Posted:August 30, 2010

The Recent Pace of Ontology Development Appears to Have Waned

The development of ontologies goes by the names of ontology engineering or ontology building, and can also be investigated under the rubric of ontology learning. This paper summarizes key papers and links to this topic [18].

For the last twenty years there have been many methods put forward for how to develop ontologies. These methodological activities have actually diminished somewhat in recent years.

The main thrust of the papers listed herein is on domain ontologies, which model particular domains or topic areas. (As opposed to reference, upper or theoretical ontologies, which are more general or encompassing.) Also, little commentary is offered on any of the individual methodologies; please see the referenced papers for more details.

General Surveys

One of the first comprehensive surveys was done by Jones et al. in 1998 [1]. This study began to elucidate common stages and noted there are typically separate stages to produce first an informal description of the ontology and then its formal embodiment in an ontology language. The existence of these two descriptions is an important characteristic of many ontologies, with the informal description often carrying through to the formal description.

The next major survey was done by Corcho et al. in 2003 [2]. This built on the earlier Jones survey and added more recent methods. The survey also characterized the methods by tools and tool readiness.

More recently the work of Simperl and her colleagues has focused on empirical results of ontology costing and related topics. This series has been the richest source of methodology insight in recent years [3, 4, 5, 6]. More on this work is described below.

Though not a survey of methods, one of the more attainable descriptions of ontology building is Noy and McGuinness’ well-known Ontology Development 101 [7]. Also really helpful are Alan Rector’s various lecture slides on ontology building [8].

However, one general observation is that the pace of new methodology development seems to have waned in the past five years or so. This does not appear to be the result of an accepted methodology having emerged.

Some Specific Methodologies

Some of the leading methodologies, presented in rough order from the oldest to newest, are as follows:

  • Cyc – this oldest of knowledge bases and ontologies has been mapped to many separate ontologies. See the separate document on the Cyc mapping methodology for an overview of this approach [9]
  • TOVE (Toronto Virtual Enterprise) – a first-order logic approach to representing activities, states, time, resources, and cost in an enterprise integration architecture [10]
  • IDEF5 (Integrated Definition for Ontology Description Capture Method) – is part of a broader set of methodologies developed by Knowledge Based Systems, Inc. [11]
  • ONIONS (ONtologic Integration Of Naive Sources) – a set of methods especially geared to integrating multiple information sources [12], with a particular emphasis on domain ontologies
  • COINS (COntext INterchange System) – a long-running series of efforts from MIT’s Sloan School of Management [13]
  • METHONTOLOGY – one of the better known ontology building methodologies; however, not many known uses [14]
  • OTK (On-To-Knowledge) was a methodology that came from the major EU effort at the beginning of last decade; it is a common sense approach reflected in many ways in other methodologies [15]
  • UPON (United Process for ONtologies) – is a UML-based approach that is based on use cases, and is incremental and iterative [16].

Please note that many individual projects also describe their specific methodologies; these are purposefully not included. In addition, Ensan and Du look at some specific ontology frameworks (e.g., PROMPT, OntoLearn, etc.) from a domain-specific perspective [17].

Some Flowcharts

Here is the general methodology as presented in the various Simperl et al. papers [c.f., Fig. 1 in 3]:

Ontology Engineering from Simperl et al.

The Corcho et al. survey also presented a general view of the tools plus framework necessary for a complete ontology engineering environment [Fig. 4 from 2]:

Ontology Tools and Framework from Corcho et al.There are more examples that show ontology development workflows. Here is one again from the Simperl et al. efforts [Fig. 2 in 5]:

Ontology Learning Flowchart from Simperl et al.However, what is most striking about the review of the literature is the paucity of methodology figures and the generality of those that do exist. From this basis, it is unclear what the degree of use is for real, actionable methods.

Best Practices Observations

The Simperl and Tempich paper [3], besides being a rich source of references, also provides some recommended best practices based on their comparative survey. These are:

General Recommendations

  • Enforce dissemination, e.g.. publish more best practices
  • Define selection criteria for methodologies
  • Define a unified methodology following a method engineering approach
  • Support decision for the appropriate formality level given a specific use case

Process Recommendations

  • Define selection criteria for different knowledge acquisition (KA) techniques
  • Introduce process description for the application of different KA techniques
  • Improve documentation of existing ontologies
  • Improve ontology location facilities
  • Build robust translators between formalisms
  • Build modular ontologies
  • Define metrics for ontology evaluation
  • Offer user oriented process descriptions for ontology evaluation

Organizational Recommendations

  • Provide ontology engineering activity descriptions using domain-specific terminology
  • Improve consensus making process support

Technological Recommendations

  • Provide tools to extract ontologies from structured data sources
  • Build lightweight ontology engineering environments
  • Improve the quality of tools for domain analysis, ontology evaluation, documentation
  • Include methodological support in ontology editors
  • Build tools supporting collaborative ontology engineering.

Summary of Observations

This review has not set out to characterize specific methodologies, nor their strengths and weaknesses. Yet the research seems to indicate this state of methodology development in the field:

  • Very few discrete methods exist, and those that do are relatively older in nature
  • The methods tend to either cluster into incremental, iterative ones or those more oriented to more comprehensive approaches
  • There is a general logical sharing of steps across most methodologies from assessment to deployment and testing and refinement
  • Actual specifics and flowcharts are quite limited; with the exception of the UML-based systems, most appear not to meet enterprise standards
  • The supporting toolsets are not discussed much, and most of the examples are based solely on a governing tool. Tool integration and interoperability is almost non-existent in terms of the narratives
  • This does not appear to be a very active area of current research.

