating that [PERSON] played the role of professorAtPolito (_<[PERSON]_, _isClassifiedBy_, professorAtPolito_);
* Stating that the role _professorAtPolito_ is institutionalized by the Politecnico di Torino (_<Polito_, _institutionalizes_, _professorAtPolito_>);
* Stating that the _professorAtPolito_ role is a sub-role of the _professor_ role (_<professorAtPolito_, _subRoleOf_, _professor_>); in fact, since the Wikidata _professor_ (Q121594) category is mapped to the _professor_ HERO role (i.e., _Map-c(Q121594) = professor_), in this case, _professor_ is an instance of the _Role_ HERO class; thus, the conditions expressed in mapping 3 (Table 3) are satisfied;
* Creating an instance of the _TemporaryAffiliationToOrganization_ HERO class, _ta_, to represent the fact that [PERSON] was temporarily affiliated to the Politecnico di Torino (_<ta_, _rdf:type_, _TemporaryAffiliationToOrganization_>);
* Stating that [PERSON] was temporarily affiliated to some organization (_<ta_, _hasAffiliationToOrganizationEntityElement_, _[PERSON]_>);
* Stating that the organization [PERSON] was temporarily affiliated to was the Politecnico of Torino (_<ta_, _hasAffiliationToOrganizationOrganizationElement_, _Polito_>);
* Stating that the temporary affiliation lasted for a specific time interval _temp_ (_<ta_, _hasTemporalParameterElement_, _temp>_);  
Figure 8: An example showing the use of qualifiers to represent additional information about a specific statement in Wikidata (from [[https://www.wikidata.org/wiki/Q286469](https://www.wikidata.org/wiki/Q286469)]([https://www.wikidata.org/wiki/Q286469](https://www.wikidata.org/wiki/Q286469)), accessed on 10 May 2021). * Creating an instance \(tc\) of the _TemporaryClassification_ HERO class, to represent the fact that [PERSON] temporarily played the role of professor at Politecnico di Torino (_<tc, rdf:type,TemporaryClassification>_);
* Stating that [PERSON] has temporarily played some role (_<tc, hasClassification-ClassifiedEntityElement_, _[PERSON]_);
* Stating that the role temporarily played by [PERSON] is _professorAtPolito_ (_<tc, hasClassificationClassifyingConceptElement_, _professorAtPolito>_);
* Stating that the temporary classification lasted for the _temp_ time interval (_<tc, hasTemporalParameterElement_, _temp>_);
* Stating that _temp_ is an instance of the _TimelInterval_ HERO class (_<temp rdf:type TimelInterval>_);
* Stating that _temp_ starts in 1974 (_<temp, intBeginsIn_, 1974>_);
* Stating _temp_ ends in 1977 (_<temp, intEndsIn_, 1977>_). In some cases, we defined complex mappings from Wikidata description patterns to event representations in HERO. For instance, Figure 9 shows a Wikidata statement, involving the _killed by_ Wikidata property (P157), asserting that [PERSON] (an Italian magistrate murdered by the Mafia) was assassinated by [PERSON], an Italian magioso (among other killers). In such cases, the Wikidata descriptions are translated by explicitly introducing HERO events (see mapping 4 in Table 3). In our example, the system suggests adding two events: (i) a homicide, perpetrated by [PERSON] (among the others) with [PERSON] as a victim, and (ii) the death of [PERSON], which was caused by the homicide. The choice of suggesting both events (the homicide and the death) is the result of our analysis of the intended semantics of the Wikidata property _killed by_: The use of such a property, in fact, implies that the subject died as a consequence of a homicide.