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. . .1 Practical Issues Topics . Exam and Assigments Multi Agent Semantics Web Systems: Overview . . Reading . . . .

Ewan Klein . . .2 MASWS: Diving Into the School of Informatics High-Level View Semantics? MASWS — 16 January 2012 Mashups Outlook

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Background Key Topics and Challenges

Weeks 1–5 [Ewan] Infrastructure for connecting web-scale data at the semantic level Platform-specific (Windows, Linux, MacOS, …) apps vs. web/browser-as-platform/cloud + interoperability Representing and reasoning with semantics at web-scale Data deluge Web 1.0, Web 2.0, … Weeks 7–11 [Michael] Web as an unpredictable, risky and dynamic software environment Exposing applications and agents on the web as services Using agent models to support communication and coordination for web services

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For the Semantic Web (SW), we’ll mainly focus on Resource Description Written exam, 70% Framework (RDF) and associated technologies / tools. Coursework assignments, together worth 30%

Although OWL () is an important part of SW, we ▶ Two major assignments, plus one additional small assignment for MSc don’t have time to look at it properly. students emphasis on Semantic Web than Multi Agent Sytems — integration of the Exam will only test material from lectures (including guest lectures), from two still an open research question. coursework and from required reading.

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Coursework Assignments Reading

The lecture slides are not a text book! No single book covers the scope of the course, but two main texts: Not just a way of tormenting you — crucial for really understanding the material. You will be expected to do some programming as part of the assignments, but language is up to you. New: the two major assignments will be carried out in teams. By default, credit will be split equally amongst team members.

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Bob DuCharme. Querying and Updating with SPARQL 1.1. O’Reilly Media, 2011. In-depth guide to the standard semantic web query languagexs

Grigoris Antoniou and Frank van Harmelen. A Semantic Web Primer, 2nd Edition. MIT Press, 2008. Quite detailed presentations of XML, RDF and OWL.

Thomas B. Passin. Explorer’s Guide to the Semantic Web. Manning, 2004. Less technical than Antoniou & van Harmelen, but covers more topics.

Christopher Walton. Agency and the Semantic Web. Oxford University Press, 2007. Good coverage of MAS and their relevance to the Semantic Web

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Reading outside the box Let’s dive in!

There is lots of relevant literature available online — try to explore some of it! Also a lot of informal discussion in Twitter, portals, newsgroups, blogs, etc. Help create a dynamic resource on the MASWS Wiki: http://sites.google.com/site/masws09/

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I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web –– the content, links, and transactions between people and computers.

…the day-to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines.

Tim Berners-Lee (1999) Weaving the Web

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TBL: The Data Web Semantic Web

I don’t think [the Semantic Web is] a very good name but we’re stuck with it now. The word semantics is used by different groups to mean different things.

…I think we could have called it the Data Web. …it connects all applications together or gives [people] access to data across the company …

Tim Berners-Lee (2007), Interview in Business Week

Ewan Klein (School of Informatics) Multi Agent Semantics Web Systems: Overview MASWS — 16 January 2012 15 / 40 Ewan Klein (School of Informatics) Multi Agent Semantics Web Systems: Overview MASWS — 16 January 2012 16 / 40 The ‘semantics’ in Semantic Web Dublin Core: Commonly understood semantics

Discovery of information across …the is hindered by differences in terminology and descriptive practices from one field of knowledge to the next. The Dublin Core can help the ”digital tourist” Syntax / semantics distinction: long history in philosophy of language, …by supporting a common set of elements, the semantics of which linguistics, formal logic are universally understood and supported. For example, scientists Simple view: concerned with locating articles by a particular author, and art ▶ syntax concerned with arrangement of symbols scholars interested in works by a particular artist, can agree on the semantics concerned with relation between symbol strings and the world ▶ importance of a “creator” element. Such convergence on a common, if slightly more generic, element set increases the visibility and accessibility of all resources, both within a given discipline and beyond.

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Dublin Core: Creator Scenario

URI: http://purl.org/dc/elements/1.1/creator What are you doing on Burns night? Label: Creator Google “burns” Definition: An entity primarily responsible for making the resource. ⇒ Wikipedia article on Robert Burns Comment: Examples of a Creator include a person, an organization, or ⇒ a service. Typically, the name of a Creator should be used Amazon listing of books by Burns ⇒ to indicate the entity. Google Maps to look at birthplace of Burns ⇒

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Amazon Google Maps

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Wikipedia Amazon Google Earth

Wikipedia Amazon Google Maps

Web Page

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Web APIs Limitations of Web APIs

A large and growing number of web data sources provide program-accessible interfaces (APIs). The web site http://www.programmableweb.com currently lists 4,796 (2009: 1,556) APIs and 6,401 (2009: 4,506) Mashups. Most popular Web APIs: The interfaces are non-uniform — REST, RPC (e.g. SOAP) and hybrid The results are returned in a variet of formats — XML, JSON, Atom The data schemas tend to be provider-specific Militates against the development of portable, generic methods of accessing and using data

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Provide globally unique addresses for web documents: URLs Provide globally unique identifiers for things Enable all web documents to be accessible over HTTP Enable all data to be accessible over HTTP Use a standard format for web documents: HTML Use a standard format for data Link between documents: HREFs Use standardized schemas / vocabularies

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Semantic Web Linked Open Data

Provide globally unique identifiers for things: URIs As before, plus: Enable all data to be accessible over HTTP: HTTP URIs When a person or application looks up a URI, they get back some Use a standard format for data: Resource Description Framework (RDF) informative RDF Use standardized schemas / vocabularies: FOAF, Dublin Core, SIOC, … Include statements that link one dataset to another

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books:1855349825 books:1855349825

dc:creator dc:creator books:1855349825

:Robert_Burns dbpedia:Robert_Burns bm:hasOffer

http:www.amazon.com

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RDF Graphs RDF Mashup

books:1855349825

dc:creator bm:hasOffer

Wikipedia Amazon Google Earth http:www.amazon.com dbpedia:Robert_Burns

LQRAPS

Web Page

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Targets of semantic web are familiar:

▶ data integration,

▶ data inference, ▶ data classification,

▶ data visualization

Traditional tools can be used, but process is often too hard / time-consuming RDF lets you build things fast because models can evolve incrementally

http://www.thefigtrees.net/lee/blog/2011/09/saving_months_not_milliseconds.html

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The Semantic Markup Bottleneck Reading for this Week

How do we get enough data + schemas to obtain a ‘network effect’?

▶ Open data, open government: data.gov.uk, data.gov.us,… .1. Tim Berners-Lee, Jim Hendler and (2001) ‘The Semantic Web.’ ▶ Text processing of unstructured data . Scientific American, Vol. 284, pp. 34–43. Tim Berners-Lee LOD Example: . ..2 , Wendy Hall, Tim Berners-Lee (2006). ‘The Semantic Web data on health care expenditures for a given geographical area Revisited.’ IEEE Intelligent Systems.

data about the health and lifestyle characteristics of the population of that PDF versions available from course web page. region assess effectiveness of the government programme ⇒

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