[1] D.M. Jones, T.J.M. Bench-Caponand, P.R.S. Visser, 1998.“Methodologies for Ontology Development,” in Proceedings of the IT and KNOWS Conference of the 15th FIP World Computer Congress, 1998. See
[2] O. Corcho, M. Fernandez and A. Gomez-Perez, 2003. “Methodologies, Tools and Languages for Building Ontologies: Where is the Meeting Point?,” in Data & Knowledge Engineering 46, 2003. See
[3] Elena Paslaru Bontas Simperl and Christoph Tempich, 2006. Ontology Engineering: A Reality Check, in Proceedings of the 5th International Conference on Ontologies, Databases, and Applications of Semantics ODBASE2006, 2006. See;jsessionid=DE3414C0282C76F0EA787A06039941D2.
[4] Elena Paslaru Bontas Simperl, Christoph Tempich, and York Sure, 2006. “ONTOCOM: A Cost Estimation Model for Ontology Engineering,” presented at ISWC 2006; see
[5] Elena Simperl, Christoph Tempich and Denny Vrandečić, 2008. “A Methodology for Ontology Learning,” in Frontiers in Artificial Intelligence and Applications 167 from the Proceedings of the 2008 Conference on Ontology Learning and Population: Bridging the Gap between Text and Knowledge, pp. 225-249, 2008. See 20THE%20GAP%20BETWEEN%20TEXT%20AND%20KNOWLEDGE.pdf#page=241.
[6] Elena Simperl, Malgorzata Mochol and Tobias Burger, 2010. “Achieving Maturity: the State of Practice in Ontology Engineering in 2009,” in International Journal of Computer Science and Applications, 7(1), pp. 45 – 65, 2010. See
[7] Natalya F. Noy and Deborah L. McGuinness, 2001. “Ontology Development 101: A Guide to Creating Your First Ontology,” Stanford University Knowledge Systems Laboratory Technical Report KSL-01-05, March 2001. See
[9] Stephen L. Reed and Douglas B. Lenat, 2002. Mapping Ontologies into Cyc, paper presented at AAAI 2002 Conference Workshop on Ontologies For The Semantic Web, Edmonton, Canada, July 2002. See . Also, as presented by Doug Foxvog, Ontology Mapping with Cyc, at WMSO, June 14, 2004; see Also, see Matthew E. Taylor, Cynthia Matuszek, Bryan Klimt, and Michael Witbrock, 2007. “Autonomous Classification of Knowledge into an Ontology,” in The 20th International FLAIRS Conference (FLAIRS), Key West, Florida, May 2007. See
[10] M. Gruninger and M.S. Fox, 1994. “The Design and Evaluation of Ontologies for Enterprise Engineering”, Workshop on Implemented Ontologies, European Conference on Artificial Intelligence 1994, Amsterdam, NL. See
[11] KBSI, 1994. “The IDEF5 Ontology Description Capture Method Overview”, Knowledge Based Systems, Inc. (KBSI) Report, Texas. The report describes the stages of: 1) organizing and scoping; 2) data collection; 3) data analysis; 4) initial ontology development; and 5) ontology refinement and validation. See
[12] A. Gangemi, G. Steve and F. Giacomelli, 1996. “ONIONS: An Ontological Methodology for Taxonomic Knowledge Integration”, ECAI-96 Workshop on Ontological Engineering, Budapest, August 13th. See
[13] The COINS approach was developed by Madnick et al. over the past two decades or so at the MIT Sloan School of Management. See further for a listing of papers from this program; some are use cases, and some are architecture-related. For the most detailed treatment, see Aykut Firat, 2003. Information Integration Using Contextual Knowledge and Ontology Merging, Ph.D. Thesis for the Sloan School of Management, MIT, 151 pp. See
[14] M. Fernandez, A. Gomez-Perez and N. Juristo, 1997. “METHONTOLOGY: From Ontological Art Towards Ontological Engineering”, AAAI-97 Spring Symposium on Ontological Engineering, Stanford University, March 24-26th, 1997.
[15] York Sure, Christoph Tempich and Denny Vrandecic , 2006. “Ontology Engineering Methodologies,” in Semantic Web Technologies: Trends and Research in Ontology-based Systems, pp. 171-187, Wiley. The general phases of the approach are: 1) feasibility study; 2) kickoff; 3) refinement; 4) evaluation; and 5) application and evolution.
[16] A. De Nicola, M. Missikoff, R. Navigli, 2009. “A Software Engineering Approach to Ontology Building”. Information Systems, 34(2), Elsevier, 2009, pp. 258-275.
[17] Faezeh Ensan and Weichang Du, 2007. Towards Domain-Centric Ontology Development and Maintenance Frameworks; see
[18] This document is permanently archived on the OpenStructs TechWiki. This document is part of a current series on ontology development and tools to be completed over the coming weeks.

Posted by AI3's author, Mike Bergman Posted on August 30, 2010 at 12:53 am in Ontologies, Ontology Best Practices | Comments (2)
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Posted:August 23, 2010

AI3's Ontologies categoryEarlier Listing is Expanded by More than 30%

At the beginning of this year Structured Dynamics assembled a listing of ontology building tools at the request of a client. That listing was presented as The Sweet Compendium of Ontology Building Tools. Now, again because of some client and internal work, we have researched the space again and updated the listing [1].

All new tools are marked with <New> (new only means newly discovered; some had yet to be discovered in the prior listing). There are now a total of 185 tools in the listing, 31 of which are recently new, and 45 added at various times since the first release. <Newest> reflects updates — most from the developers themselves — since the original publication of this post.

Comprehensive Ontology Tools

  • Altova SemanticWorks is a visual RDF and OWL editor that auto-generates RDF/XML or nTriples based on visual ontology design. No open source version available
  • Amine is a rather comprehensive, open source platform for the development of intelligent and multi-agent systems written in Java. As one of its components, it has an ontology GUI with text- and tree-based editing modes, with some graph visualization
  • The Apelon DTS (Distributed Terminology System) is an integrated set of open source components that provides comprehensive terminology services in distributed application environments. DTS supports national and international data standards, which are a necessary foundation for comparable and interoperable health information, as well as local vocabularies. Typical applications for DTS include clinical data entry, administrative review, problem-list and code-set management, guideline creation, decision support and information retrieval.. Though not strictly an ontology management system, Apelon DTS has plug-ins that provide visualization of concept graphs and related functionality that make it close to a complete solution
  • DOME is a programmable XML editor which is being used in a knowledge extraction role to transform Web pages into RDF, and available as Eclipse plug-ins. DOME stands for DERI Ontology Management Environment
  • FlexViz is a Flex-based, Protégé-like client-side ontology creation, management and viewing tool; very impressive. The code is distributed from Sourceforge; there is a nice online demo available; there is a nice explanatory paper on the system, and the developer, Chris Callendar, has a useful blog with Flex development tips
  • <Newest> ITM supports the management of complex knowledge structures (metadata repositories, terminologies, thesauri, taxonomies, ontologies, and knowledge bases) throughout their lifecycle, from authoring to delivery. ITM can also manage alignments between multiple knowledge structures, such as thesauri or ontologies, via the integration of INRIA’s Alignment API. Commercial; from Mondeca
  • Knoodl facilitates community-oriented development of OWL based ontologies and RDF knowledge bases. It also serves as a semantic technology platform, offering a Java service-based interface or a SPARQL-based interface so that communities can build their own semantic applications using their ontologies and knowledgebases. It is hosted in the Amazon EC2 cloud and is available for free; private versions may also be obtained. See especially the screencast for a quick introduction
  • The NeOn toolkit is a state-of-the-art, open source multi-platform ontology engineering environment, which provides comprehensive support for the ontology engineering life-cycle. The v2.3.0 toolkit is based on the Eclipse platform, a leading development environment, and provides an extensive set of plug-ins covering a variety of ontology engineering activities. You can add these plug-ins or get a current listing from the built-in updating mechanism
  • ontopia is a relative complete suite of tools for building, maintaining, and deploying Topic Maps-based applications; open source, and written in Java. Could not find online demos, but there are screenshots and there is visualization of topic relationships
  • Protégé is a free, open source visual ontology editor and knowledge-base framework. The Protégé platform supports two main ways of modeling ontologies via the Protégé-Frames and Protégé-OWL editors. Protégé ontologies can be exported into a variety of formats including RDF(S), OWL, and XML Schema. There are a large number of third-party plugins that extends the platform’s functionality
    • Protégé Plugin Library – frequently consult this page to review new additions to the Protégé editor; presently there are dozens of specific plugins, most related to the semantic Web and most open source
    • Collaborative Protégé is a plug-in extension of the existing Protégé system that supports collaborative ontology editing as well as annotation of both ontology components and ontology changes. In addition to the common ontology editing operations, it enables annotation of both ontology components and ontology changes. It supports the searching and filtering of user annotations, also known as notes, based on different criteria. There is also an online demo
    • <New>Web Protégé is an online version of Protégé attempting to capture all of the native functionality; still under development
  • <New>Sigma is open source knowledge engineering environment that includes ontology mapping, theorem proving, language generation in multiple languages, browsing, OWL read/write, and analysis. It includes the Suggested Upper Merged Ontology (SUMO), a comprehensive formal ontology. It’s under active development and use
  • TopBraid Composer is an enterprise-class modeling environment for developing Semantic Web ontologies and building semantic applications. Fully compliant with W3C standards, Composer offers comprehensive support for developing, managing and testing configurations of knowledge models and their instance knowledge bases. It is based on the Eclipse IDE. There is a free version (after registration) for small ontologies
  • <New>TwoUse Toolkit is an implementation of current OMG and W3C standards for developing ontology-based software models and model-based OWL2 ontologies, largely based around UML. There are a variety of tools, including graphics editors, with more to come
  • <New>Wandora is a topic maps engine written in Java with support for both in-memory topic maps and persisting topic maps in MySQL and SQL Server. It also contains an editor and a publishing system, and has support for automatic classification. It can read OBO, RDF(S), and many other formats, and can export topic maps to various graph formats. There is also a web-based topic maps browser, and graphical visualization.

