The document summarizes the past 10 years of social networks and the Semantic Web. It discusses how early visions of a decentralized, interoperable Social-Semantic Web did not fully materialize due to social networks consolidating user data into silos. However, work continues through standards bodies to develop vocabularies and building blocks that could still enable a federated social web. It also notes that while online social science is now widespread, challenges remain around access to social data and the ability to generalize findings over time and platforms.

1. Social networks and the Semantic Web:
A retrospective of the past 10 years
P R E S E N T E D B Y P e t e r M i k a , D i r e c t o r , S e m a n t i c S e a r c h , Y a h o o L a b s ⎪ M a y 1 8 ,
2 0 1 5

2. Based on interviews with:
2
 John Breslin
› Senior Lecturer in Informatics and Engineering at NUI Galway
› Researcher, Unit Leader at the Insight Centre for Data Analytics (formerly DERI)
› Creator of SIOC
› Co-founder and Director of boards.ie
 Harry Halpin
› Team member at W3C
› Post-doc at CSAIL, MIT
› Author of Social Semantics: The Search for Meaning on the Web
› W3C team contact for the Social Web WG
 Henry Story
› Co-founder and CTO of Stample
› Previously Social Web architect at Sun Microsystems
› W3C WebID XG chair (now WebID CG)

3. The idea of the Social-Semantic Web
3

4.  “At the doctor's office, Lucy instructed her
Semantic Web agent through her handheld Web
browser. The agent promptly retrieved
information about Mom's prescribed treatment
from the doctor's agent, looked up several lists
of providers, and checked for the ones in-plan
for Mom's insurance within a 20-mile radius of
her home and with a rating of excellent or very
good on trusted rating services. It then began
trying to find a match between available
appointment times (supplied by the agents of
individual providers through their Web sites) and
Pete's and Lucy's busy schedules.”
 (The emphasized keywords indicate terms
whose semantics, or meaning, were defined for
the agent through the Semantic Web.)
5/18/20154
The Semantic Web (2001)

5. One slide intro to the Semantic Web
 Create URIs for real-world things, not just web resources
› (In practice) URIs are composed of namespace + localname
› Joe the Person has the URI ns:Joe
 Basic unit of information is a triple
› A tuple of (subject, predicate, object)
› Example: (ns:Joe, type, Person),
(#Joe, name, “John Doe”)
 An RDF model is a set of triples
› Standalone RDF documents: RDF/XML, JSON-LD
› Embedded inside HTML: RDFa, JSON-LD
 Schemas (ontologies) are also represented
in the same model
ns:Joe
“John Doe”
foaf:name
foaf:Personrdf:type
rdfs:subclassOf
foaf:Agent

6. Data distributed across the Web
Joe’s homepage
Joe’s blog
Mary’s homepage
(#name, #type, #Property)
(#name, #domain, #Person)
schema doc
(#joe, #name, “Joe A.”)
(#joe, #email, mailto:joe@joe.com)
(#joe, #loves, #mary)
(#mary, name, “Mary B.”)
(#mary, gender, “female”)

7. The Semantic Web off to a slow start
 Standardization ahead of adoption
› URI, RDF, RDF/XML, RDFa, JSON-LD,
OWL, RIF, SPARQL, OWL-S, POWDER …
 Chicken and egg problem
› No data consumers/apps,
hence no incentive to publish data
› No data means no interested consumers/apps

8. The Social Web
 The Social Web followed web architecture
› Links, blogrolls, pingbacks etc. between individual homepages and blogs
› First SNSs (e.g. LiveJournal) simply implemented the same within one system
› Typical usage is browsing from blog to blog or profile to profile
Alice’s blog
Bob’s blog
Charlie’s blogreads reads
links to

9. The promise of the Social-Semantic Web
9
 The Semantic Web as the ideal platform for distributed social networks
› Connect digital identities across networks (sameAs)
› Connect distributed conversations across networks
› Having a profile in one network, and linking it to content elsewhere
› Fine-grained access control through existing web protocols
› Competition in services, e.g. search over social content
 A boon to Online Social Science
› Tools for data acquisition, data fusion, storage and querying
› Significantly increase the size, frequency and longitude of social studies through digital
data collection
› Contribute to the improvement of technology by the study of technology usage

10. Putting it together:
Social networks and the Semantic Web
10
Semantic Web
Online social networks
Social-Semantic Web Online Social Science
enables
informs the design of
The Social-Semantic Web aims at creating shared representations of social data and
improving the interoperability of social applications online, in the benefit of (a) the Semantic
Web and (b) the study of online social behaviour.

