n NESSTAR: A Semantic Web Application for Statistical Data and Metadata Pasqualino “Titto” Assini Nesstar Ltd - UK

Nesstar - Networked Social Science Tools and Resources n nesstar NESSTAR: NEtworked Social Science Tools And Resources (a.k.a. the “Data Web”) –What is all about? The domain: statistical information. –What is the “Data Web”? –End User and Data Publisher Views –Requirements The Underlying Architecture: NEsstar Object Oriented Middleware (NEOOM) –Web Oriented: based on Semantic Web technology –Object Oriented –Domain Independent Implementation Design and Development Process Contents

Nesstar - Networked Social Science Tools and Resources n nesstar The Domain: Surveys, Opinion Polls, Censuses The Actors: –Data Publishers: Social Sciences Data Archives, Statistical Offices, Private Research Institutes (Gallup, etc) –Data Users: Social Researchers, Journalists, Marketing Experts The Problem –Simplify publishing, finding and accessing statistical information. The Domain and the Problem

Nesstar - Networked Social Science Tools and Resources n nesstar The Web is a very successful example of a distributed information dissemination system Can we learn something from the Web? Idea: Use (Semantic) Web principles and technologies to create a “Data Web” Learning From the Web

Nesstar - Networked Social Science Tools and Resources n nesstar What is the Data Web? The Data Web is the application of Semantic Web techniques and principles to the problem of distributed data dissemination and processing.

Nesstar - Networked Social Science Tools and Resources n nesstar User view: Data Web Browser LOCATION BAR OBJECT BROWSER BOOKMARKS OPERATION OPERATION RESULT BROWSING

Nesstar - Networked Social Science Tools and Resources n nesstar Publisher View: Object Model PROPERTIES RELATIONSHIPS TYPE METHODS INHERITANCE

Nesstar - Networked Social Science Tools and Resources n nesstar Requirements Support for the Object Model: –An interface definition language that supports Types, Properties, Relationships and Methods  RDF Schema (no Methods) Distributed object model extensibility: –Inheritance  RDF Integration with the Web: –Objects, Types and method invocations have a URL –Object state is accessible via HTTP  Objects (and types) self-describe themselves in RDF –Method invocations can be performed via HTTP  SOAP, HTML FORM

Nesstar - Networked Social Science Tools and Resources n nesstar Semantic Web (RDF/RDF Schema) plus: –Self-description principle: objects and types self- describe themselves by making accessible their RDF description at their URL (dynamic discovery) –RDF Schema Model for Methods –Method Invocation Protocol based on HTML FORM Nesstar Object Oriented Middleware

Nesstar - Networked Social Science Tools and Resources n nesstar Method Model

Nesstar - Networked Social Science Tools and Resources n nesstar Method Invocations are: –Performed as HTML FORM methods  Very easy to generate forms that correspond to method invocations –Coded as normal URLs: Ex: &userID=admin&userPassword=mypwd Method Invocation Protocol

Nesstar - Networked Social Science Tools and Resources n nesstar A machine-understandable Data Web closely integrated with the (Semantic) Web. Advantages: –Support for sophisticated Object Oriented Models –Distributed Extensibility –Integration with the (Semantic) Web –Compatibility With Existing Languages/Protocols/Applications –Programming Language Independence What Have We Got?

Nesstar - Networked Social Science Tools and Resources n nesstar System Components

Nesstar - Networked Social Science Tools and Resources n nesstar Design/Development Use Cases

Nesstar - Networked Social Science Tools and Resources n nesstar Presentation Layer Independence

Nesstar - Networked Social Science Tools and Resources n nesstar Web Links to Statistical Objects This is a Nesstar Server object … Get linked objects

Nesstar - Networked Social Science Tools and Resources n nesstar Web Links to Statistical Operations

Demo Object Browser (new EJB Server)Object Browser Data Archive Server