How to Do Things with Triples

WeST – Web Science & TechnologiesUniversity of Koblenz ▪ Landau, Germany

How to do things with triples?

Steffen Staab

Steffen [email protected]

WeST – Web Science & Technologies

What is a triple?

http://dbtune.org/musicbrainz/resource/artist/d87e52c5-bb8d-4da8-b941-9f4928627dc8

ABBA

foaf:name



What is Linked Data? The LOD Cloud



What is Linked Data? Linked Data Principles1. URIs as identifiers

2. http lookup

3. RDF (triples)

4. relations, also to other locations



What is Linked Data good for?

Data integration is easy Migrating different data sources to linked data is (relatively)

easy

Serendipitous use Discover new information by following data links

Data repurposing Querying and aggregating data can give new insights

...



Issue: From Data to Understanding

?



LENA – A Fresnel application

Fresnel Vocab by [Pietriga et al. ISWC-2006]



State-of-the-Art: One App at a Time

Shameless self-promotion: Semaplorer

[Schenk et al., JoWS 2009]

Billion Triples Challenge 1. Prize 2008



State-of-the-Art: One App at a Time

Shameless self-promotion: LISA

1. PrizeGerman Linked Open Gov Data Competition 2012



What‘s between the two?

One App at a Time

+ Great to use

+ Like DB application- Brittle- Not really extensible

Generic Frameworks

+ Can be applied on all data- Data remains hard to

understand- No process support- Noone wants to use them

?



PRAGMATICSWhat may be a theory for doing things with triples?



Austin: How to do things with words

Core Hypothesis by Austin:Speech is not only passively describing a given reality, but it can change the (social) reality it is describing through speech acts

Summary from Wikipedia, 2012-06-09



Why Do We Understand the Text Web?




Phonic act / graphic act:

T h e t e m p e r a t u r e i n M i l w a u k e e i s 1 0 0 ° F .

Locutionary act:

temperature(Milwaukee,100)Grice‘s maxims



Grice‘s Maxims / Cooperative Principle

Interacting agents mutually assume that: Quantity:

Be as informative as you possibly can, give as much information as needed, not more.

Quality: Be truthful

Pertinence: be relevant, say things pertinent to the discussion

Manner: be clear, brief, orderly as one can avoid obscurity and ambiguity

Criteria are competing and

overlapping.





T h e t e m p e r a t u r e i n M i l w a u k e e i s 1 0 0 ° F .

Locutionary act:

temperature(Milwaukee,100)

Illocutionary act:

Warn the conference attendees

Perlocutionary act:

Attendees stay in the shadow, etc…

Grice‘s maxims




Core Hypothesis by Austin:Speech is not only passively describing a given reality, but it can change the (social) reality it is describing through speech acts

Summary from Wikipedia, 2012-06-09

Hypothesis of this talk: Linked data is facts, but the idea of linked data is also

re-purposing,

⟹ re-presenting,

⟹ re-narrating,

to achieve an understandable dialogue



Semantic Web / Linked Data


ThetemperatureinMilwaukeeis100°F. - various syntaxes - Locutionary act:


- RDF/OWL interpretation –



Data is not Text

Quantity: One triple vs big data

➯ What is the right amount?

Pertinence: Pertinence to dialogue

➯ Does the discussion/interaction determine data selection?

Manner: Data is not sequential

➯ No implicit ordering contained in the data (e.g. birthdata before date of death)



Semantic Web / Linked Data


ThetemperatureinMilwaukeeis100°F. - various syntaxes - Locutionary act:


- RDF/OWL interpretation –

Generic applications easily

violate Grice‘s maxims!

Quantity Quality Pertinence Manner

Lead question:Does the Semantic Web have a pragmatics layer?How would this look like?



CONCEPTUAL NAVIGATION MODEL



Hypertextual Navigation (from D. Schwabe)

What does it mean to click here? Semantics is clear, but Pragmatics?

Context + Grice‘s Pertinence!

[Bomfim & Schwabe, 2011]




Input: LOD + Navigation Model + other stuff

Navigation Model A Context is a set of resources that share similar

navigation opportunities.• Context:Navigation ⇔Class:Structure+Behavior

Navigation Metamodel




Hitting a link of type „Organization“ means different things in different contexts!

Here is one!



PROGRAMMING WITH LINKED DATA = INTERACTING WITH LINKED DATA

[Schegelmann et al 2012]



Mapping Linked Data and OO Programming

Linked Data Meaning/Semantics

Concept Properties Instances

Object orientation Meaning/Semantics

Classes Attributes/Methods Objects

Pragmatics Classes

• Visible and used by whom?