11. What happened?
11

12. What happened to the Semantic Web?
 Consolidation in terms of the technology stack
› RDF/XML turned out to be a dead-end
› JSON-LD winning developer hearts (e.g. at Yahoo)
› RDFa and Microdata preferred over microformats (e.g. OGP, schema.org)
 SPARQL provides a query language and protocol
› But still few RDF triple-stores directly accessible on the Web
 Tooling improved
› Editors, validators, annotators, query composers, browsers, RDF APIs etc.
 Linked Data Platform (2015) a step toward a Read/Write Semantic Web
› Crucial for social applications wanting to read/write profile information and content

13. What happened to the Semantic Web? (2)
13
 Data publishing (finally) starts to take off
1. Linked Open Data
• Opening up existing data sets
• Encyclopedic, scientific and government data
• see linkeddata.org and the LDOW workshop
1. Metadata in HTML
• Annotating existing HTML pages
• Driven by search engine applications
• see schema.org and applications at
Bing/Yahoo/Google/Yandex
 But not much social data…

14. 14
What happened to the Social Web?

15. What happened to the Social Web? Post-2004
 “Web 2.0”: commercial interests in social data lead to silos
› Data portability possible (e.g. Google’s Takeout), but no interlinking.
 New social networks still arise
› Special purpose (dating, health) or just fresh new ground (Snapchat)
› Enterprise, e.g. Yammer
Alice’s profile
Bob’s profile
Charlie’s profilefollows follows
internally link to
Facebook
Alice’s profile
Bob’s profile
Charlie’s profilefollows follows
internally link to
Twitter
Alice’s profile
Bob’s profile
Charlie’s profilefollowsfollows
internally link to
Alice’s profile
Bob’s profile
Charlie’s profile
follows follows
internally link to
Alice’s profile
Bob’s profile
Charlie’s profilefollows follows
internally link to

16. What happened to the Social-Semantic Web?
16
 Representations
› Profile data and content
• FOAF (Friend-of-a-Friend) ontology (2000) for profile information
• SIOC (Semantically Interlinked Online communities) ontology (2004) for blogs, forums, Q&A sites
› Activities/actions
• ActivityStreams 2.0
• schema.org Actions vocabulary
 Missing building blocks for decentralized OSNs come from elsewhere
› Distributed authentication (OpenID) & authorization (Oauth)
› Alternatives based on Semantic Web principles come late (but not too late?)
• WebID and WebID + TLS
• SoLiD: Social Linked Data platform

17. What is left of our hopes for the Social-Semantic Web?
17
 Connect digital identities across networks (sameAs)
› One-off interlinking between systems, e.g. link your Facebook to your Yahoo account
 Connect distributed conversations across networks
› Limited solutions, e.g. hashtag directories such as
 Having a profile in one network, and linking it to content elsewhere
› Not possible
 Fine-grained access control through existing web protocols
› Not possible
 Competition in services, e.g. search over social content
› Non-existent despite early experiments (foaf-search.net)

18. The work continues
18
 W3C Social Activity
› W3C Social Interest Group
• Use cases TF
• Vocabularies TF
› W3C Social Web Working Group
• An extensible transfer syntax for activities like status updates
• An API for third-party social content embedding
• Possibly a protocol for federation
 W3C WebID Community Group

19. What happened to online social science?
19
 Online social science is booming
1. Studies of online social phenomena
• Qualitative
– Digital ethnography, e.g. danah boyd’s work
• Quantitative
– Networks
– Language/content
2. Validating existing social theory using online data
3. Predicting real world phenomena using online data
 Still, mostly done by computer scientists
› We failed to provide much support for social scientists in terms of either data or tooling

20. Challenges
20
 Limited access to data and experimentation platforms
› As a result, studies are still small-scale and one-off
 Validation studies challenged by social scientists
› Online not the same as real-world sociality
 Studies don’t necessarily generalize across social sites or contexts
› e.g. ‘we predict the next election using Twitter’-type studies have been questioned
 Affordances and usage keeps changing over time
› SNSs have become more media-centric, less profile-centric
› See Ellison, Nicole and danah boyd. (2013). “Sociality through Social Network Sites.”

21. Final thoughts
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 Semantic Web technology
› Too little, too late for the Social Web? Or can we still build a federated social web?
• e.g. can initiatives such as FreedomBox take us back to the early Social Web?
 Online Social Science
› What more can we do with technology?

22. Q&A
 Contact me
› pmika@yahoo-inc.com
› @pmika
› http://www.slideshare.net/pmika/