Not Apparently in Active Use

  • Adaptiva is a user-centred ontology building environment, based on using multiple strategies to construct an ontology, minimising user input by using adaptive information extraction
  • Exteca is an ontology-based technology written in Java for high-quality knowledge management and document categorisation, including entity extraction. Though code is still available, no updates have been provided since 2006. It can be used in conjunction with search engines
  • IODT is IBM’s toolkit for ontology-driven development. The toolkit includes EMF Ontolgy Definition Metamodel (EODM), EODM workbench, and an OWL Ontology Repository (named Minerva)
  • KAON is an open-source ontology management infrastructure targeted for business applications. It includes a comprehensive tool suite allowing easy ontology creation and management and provides a framework for building ontology-based applications. An important focus of KAON is scalable and efficient reasoning with ontologies
  • Ontolingua provides a distributed collaborative environment to browse, create, edit, modify, and use ontologies. The server supports over 150 active users, some of whom have provided us with descriptions of their projects. Provided as an online service; software availability not known.

Vocabulary Prompting Tools

  • AlchemyAPI from Orchestr8 provides an API based application that uses statistical and natural language processing methods. Applicable to webpages, text files and any input text in several languages
  • BooWa is a set expander for any language (formerly known as SEALS); developed by RC Wang of Carnegie Mellon
  • Google Keywords allows you to enter a few descriptive words or phrases or a site URL to generate keyword ideas
  • Google Sets for automatically creating sets of items from a few examples
  • Open Calais is free limited API web service to automatically attach semantic metadata to content, based on either entities (people, places, organizations, etc.), facts (person ‘x’ works for company ‘y’), or events (person ‘z’ was appointed chairman of company ‘y’ on date ‘x’). The metadata results are stored centrally and returned to you as industry-standard RDF constructs accompanied by a Globally Unique Identifier (GUID)
  • Query-by-document from BlogScope has a nice phrase extraction service, with a choice of ranking methods. Can also be used in a Firefox plug-in (not texted with 3.5+)
  • SemanticHacker (from Textwise) is an API that does a number of different things, including categorization, search, etc. By using ‘concept tags’, the API can be leveraged to generate metadata or tags for content
  • TagFinder is a Web service that automatically extracts tags from a piece of text. The tags are chosen based on both statistical and linguistic analysis of the original text
  • has a demo and an API for automatic tagging of web documents and texts. Tags can be single words only. The tool also recognizes named entities such as people names and locations
  • TermExtractor extracts terminology consensually referred in a specific application domain. The software takes as input a corpus of domain documents, parses the documents, and extracts a list of “syntactically plausible” terms (e.g. compounds, adjective-nouns, etc.)
  • TermFinder uses Poisson statistics, the Maximum Likelihood Estimation and Inverse Document Frequency between the frequency of words in a given document and a generic corpus of 100 million words per language; available for English, French and Italian
  • TerMine is an online and batch term extractor that emphasizes part of speech (POS) and n-gram (phrase extraction). TerMine is the terminological management system with the C-Value term extraction and AcroMine acronym recognition integrated
  • Topia term extractor is a part-of-speech and frequency based term extraction tool implemented in python. Here is a term extraction demo based on this tool
  • Topicalizer is a service which automatically analyses a document specified by a URL or a plain text regarding its word, phrase and text structure. It provides a variety of useful information on a given text including the following: Word, sentence and paragraph count, collocations, syllable structure, lexical density, keywords, readability and a short abstract on what the given text is about
  • TrMExtractor does glossary extraction on pure text files for either English or Hungarian
  • Wikify! is a system to automatically “wikify” a text by adding Wikipedia-like tags throughout the document. The system extracts keywords and then disambiguates and matches them to their corresponding Wikipedia definition
  • Yahoo! Placemaker is a freely available geoparsing Web service. It helps developers make their applications location-aware by identifying places in unstructured and atomic content – feeds, web pages, news, status updates – and returning geographic metadata for geographic indexing and markup
  • Yahoo! Term Extraction Service is an API to Yahoo’s term extraction service, as well as many other APIs and services in a variety of languages and for a variety of tasks; good general resource. The service has been reported to be shut down numerous times, but apparently is kept alive due to popular demand.

