RDFS - Chapter 4 Interactive Companion

🌳 Class Hierarchy Explorer

Load a class hierarchy, then run inference to see all derived triples from rdfs:subClassOf and rdf:type.

// Select an example above

👆 Select an example, then click "Run Inference"

📚 Remember: rdfs:subClassOf is transitive and reflexive. Instances inherit all superclass types.

⚡ RDFS Inference Engine

Add RDFS triples and watch the engine derive new facts. Implements rules rdfs2, rdfs3, rdfs5, rdfs7, rdfs9, rdfs11.

Add triples above and click "Compute All Inferences"

🎯 Domain & Range Lab

Experiment with domain and range. See how they INFER types, not validate!

📐 Define Property Constraints

Property name: rdfs:domain (subject type): rdfs:range (object type):

📝 Use the Property

Subject: Object:

⚠️ RDFS infers types — it does NOT validate!

Explicit Triples:

ex:teaches rdfs:domain ex:Professor . ex:teaches rdfs:range ex:Course . ex:Alice ex:teaches ex:WebData .

✨ Inferred Triples:

ex:Alice rdf:type ex:Professor . # from rdfs:domain (rdfs2) ex:WebData rdf:type ex:Course . # from rdfs:range (rdfs3)

💡 Try This: Set domain to "ex:Professor" and subject to "ex:Fido". RDFS will happily infer Fido is a Professor — it doesn't reject it! For validation, use SHACL or ShEx.

🏗️ RDFS Vocabulary Builder

Build a complete RDFS vocabulary interactively and see the generated Turtle.

Generated Turtle:

@prefix ex: <http://example.org/> . @prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . # Add classes and properties above!

🎮 Inference Challenge

Given an RDFS graph, find ALL inferred triples. Type them to score points!

Score: 0

Challenge 1 / 3

Press "Start" to begin the challenge!

📝 Chapter 4 Quiz

Test your understanding of RDFS concepts!

📋 RDFS Cheat Sheet

Your quick reference for all things RDFS.

🏷️ RDFS Classes

rdfs:Resource    # Class of everything
rdfs:Class       # Class of all classes
rdfs:Literal     # Class of literal values
rdfs:Datatype    # Class of datatypes
rdfs:Container   # Superclass of Bag/Seq/Alt
rdf:Property     # Class of all properties

🔗 RDFS Properties

rdfs:subClassOf      # Class hierarchy
rdfs:subPropertyOf   # Property hierarchy
rdfs:domain          # Subject type (infers!)
rdfs:range           # Object type (infers!)
rdfs:label           # Human-readable name
rdfs:comment         # Human description
rdfs:seeAlso         # Related resource
rdfs:isDefinedBy     # Defining vocabulary

⚡ Key Inference Rules

rdfs2 (Domain): P domain C · X P Y → X type C

rdfs3 (Range): P range C · X P Y → Y type C

rdfs7 (SubProp): P subPropOf Q · X P Y → X Q Y

rdfs9 (SubClass): C subClassOf D · X type C → X type D

rdfs5 (Trans SubProp): P sub Q · Q sub R → P sub R

rdfs11 (Trans SubClass): C sub D · D sub E → C sub E

⚠️ Common Traps

❌ Domain/range do NOT validate — they INFER types

❌ Multiple domains = intersection (AND), not union

❌ rdfs:Class is an instance of itself (that's OK!)

✅ subClassOf is transitive AND reflexive

✅ For validation, use SHACL or ShEx instead

📄 Example Vocabulary

@prefix ex: <http://example.org/> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

ex:Person a rdfs:Class ;
  rdfs:label "Person"@en .

ex:Student rdfs:subClassOf ex:Person .

ex:enrolledIn a rdf:Property ;
  rdfs:domain ex:Student ;
  rdfs:range  ex:Course .

🔗 Useful Resources

🛠️ RDF Playground

Validate and visualize RDF

🔍 Wikidata Query Service

Query real RDFS data with SPARQL

📄 RDFS 1.1 Specification

Official W3C standard

📄 RDF 1.1 Semantics

Formal model-theoretic semantics