from-negatives-to-knowledge

🧠 Hands-On Activities

Activity 1. Entity Annotation

Look at this sample image from the Marie and James B. McMillan Photograph Collection (PH-00334).

👀 Who can you identify?

🗂 Part B: Mapping Concepts to Classes

Now that you’ve reviewed the caption, let’s examine how key entities in the photo can be represented using Schema.org classes.

Prompt: Read the caption and explore how each of the following Schema.org classes applies to people, groups, organizations, and places mentioned.

Click each class below to reveal the corresponding values:

schema:Person

Dr. James B. McMillan
Dr. Charles I. West
Sammy Davis, Jr.
Mons. James B. Empey

schema:PerformingGroup

Will Mastin Trio

schema:Organization

George Washington Carver Memorial Institute
St. Joan of Arc Catholic Church

schema:Place

Sands Hotel and Casino (3355 Las Vegas Boulevard South)

schema:CatholicChurch

St. Joan of Arc Catholic Church

❓ Part B: Reflective Questions

Why do you think St. Joan of Arc Catholic Church appears under both schema:Organization and schema:CatholicChurch?

What different aspects of the church do these two classes represent?

Now try searching for the Clark County Nevada version of St. Joan of Arc Catholic Church on Wikidata. Do you see more than one result?

What are the differences between them — and how do the instance of (wdt:P31) values help you interpret whether you’re looking at a building or a congregation?

💡 Try this:
Using Part B: Mapping Concepts to Classes as a reference, complete the RDF triple statement by replacing the square brackets with an schema.org class.

Bonus challenge: Can you strengthen the connection between your Schema.org entity and its counterpart in Wikidata? Add a triple to your statement using the Wikidata Q-number for the matching item and the property skos:closeMatch.

Activity 2. Modeling Scenario and Writing RDF

Understanding how to express structured metadata in RDF is key to building your knowledge graph. Below is an example using real entities from the project.

📄 RDF Triple Structure in Turtle Syntax

@prefix schema: <http://schema.org/> .
@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
@prefix agrelon: <https://d-nb.info/standards/elementset/agrelon#> .
@prefix unl: <https://special.library.unlv.edu/taxonomy/term/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

unl:16527 a skos:Concept ;
    a schema:Person ;
    skos:prefLabel "West, Charles I., 1908-1984"@en ;
    skos:note "American doctor, civil rights activist, and newspaper publisher."@en ;
    skos:inScheme unl: ;
    schema:name "Charles I. West"@en ;
    schema:givenName "Charles"@en ;
    schema:additionalName "I."@en ;
    schema:familyName "West"@en ;
    schema:birthDate "1908-09-27"^^xsd:date ;    
    schema:birthPlace <https://sws.geonames.org/4138106/> ;
    schema:deathDate "1984-10"^^xsd:date ;
    schema:deathPlace <https://sws.geonames.org/7174241/> ;
    schema:hasOccupation <http://id.loc.gov/authorities/subjects/sh85026385> ;
    schema:hasOccupation <http://id.loc.gov/authorities/subjects/sh85101610> ;
    schema:alumniOf unl:26371 ;
    schema:alumniOf unl:26372 ;
    schema:founder unl:13280 ;
    agrelon:HasSpouse unl:27781 ;
    agrelon:hasChild unl:17559 ;
    agrelon:HasColleague unl:15502 ;
    agrelon:HasColleague unl:15811 ;
    agrelon:HasColleague unl:16510 ;
    agrelon:HasColleague unl:1758 ;
    agrelon:HasColleague unl:17776 ;
    agrelon:HasColleague unl:6025 ;
    skos:exactMatch <http://id.loc.gov/authorities/names/no2019080699> ;
    skos:closeMatch <http://www.wikidata.org/entity/Q105758712> ;
    rdfs:seeAlso <http://n2t.net/ark:/62930/f13t22> .

This example uses Schema.org, SKOS, and Agrelon vocabularies to model relationships and biographical metadata. The unl: prefix represents local identifiers from the UNLV taxonomy.

🧾 Explanation of RDF Predicates and Selected Triple Components

Triple Component	Description
`a skos:Concept`	Declares the resource as a SKOS concept, allowing it to function in a controlled vocabulary or thesaurus.
`a schema:Person`	Declares the resource as a person class using Schema.org.
`skos:prefLabel`	The preferred label or name of the person, formatted for use in SKOS vocabularies.
`skos:note`	A brief biographical note or description.
`skos:inScheme unl:`	Indicates this term belongs to the UNLV controlled vocabulary.
`schema:name`	The name of the item (in direct order), combining given, middle, and family names.
`schema:givenName`	The person’s first name.
`schema:additionalName`	The person’s middle name or initial.
`schema:familyName`	The person’s last name or family name.
`schema:birthDate`	The person’s birthdate in ISO format using the XML Schema datatype.
`schema:birthPlace`	URI referring to the person’s place of birth.
`schema:deathDate`	The person’s deathdate in ISO format using the XML Schema datatype.
`schema:deathPlace`	URI referring to the person’s place of death.
`schema:hasOccupation`	Links to one or more occupation terms using controlled subject vocabularies (e.g., LCSH).
`schema:alumniOf`	Indicates the person attended (graduated from) the institution identified by the URI.
`schema:founder`	Indicates the person founded the organization or entity identified by the URI.
`agrelon:HasSpouse unl:27781`	Relationship link to a spouse entity.
`agrelon:hasChild unl:17559`	Relationship link to a child entity.
`agrelon:HasColleague`	Indicates professional relationships with identified colleagues.
`skos:exactMatch`	Links to a matching external authority record (e.g., Library of Congress).
`skos:closeMatch`	Links to a closely matching external authority record (e.g., Wikidata, Dbpedia).
`rdfs:seeAlso`	Further information about the subject resource, typically linking to related web or archival content.

💡 Part B: Building on Classes from Activity 1

Using the example URIs and classes below, write RDF statements to describe each entity. For each one:

Use the a keyword to assign the appropriate schema: class as its rdf:type
Add an skos:prefLabel to provide a human-readable name
Add a skos:note to briefly describe the entity

Entity	URI	Class (click on Class to explore their properties)
Sammy Davis, Jr.	https://special.library.unlv.edu/taxonomy/term/3454	`schema:Person`
Will Mastin Trio	https://special.library.unlv.edu/taxonomy/term/9834	`schema:PerformingGroup`
Mons. James B. Empey	https://special.library.unlv.edu/taxonomy/term/28078	`schema:Person`
St. Joan of Arc Catholic Church	https://special.library.unlv.edu/taxonomy/term/28100	`schema:Organization`
Sands Hotel & Casino	https://special.library.unlv.edu/taxonomy/term/11258	`schema:Place`

💡 Try This: Use the following entities to write your own RDF triples (SEE OUR PROJECT CLASS & PROPERTY DOCUMENTATION):

unl:13280 Las Vegas voice

unl:17776 Clinton Wright

unl:27746 Arkansas Agricultural, Mechanical, and Normal College

unl:16527 Dr. Charles I. West

Focus on:

Assigning the correct class using a (short for rdf:type)
Using skos:prefLabel and schema:name for the labels
Using skos:note for a description
Describing relationships using properties like schema:memberOf, schema:member, schema:alumniOf, schema:alumni, agrelon:hasEmployer, agrelon:hasEmployee, or schema:affiliation
Linking entities to external name authority files via skos:closeMatch or skos:exactMatch

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