Initial Ontology Development

  • COE COE (CmapTools Ontology Editor) is a specialized version of the CmapTools from IMHC. COE — and its CmapTools parent — is based on the idea of concept maps. A concept map is a graph diagram that shows the relationships among concepts. Concepts are connected with labeled arrows, with the relations manifesting in a downward-branching hierarchical structure. COE is an integrated suite of software tools for constructing, sharing and viewing OWL encoded ontologies based on these constructs
  • Conzilla2 is a second generation concept browser and knowledge management tool with many purposes. It can be used as a visual designer and manager of RDF classes and ontologies, since its native storage is in RDF. It also has an online collaboration server [apparently last updated in 2008]
  • has an online Flex network graph demo, which also has a neat facility for quick entry and visualization of relationships; mostly small scale; pretty cool. Does not appear to be code available anywhere
  • <New>DL-Learner is a tool for learning OWL class expressions from examples and background knowledge. It extends Inductive Logic Programming (ILP) to Description Logics and the Semantic Web. DL-Learner now has a flexible component based design, which allows to extend it easily with new learning algorithms, learning problems, reasoners, and supported background knowledge sources. A new type of supported knowledge sources are SPARQL endpoints, where DL-Learner can extract knowledge fragments, which enables learning classes even on large knowledge sources like DBpedia, and includes an OWL API reasoner interface and Web service interface.
  • DogmaModeler is a free and open source, ontology modeling tool based on ORM. The philosophy of DogmaModeler is to enable non-IT experts to model ontologies with a little or no involvement of an ontology engineer; project is quite old, but the software is still available and it may provide some insight into naive ontology development
  • Erca is a framework that eases the use of Formal and Relational Concept Analysis, a neat clustering technique. Though not strictly an ontology tool, Erca could be implemented in a work flow that allows easy import of formal contexts from CSV files, then algorithms that computes the concept lattice of the formal contexts that can be exported as dot graphs (or in JPG, PNG, EPS and SVG formats). Erca is provided as an Eclipse plug-in
  • GraphMind is a mindmap editor for Drupal. It has the basic mindmap features and some Drupal specific enhancements. There is a quick screencast about how GraphMind looks like and what is does. The Flex source is also available from Github
  • <New>H-Maps is a commercial suite of tools for building topic maps applications, consisting of a topic maps engine and server, a mapping framework for converting from legacy data, and a navigator for visualizing data. It is typically used in bioinformatics (drug discovery and research, toxicological studies, etc), engineering (support and expert systems), and for integration of hetereogeneous data. It supports the XTM 1.0 and TMAPI 1.0 specifications
  • irON using spreadsheets, via its notation and specification. Spreadsheets can be used for initial authoring, esp if the irON guidelines are followed. See further this case study of Sweet Tools in a spreadsheet using irON (commON)
  • <New>JXML2OWL API is a library for mapping XML schemas to OWL Ontologies on the JAVA platform. It creates an XSLT which transforms instances of the XML schema into instances of the OWL ontology. JXML2OWL Mapper is GUI application using the JXML2OWL API
  • MindRaider is Semantic Web outliner. It aims to connect the tradition of outline editors with emerging technologies. MindRaider mission is to organize not only the content of your hard drive but also your cognitive base and social relationships in a way that enables quick navigation, concise representation and inferencing
  • <New>Neologism is a simple web-based RDF Schema vocabulary editor and publishing system. Use it to create RDF classes and properties, which are needed to publish data on the Semantic Web. Its main goal is to dramatically reduce the time required to create, publish and modify vocabularies for the Semantic Web. It is written in PHP and built on the Drupal platform. Neologism is currently in alpha
  • <New>OCS – Ontology Creation System is software to develop ontologies in cooperative way with a graphical interface
  • RDF123 is an application and web service for converting data in simple spreadsheets to an RDF graph. Users control how the spreadsheet’s data is converted to RDF by constructing a graphical RDF123 template that specifies how each row in the spreadsheet is converted as well as metadata for the spreadsheet and its RDF translation
  • <New>ROC (Rapid Ontology Construction) is a tool that allows domain experts to quickly build a basic vocabulary for their domain, re-using existing terminology whenever possible. How this works is that the ROC tool asks the domain expert for a set of keywords that are ‘core’ terms of the domain, and then queries remote sources for concepts matching those terms. These are then presented to the user, who can select terms from the list, find relations to other terms, and expand the set of terms and relations, iteratively. The resulting vocabulary (or ‘proto-ontology’, basically a SKOS-like thesaurus) can be used as is, or can be used as input for a knowledge engineer to base a more comprehensive domain ontology on. Interface “triples-oriented,” not graphical.
  • Topincs is a Topic Map authoring software that allows groups to share their knowledge over the web. It makes use of a variety of modern technologies. The most important are Topic Maps, REST and Ajax. It consists of three components: the Wiki, the Editor, and the Server. The servier requires AMP; the Editor and Wiki are based on browser plug-ins.

Ontology Editing

  • First, see all of the Comprehensive Tools and Ontology Development listings above
  • Anzo for Excel includes an (RDFS and OWL-based) ontology editor that can be used directly within Excel. In addition to that, Anzo for Excel includes the capability to automatically generate an ontology from existing spreadsheet data, which is very useful for quick bootstrapping of an ontology
  • <New>ATop is a topic map browser and editor written in Java and supports the XTM 1.0 specification; project has not been updated since 2008
  • Hozo is an ontology visualization and development tool that brings version control constructs to group ontology development; limited to a prototype, with no online demo
  • Lexaurus Editor is for off-line creation and editing of vocabularies, taxonomies and thesauri. It supports import and export in Zthes and SKOS XML formats, and allows hierarchical / poly-hierarchical structures to be loaded for editing, or even multiple vocabularies to be loaded simultaneously, so that terms from one taxonomy can be re-used in another, using drag and drop. Not available in open source
  • Model Futures OWL Editor combines simple OWL tools, featuring UML (XMI), ErWin, thesaurus and imports. The editor is tree-based and has a “navigator” tool for traversing property and class-instance relationships. It can import XMI (the interchange format for UML) and Thesaurus Descriptor (BT-NT XML), and EXPRESS XML files. It can export to MS Word.
  • <New>OBO-Edit is an open source ontology editor written in Java. OBO-Edit is optimized for the OBO biological ontology file format. It features an easy to use editing interface, a simple but fast reasoner, and powerful search capabilities
  • <New>Onotoa is an Eclipse-based ontology editor for topic maps. It has a graphical UML-like interface, an export function for the current TMCL-draft and a XTM export
  • OntoTrack is a browsing and editing ontology authoring tool for OWL Lite. It combines a sophisticated graphical layout with mouse enabled editing features optimized for efficient navigation and manipulation of large ontologies
  • OWLViz is an attractive visual editor for OWL and is available as a Protégé plug-in
  • PoolParty is a triple store-based thesaurus management environment which uses SKOS and text extraction for tag recommendations. See further this manual, which describes more fully the system’s functionality. Also, there is a PoolParty Web service that enables a Zthes thesaurus in XML format to be uploaded and converted to SKOS (via skos:Concepts)
  • SKOSEd is a plugin for Protege 4 that allows you to create and edit thesauri (or similar artefacts) represented in the Simple Knowledge Organisation System (SKOS).
  • TemaTres is a Web application to manage controlled vocabularies, taxonomies and thesaurus. The vocabularies may be exported in Zthes, Skos, TopicMap, etc.
  • ThManager is a tool for creating and visualizing SKOS RDF vocabularies. ThManager facilitates the management of thesauri and other types of controlled vocabularies, such as taxonomies or classification schemes
  • Vitro is a general-purpose web-based ontology and instance editor with customizable public browsing. Vitro is a Java web application that runs in a Tomcat servlet container. With Vitro, you can: 1) create or load ontologies in OWL format; 2) edit instances and relationships; 3) build a public web site to display your data; and 4) search your data with Lucene. Still in somewhat early phases, with no online demos and with minimal interfaces.
  • <New>Vocab Editor is an RDF/OWL/SKOS vocabulary-diagram editor. It has both client- (Javascript) and server-side (Python) implmentations. It is open source with a demo. There is a blog (Spanish) and online sample vocabulary app editor.