• Orchestration of method calls

Responsibility-driven



Why is Linked Data Programming Tricky?

Developing Core Ontologies Software: Core Ontology of Software (COS) Services: Core Ontology of Software Components (COSC) Multimedia: Core Ontology of Multimedia (COMM) Events: Core Ontology of Events (F) Desktop: Core Semantic Inf. Mgmt. Ontology (COSIMO)

Main Criteria: Reusability Plugability

Main Drawback: Programmability



What Jeopardizes Programmability?

Challenges on (RDF) knowledge representation N-ary relations (denormalization) Aspect on relationships („Tim has high temp, but falling“) Roles as additional objects

(lifetime different from rigid object) Different roles being played in different contexts

(descriptions and situations)

Solution [Schegelmann et al 2012]: –Different ontology patterns to the rescue–Easy to use APIs

http://www.w3.org/TR/swbp-n-aryRelations/



Pattern for Image Tagging

[Scherp&Saathoff, WWW-2010][Troncy et al 2007]



Ontology API Model for Image Tagging



Automatically Generated Ontology API



Comparing the two structures



OntoMDE Workflow

Model of Ontologies (MoOn)Adding declarative layer:Structuring the ontologies intosemantic units

Ontology API Model (OAM)Adding declarative layer:Structuring pragmatic units specifying how entities are to be used together



RANKING



More data here …

More data here …

Which links to follow? Where to go next?What information is there?What are the „good“ links … … leading to „good“ resources?



Relevance Ranking for Linked Data

Apply Web Ranking,e.g. HITS, PageRank, …

TripleRank

Who is loved/hated most?



Linked Data as Tensor

Transformationto 3-D-Tensor

[Franz et al, 2009][Nickel et al, 2012]

Then: PARAFAC analysis



Evaluation

16 test persons Faceted browsing scenario What are the most

interesting, most related, most useful resources (objects)?

10 queries



TR7.594

TR3.251

TR2.413

BL3.948

BL1.207

BL1.626

0

1

2

3

4

5

6

7

8

Total Results Positives Negatives

TR

BL

Evaluation: Results

1387 answers, overall inter-rater agreement: 0.7 (0 ≤ agreement ≤ 1)

Doubled recallwithout loss of precision!



CONCLUSION



Syntax

Semantics

Pragmatics

MetamodelsPatternsRankings...



Issue: From Data to Understanding

CognitionStorytellingPragmatics

Ontology PatternsConceptual Modeling

Metamodels...

QuantityPertinenceManner



Hypertext Community

Linking people

Make linked data understandable!

Linking data Linking stories

Linking resources



THANK YOU!



Literature

J. L. Austin. How to do things with words. Oxford University Press, 1962/1975.

M. H. de S. Bomfim, Daniel Schwabe. Design and Implementation of Linked Data Applications Using SHDM and Synth. Int. Conf. Web Engineering 2011, pp. 121-136.

T. Franz, A. Schultz, S. Sizov, S. Staab: TripleRank: Ranking Semantic Web Data by Tensor Decomposition. International Semantic Web Conference 2009: 213-228

Chierchia, Gennaro.; McConnell-Ginet, Sally: Meaning and Grammar : An Introduction to Semantics. MIT Press, 1990.

Maximilian Nickel, Volker Tresp, Hans-Peter Kriegel: Factorizing YAGO: scalable machine learning for linked data. WWW 2012: 271-280

E. Pietriga, C. Bizer, D. Karger, R. Lee: Fresnel: A Browser-Independent Presentation Vocabulary for RDF. International Semantic Web Conference 2006, Springer 158-171.

S. Schenk, C. Saathoff, S. Staab, A. Scherp. SemaPlorer – Interactive Semantic Exploration of Data and Media based on a Federated Cloud Infrastructure. In Journal of Web Semantics, Elsevier, 7(4), 2009.

C. Saathoff, A. Scherp: Unlocking the semantics of multimedia presentations in the web with the multimedia metadata ontology. WWW 2010: 831-840

R. Troncy, O. Celma, S. Little, R. García and C. Tsinaraki. MPEG-7 based Multimedia Ontologies: Interoperability Support or Interoperability Issue? In Workshop on Multimedia Annotation and Retrieval enabled by Shared Ontologies (MAReSO'07), Genova, Italy, December 5, 2007. http://www.eurecom.fr/~troncy/Publications/Troncy-mareso07.pdf

How to Do Things with Triples

Technology

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