Not Apparently in Active Use

  • Omnigator The Omnigator is a form-based manipulaton tool centered on Topic Maps, though it enables the loading and navigation of any conforming topic map in XTM, HyTM, LTM or RDF formats. There is a free evaluation version.
  • OntoGen is a semi-automatic and data-driven ontology editor focusing on editing of topic ontologies (a set of topics connected with different types of relations). The system combines text-mining techniques with an efficient user interface. It requires .Net.
  • OntoLight is a set of software modules for: transforming raw ontology data for several ontologies from their specific formats into a unifying light-weight ontology format, grounding the ontology and storing it into grounded ontology format, populating grounded ontologies with new instance data, and creating mappings between grounded ontologies; includes Cyc. Download no longer available. See and or
  • OWL-S-editor is an editor for the development of services in OWL-S, with graphical, WSDL and import/export support
  • ReTAX+ is an aide to help a taxonomist create a consistent taxonomy and in particular provides suggestions as to where a new entity could be placed in the taxonomy whilst retaining the integrity of the revised taxonomy (c.f., problems in ontology modelling)
  • SWOOP is a lightweight ontology editor. (Swoop is no longer under active development at mindswap. Continuing development can be found on SWOOP’s Google Code homepage at
  • WebOnto supports the browsing, creation and editing of ontologies through coarse grained and fine grained visualizations and direct manipulation.

Ontology Mapping

  • <New>The Alignment API is an API and implementation for expressing and sharing ontology alignments. The correspondences between entities (e.g., classes, objects, properties) in ontologies is called an alignment. The API provides a format for expressing alignments in a uniform way. The goal of this format is to be able to share on the web the available alignments. The format is expressed in RDF, so it is freely extensible. The Alignment API itself is a Java description of tools for accessing the common format. It defines four main interfaces (Alignment, Cell, Relation and Evaluator).
  • COMA++ is a schema and ontology matching tool with a comprehensive infrastructure. Its graphical interface supports a variety of interaction
  • ConcepTool is a system to model, analyse, verify, validate, share, combine, and reuse domain knowledge bases and ontologies, reasoning about their implication
  • <New>MapOnto is a research project aiming at discovering semantic mappings between different data models, e.g, database schemas, conceptual schemas, and ontologies. So far, it has developed tools for discovering semantic mappings between database schemas and ontologies as well as between different database schemas. The Protege plug-in is still available, but appears to be for older versions
  • MatchIT automates and facilitates schema matching and semantic mapping between different Web vocabularies. MatchIT runs as a stand-alone or plug-in Eclipse application and can be integrated with popular third party applications. MatchIT’s uses Adaptive Lexicon™ as an ontology-driven dictionary and thesaurus of English language terminology to quantify and ank the semantic similarity of concepts. It apparently is not available in open source
  • myOntology is used to produce the theoretical foundations, and deployable technology for the Wiki-based, collaborative and community-driven development and maintenance of ontologies instance data and mappings
  • OLA/OLA2 (OWL-Lite Alignment) matches ontologies written in OWL. It relies on a similarity combining all the knowledge used in entity descriptions. It also deal with one-to-many relationships and circularity in entity descriptions through a fixpoint algorithm
  • Potluck is a Web-based user interface that lets casual users—those without programming skills and data modeling expertise—mash up data themselves. Potluck is novel in its use of drag and drop for merging fields, its integration and extension of the faceted browsing paradigm for focusing on subsets of data to align, and its application of simultaneous editing for cleaning up data syntactically. Potluck also lets the user construct rich visualizations of data in-place as the user aligns and cleans up the data.
  • PRIOR+ is a generic and automatic ontology mapping tool, based on propagation theory, information retrieval technique and artificial intelligence model. The approach utilizes both linguistic and structural information of ontologies, and measures the profile similarity and structure similarity of different elements of ontologies in a vector space model (VSM).
  • <New>S-Match takes any two tree like structures (such as database schemas, classifications, lightweight ontologies) and returns a set of correspondences between those tree nodes which semantically correspond to one another.
  • Vine is a tool that allows users to perform fast mappings of terms across ontologies. It performs smart searches, can search using regular expressions, requires a minimum number of clicks to perform mappings, can be plugged into arbitrary mapping framework, is non-intrusive with mappings stored in an external file, has export to text files, and adds metadata to any mapping. See also

Not Apparently in Active Use

  • ASMOV (Automated Semantic Mapping of Ontologies with Validation) is an automatic ontology matching tool which has been designed in order to facilitate the integration of heterogeneous systems, using their data source ontologies
  • Chimaera is a software system that supports users in creating and maintaining distributed ontologies on the web. Two major functions it supports are merging multiple ontologies together and diagnosing individual or multiple ontologies
  • CMS (CROSI Mapping System) is a structure matching system that capitalizes on the rich semantics of the OWL constructs found in source ontologies and on its modular architecture that allows the system to consult external linguistic resources
  • ConRef is a service discovery system which uses ontology mapping techniques to support different user vocabularies
  • DRAGO reasons across multiple distributed ontologies interrelated by pairwise semantic mappings, with a vision of peer-to-peer mapping of many distributed ontologies on the Web. It is implemented as an extension to an open source Pellet OWL Reasoner
  • Falcon-AO (Finding, aligning and learning ontologies) is an automatic ontology matching tool that includes the three elementary matchers of String, V-Doc and GMO. In addition, it integrates a partitioner PBM to cope with large-scale ontologies
  • FOAM is the Framework for ontology alignment and mapping. It is based on heuristics (similarity) of the individual entities (concepts, relations, and instances)
  • hMAFRA (Harmonize Mapping Framework) is a set of tools supporting semantic mapping definition and data reconciliation between ontologies. The targeted formats are XSD, RDFS and KAON
  • IF-Map is an Information Flow based ontology mapping method. It is based on the theoretical grounds of logic of distributed systems and provides an automated streamlined process for generating mappings between ontologies of the same domain
  • LILY is a system matching heterogeneous ontologies. LILY extracts a semantic subgraph for each entity, then it uses both linguistic and structural information in semantic subgraphs to generate initial alignments. The system is presently in a demo version only
  • MAFRA Toolkit – the Ontology MApping FRAmework Toolkit allows users to create semantic relations between two (source and target) ontologies, and apply such relations in translating source ontology instances into target ontology instances
  • OntoEngine is a step toward allowing agents to communicate even though they use different formal languages (i.e., different ontologies). It translates data from a “source” ontology to a “target”
  • OWLS-MX is a hybrid semantic Web service matchmaker. OWLS-MX 1.0 utilizes both description logic reasoning, and token based IR similarity measures. It applies different filters to retrieve OWL-S services that are most relevant to a given query
  • RiMOM (Risk Minimization based Ontology Mapping) integrates different alignment strategies: edit-distance based strategy, vector-similarity based strategy, path-similarity based strategy, background-knowledge based strategy, and three similarity-propagation based strategies
  • semMF is a flexible framework for calculating semantic similarity between objects that are represented as arbitrary RDF graphs. The framework allows taxonomic and non-taxonomic concept matching techniques to be applied to selected object properties
  • Snoggle is a graphical, SWRL-based ontology mapper. Snoggle attempts to solve the ontology mapping problem by providing a graphical user interface (similar to which of the Microsoft Visio) to guide the process of ontology vocabulary alignment. In Snoggle, user-defined mappings can be serialized into rules, which is expressed using SWRL
  • Terminator is a tool for creating term to ontology resource mappings (documentation in Finnish).

Ontology Visualization/Analysis

Though all are not relevant, see my post from a couple of years back on large-scale RDF graph software.

  • Social network graphing tools (many covered elsewhere)
  • Cytoscape is a bioinformatics software platform for visualizing molecular interaction networks and integrating these interactions with gene expression profiles and other state data; I have also written specifically about Cytoscape’s use in UMBEL
    • RDFScape is a project that brings Semantic Web “features” to the popular Systems Biology software Cytoscape
    • NetworkAnalyzer performs analysis of biological networks and calculates network topology parameters including the diameter of a network, the average number of neighbors, and the number of connected pairs of nodes. It also computes the distributions of more complex network parameters such as node degrees, average clustering coefficients, topological coefficients, and shortest path lengths. It displays the results in diagrams, which can be saved as images or text files; used by SD
  • Graphl is a tool for collaborative editing and visualisation of graphs, representing relationships between resources or concepts of the real world. Graphl may be thought of as a visual wiki, a place where everybody can contribute to a shared repository of knowledge
  • <New>Graphviz is open source graph visualization software. It has several main graph layout programs. It also has web and interactive graphical interfaces, and auxiliary tools, libraries, and language bindings.
  • <New>GrOWL is an ontology visualizer and editor. The layout of the GrOWL graph can be defined automatically or loaded from a separate style sheet. GrOWL implements configurable filters that can transform the display by simplifying it, hiding concepts and relationships that have no descriptions associated, or perform more complex translations. Concepts can be stored in ontologies with extensive annotations to provide documentation. GrOWL shows these annotation as tooltips, and supports complex HTML and links within them. The GrOWL browser can be used inside a web browser or as a stand-alone application. When used inside a browser, it supports Javascript interaction so that it can be used as a concept chooser with implementation-defined operations.
  • igraph is a free software package for creating and manipulating undirected and directed graphs
  • Network Workbench is a very complex, comprehensive; Swiss Army Knife
  • NetworkX – Python; very clean
  • <New>OntoGraf, a Protege 4 plug-in, gives support for interactively navigating the relationships of your OWL ontologies. Various layouts are supported for automatically organizing the structure of your ontology. Different relationships are supported: subclass, individual, domain/range object properties, and equivalence. Relationships and node types can be filtered.
  • <New>OWL2Prefuse is a Java package which creats Prefuse graphs and trees from OWL files (and Jena OntModels). It takes care of converting the OWL data structure to the Prefuse datastructure. This makes it is easy for developers, to use the Prefuse graphs and trees into their Semantic Web applications.
  • <New>RDF Gravity is a tool for visualising RDF/OWL Graphs/ ontologies. RDF Gravity is implemented by using the JUNG Graph API and Jena semantic web toolkit. Its main features are:
    • Graph Visualization
    • Global and Local Filters (enabling specific views on a graph)
    • Full text Search
    • Generating views from RDQL Queries
    • Visualising multiple RDF files
  • <Newest> SKOS Reader is a SKOS browser and an HTML renderer of SKOS thesauri and terminologies that can display a SKOS file hierarchically, alphabetically, or permuted. Commercial; from Mondeca
  • Stanford Network Analysis Package (SNAP) is a general purpose network analysis and graph mining library. It is written in C++ and easily scales to massive networks with hundreds of millions of nodes
  • Social Networks Visualizer (SocNetV) is a flexible and user-friendly tool for the analysis and visualization of Social Networks. It lets you construct networks (mathematical graphs) with a few clicks on a virtual canvas or load networks of various formats (GraphViz, GraphML, Adjacency, Pajek, UCINET, etc) and modify them to suit your needs. SocNetV also offers a built-in web crawler, allowing you to automatically create networks from all links found in a given initial URL
  • Tulip may be incredibly strong
  • Springgraph component for Flex
  • VizierFX is a Flex library for drawing network graphs. The graphs are laid out using GraphViz on the server side, then passed to VizierFX to perform the rendering. The library also provides the ability to run ActionScript code in response to events on the graph, such as mousing over a node or clicking on it.
  • <New>VUE (Visual Understanding Environment) is an open source project focused on creating flexible tools for managing and integrating digital resources in support of teaching, learning and research. VUE provides a flexible visual environment for structuring, presenting, and sharing digital information.
  • <New>yEd is a diagram editor that can be used to quickly and effectively generate high-quality drawings of diagrams. It can support OWL imports.
  • <New>ZGRViewer is a graph visualizer implemented in Java and based upon the Zoomable Visual Transformation Machine. It is specifically aimed at displaying graphs expressed using the DOT language from AT&T GraphViz and processed by programs dot, neato or others such as twopi. ZGRViewer is designed to handle large graphs, and offers a zoomable user interface (ZUI), which enables smooth zooming and easy navigation in the visualized structure.

Miscellaneous Ontology Tools

  • Apolda (Automated Processing of Ontologies with Lexical Denotations for Annotation) is a plugin (processing resource) for GATE ( The Apolda processing resource (PR) annotates a document like a gazetteer, but takes the terms from an (OWL) ontology rather than from a list
  • <Newest>CA Manager supports customized workflows for semantic annotation of content. Commercial; from Mondeca
  • <New>Gloze is a XML to RDF, RDF to XML, and XSD to OWL mapping tool based on Jena; see also . See also
  • <New>Hoolet is an implementation of an OWL-DL reasoner that uses a first order prover. The ontology is translated to collection of axioms (in an obvious way based on the OWL semantics) and this collection of axioms is then given to a first order prover for consistency checking.
  • LexiLink is a tool for building, curating and managing multiple lexicons and ontologies in one enterprise-wide Web-based application. The core of the technology is based on RDF and OWL
  • mopy is the Music Ontology Python library, designed to provide easy to use python bindings for ontology terms for the creation and manipulation of music ontology data. mopy can handle information from several ontologies, including the Music Ontology, full FOAF vocab, and the timeline and chord ontologies
  • OBDA (Ontology Based Data Access) is a plugin for Protégé aimed to be a full-fledged OBDA ontology and component editor. It provides data source and mapping editors, as well as querying facilities that, in sum, allow you to design and test every aspect of an OBDA system. It supports relational data sources (RDBMS) and GLAV-like mappings. In its current beta form, it requires Protege 3.3.1, a reasoner implementing the OBDA extensions to DIG 1.1 (e.g., the DIG server for QuOnto) and Jena 2.5.5
  • <New>oBrowse is a web based ontology browser developed in java. oBrowse parses OWL files of an ontology and displays ontology in a tree view. Protege-API, JSF are used in development
  • OntoComP is a Protégé 4 plugin for completing OWL ontologies. It enables the user to check whether an OWL ontology contains “all relevant information” about the application domain, and extend the ontology appropriately if this is not the case
  • Ontology Browser is a browser created as part of the CO-ODE ( project; rather simple interface and use
  • Ontology Metrics is a web-based tool that displays statistics about a given ontology, including the expressivity of the language it is written in
  • <New>OntoLT aims at a more direct connection between ontology engineering and linguistic analysis. OntoLT is a Protégé plug-in, with which concepts (Protégé classes) and relations (Protégé slots) can be extracted automatically from linguistically annotated text collections. It provides mapping rules, defined by use of a precondition language that allow for a mapping between linguistic entities in text and class/slot candidates in Protégé. Only available for older Protégé versions
  • OntoSpec is a SWI-Prolog module, aiming at automatically generating XHTML specification from RDF-Schema or OWL ontologies
  • OWL API is a Java interface and implementation for the W3C Web Ontology Language (OWL), used to represent Semantic Web ontologies. The API is focused towards OWL Lite and OWL DL and offers an interface to inference engines and validation functionality
  • OWL Module Extractor is a Web service that extracts a module for a given set of terms from an ontology. It is based on an implementation of locality-based modules that is part of the OWL API.
  • OWL Syntax Converter is an online tool for converting ontologies between different formats, including several OWL syntaxes, RDF/XML, KRSS
  • OWL Verbalizer is an on-line tool that verbalizes OWL ontologies in (controlled) English
  • OwlSight is an OWL ontology browser that runs in any modern web browser; it’s developed with Google Web Toolkit and uses Gwt-Ext, as well as OWL-API. OwlSight is the client component and uses Pellet as its OWL reasoner
  • Pellint is an open source lint tool for Pellet which flags and (optionally) repairs modeling constructs that are known to cause performance problems. Pellint recognizes several patterns at both the axiom and ontology level.
  • PROMPT is a tab plug-in for Protégé is for managing multiple ontologies by comparing versions of the same ontology, moving frames between included and including project, merging two ontologies into one, or extracting a part of an ontology
  • <New>ReDeFer is a compendium of RDF-aware utilities organised in a set of packages: RDF2HTML+RDFa: render a piece of RDF/XML as HTML+RDFa; XSD2OWL: transform an XML Schema into an OWL Ontology; CS2OWL: transform a MPEG-7 Classification Scheme into an OWL Ontology; XML2RDF: transform a piece of XML into RDF; and RDF2SVG: render a piece of RDF/XML as a SVG showing the corresponding graph
  • SegmentationApp is a Java application that segments a given ontology according to the approach described in “Web Ontology Segmentation: Analysis, Classification and Use” (
  • SETH is a software effort to deeply integrate Python with Web Ontology Language (OWL-DL dialect). The idea is to import ontologies directly into the programming context so that its classes are usable alongside standard Python classes
  • SKOS2GenTax is an online tool that converts hierarchical classifications available in the W3C SKOS (Simple Knowledge Organization Systems) format into RDF-S or OWL ontologies
  • SpecGen (v5) is an ontology specification generator tool. It’s written in Python using Redland RDF library and licensed under the MIT license
  • Text2Onto is a framework for ontology learning from textual resources that extends and re-engineers an earlier framework developed by the same group (TextToOnto). Text2Onto offers three main features: it represents the learned knowledge at a metalevel by instantiating the modelling primitives of a Probabilistic Ontology Model (POM), thus remaining independent from a specific target language while allowing the translation of the instantiated primitives
  • Thea is a Prolog library for generating and manipulating OWL (Web Ontology Language) content. Thea OWL parser uses SWI-Prolog’s Semantic Web library for parsing RDF/XML serialisations of OWL documents into RDF triples and then it builds a representation of the OWL ontology
  • TONES Ontology Repository is primarily designed to be a central location for ontologies that might be of use to tools developers for testing purposes; it is part of the TONES project
  • Visual Ontology Manager (VOM) is a family of tools enables UML-based visual construction of component-based ontologies for use in collaborative applications and interoperability solutions.
  • Web Ontology Manager is a lightweight, Web-based tool using J2EE for managing ontologies expressed in Web Ontology Language (OWL). It enables developers to browse or search the ontologies registered with the system by class or property names. In addition, they can submit a new ontology file
  • RDF evoc (external vocabulary importer) is an RDF external vocabulary importer module (evoc) for Drupal caches any external RDF vocabulary and provides properties to be mapped to CCK fields, node title and body. This module requires the RDF and the SPARQL modules.

Not Apparently in Active Use

  • ActiveOntology is a library, written in Ruby, for easy manipulation of RDF and RDF-Schema models, thru a dynamic DSL based on Ruby idiom
  • Almo is an ontology-based workflow engine in Java supporting the ARTEMIS project; part of the OntoWare initiative
  • ClassAKT is a text classification web service for classifying documents according to the ACM Computing Classification System
  • Elmo provides a simple API to access ontology oriented data inside a Sesame RDF repository. The domain model is simplified into independent concerns that are composed together for multi-dimensional, inter-operating, or integrated applications
  • ExtrAKT is a tool for extracting ontologies from Prolog knowledge bases.
  • F-Life is a tool for analysing and maintaining life-cycle patterns in ontology development.
  • Foxtrot is a recommender system which represents user profiles in ontological terms, allowing inference, bootstrapping and profile visualization.
  • HyperDAML creates an HTML representation of OWL content to enable hyperlinking to specific objects, properties, etc.
  • LinKFactory is an ontology management tool, it provides an effective and user-friendly way to create, maintain and extend extensive multilingual terminology systems and ontologies (English, Spanish, French, etc.). It is designed to build, manage and maintain large, complex, language independent ontologies.
  • LSW – the Lisp semantic Web toolkit enables OWL ontologies to be visualized. It was written by Alan Ruttenberg
  • OntoClassify is a system for scalable classification of text into large topic ontologies currently including DMoz and Inspec. The system is available as Web service. The software runs under Windows platform.
  • Ontodella is a Prolog HTTP server for category projection and semantic linking
  • OntoWeaver is an ontology-based approach to Web sites, which provides high level support for web site design and development
  • OWLLib is a PHP library for accessing OWL files. OWL is standard for storing semantic information
  • pOWL is a Semantic Web development platform for ontologies in PHP. pOWL consists of a number of components, including RAP
  • ROWL is the Rule Extension of OWL; it is from the Mobile Commerce Lab in the School of Computer Science at Carnegie Mellon University
  • Semantic Net Generator is a utlity for generating Topic Maps automatically from different data sources by using rules definitions specified with Jelly XML syntax. This Java library provides Jelly tags to access and modify data sources (also RDF) to create a semantic network
  • SMORE is OWL markup for HTML pages. SMORE integrates the SWOOP ontology browser, providing a clear and consistent way to find and view Classes and Properties, complete with search functionality
  • SOBOLEO is a system for Web-based collaboration to create SKOS taxonomies and ontologies and to annotate various Web resources using them
  • SOFA is a Java API for modeling ontologies and Knowledge Bases in ontology and Semantic Web applications. It provides a simple, abstract and language neutral ontology object model, inferencing mechanism and representation of the model with OWL, DAML+OIL and RDFS languages; from
  • WebScripter is a tool that enables ordinary users to easily and quickly assemble reports extracting and fusing information from multiple, heterogeneous DAMLized Web sources.

Posted by AI3's author, Mike Bergman Posted on August 23, 2010 at 12:28 am in Ontologies, Open Source, Semantic Web Tools | Comments (6)
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Posted:August 16, 2010

Contrasted with Some Observations on Linked Data

At the SemTech conference earlier this summer there was a kind of vuvuzela-like buzzing in the background. And, like the World Cup games on television, in play at the same time as the conference, I found the droning to be just as irritating.

That droning was a combination of the sense of righteousness in the superiority of linked data matched with a reprise of the “chicken-and-egg” argument that plagued the early years of semantic Web advocacy [1]. I think both of these premises are misplaced. So, while I have been a fan and explicator of linked data for some time, I do not worship at its altar [2]. And, for those that do, this post argues for a greater sense of ecumenism.

My main points are not against linked data. I think it a very useful technique and good (if not best) practice in many circumstances. But my main points get at whether linked data is an objective in itself. By making it such, I argue our eye misses the ball. And, in so doing, we miss making the connection with meaningful, interoperable information, which should be our true objective. We need to look elsewhere than linked data for root causes.

Observation #1: What Problem Are We Solving?

When I began this blog more than five years ago — and when I left my career in population genetics nearly three decades before that — I did so because of my belief in the value of information to confer adaptive advantage. My perspective then, and my perspective now, was that adaptive information through genetics and evolution was being uniquely supplanted within the human species. This change has occurred because humanity is able to record and carry forward all information gained in its experiences.

Adaptive innovations from writing to bulk printing to now electronic form uniquely position the human species to both record its past and anticipate its future. We no longer are limited to evolution and genetic information encoded in surviving offspring to determine what information is retained and moves forward. Now, all information can be retained. Further, we can combine and connect that information in ways that break to smithereens the biological limits of other species.

Yet, despite the electronic volumes and the potentials, chaos and isolated content silos have characterized humanity’s first half century of experience with digital information. I have spoken before about how we have been steadily climbing the data federation pyramid, with Internet technologies and the Web being prime factors for doing so. Now, with a compelling data model in RDF and standards for how we can relate any type of information meaningfully, we also have the means for making sense of it. And connecting it. And learning and adapting from it.

And, so, there is the answer to the rhetorical question: The problem we are solving is to meaningfully connect information. For, without those meaningful connections and recombinations, none of that information confers adaptive advantage.

Observation #2: The Problem is Not A Lack of Consumable Data

One of the “chicken-and-egg” premises in the linked data community is there needs to be more linked data exposed before some threshold to trigger the network effect occurs. This attitude, I suspect, is one of the reasons why hosannas are always forthcoming each time some outfit announces they have posted another chunk of triples to the Web.

Fred Giasson and I earlier tackled that issue with When Linked Data Rules Fail regarding some information published for and the New York Times. Our observations on the lack of standards for linked data quality proved to be quite controversial. Rehashing that piece is not my objective here.

What is my objective is to hammer home that we do not need linked data in order to have data available to consume. Far from it. Though linked data volumes have been growing, I actually suspect that its growth has been slower than data availability in toto. On the Web alone we have searchable deep Web databases, JSON, XML, microformats, RSS feeds, Google snippets, yada, yada, all in a veritable deluge of formats, contents and contexts. We are having a hard time inventing the next 1000-fold description beyond zettabyte and yottabyte to even describe this deluge [3].

There is absolutely no voice or observer anywhere that is saying, “We need linked data in order to have data to consume.” Quite the opposite. The reality is we are drowning in the stuff.

Furthermore, when one dissects what most of all of this data is about, it is about ways to describe things. Or, put another way, most all data is not schema nor descriptions of conceptual relationships, but making records available, with attributes and their values used to describe those records. Where is a business located? What political party does a politician belong to? How tall are you? What is the population of Hungary?

These are simple constructs with simple key-value pair ways to describe and convey them. This very simplicity is one reason why naïve data structs or simple data models like JSON or XML have proven so popular [4]. It is one of the reasons why the so-called NoSQL databases have also been growing in popularity. What we have are lots of atomic facts, located everywhere, and representable with very simple key-value structures.

While having such information available in linked data form makes it easier for agents to consume it, that extra publishing burden is by no means necessary. There are plenty of ways to consume that data — without loss of information — in non-linked data form. In fact, that is how the overwhelming percentage of such data is expressed today. This non-linked data is also often easy to understand.

What is important is that the data be available electronically with a description of what the records contain. But that hurdle is met in many, many different ways and from many, many sources without any reference whatsoever to linked data. I submit that any form of desirable data available on the Web can be readily consumed without recourse to linked data principles.

Observation #3: An Interoperable Data Model Does Not Require a Single Transmittal Format

The real advantage of RDF is the simplicity of its data model, which can be extended and augmented to express vocabularies and relationships of any nature. As I have stated before, that makes RDF like a universal solvent for any extant data structure, form or schema.

What I find perplexing, however, is how this strength somehow gets translated into a parallel belief that such a flexible data model is also the best means for transmitting data. As noted, most transmitted data can be represented through simple key-value pairs. Sure, at some point one needs to model the structural assumptions of the data model from the supplying publisher, but that complexity need not burden the actual transmitted form. So long as schema can be captured and modeled at the receiving end, data record transmittal can be made quite a bit simpler.

Under this mindset RDF provides the internal (canonical) data model. Prior to that, format and other converters can be used to consume the source data in its native form. A generalized representation for how this can work is shown in this diagram using Structured DynamicsstructWSF Web services framework middleware as the mediating layer:

Of course, if the source data is already in linked data form with understood concepts, relationships and semantics, much of this conversion overhead can be bypassed. If available, that is a good thing.

But it is not a required or necessary thing. Insistence on publishing data in certain forms suffers from the same narrowness as cultural or religious zealotry. Why certain publishers or authors prefer different data formats has a diversity of answers. Reasons can range from what is tried and familiar to available toolsets or even what is trendy, as one might argue linked data is in some circles today.There are literally scores of off-the-shelf “RDFizers” for converting native and simple data structs into RDF form. New converters are readily written.

Adaptive systems, by definition, do not require wholesale changes to existing practices and do not require effort where none is warranted. By posing the challenge as a “chicken-and-egg” one where publishers themselves must undertake a change in their existing practices to conform, or else they fail the “linked data threshold”, advocates are ensuring failure. There is plenty of useful structured data to consume already.

Accessible structured data, properly characterized (see below), should be our root interest; not whether that data has been published as linked data per se.

Observation #4: A Technique Can Not Carry the Burden of Usefulness or Interoperability

Linked data is nothing more than some techniques for publishing Web-accessible data using the RDF data model. Some have tried to use the concept of linked data as a replacement for the idea of the semantic Web, and some have recently tried to re-define linked data as not requiring RDF [5]. Yet the real issue with all of these attempts — correct or not, and a fact of linked data since first formulated by Tim Berners-Lee — is that a technique alone can not carry the burden of usefulness or interoperability.

Despite billions of triples now available, we in fact see little actual use or consumption of linked data, except in the life science domain. Indeed, a new workshop by the research community called COLD (Consuming Linked Data) has been set up for the upcoming ISWC conference to look into the very reasons why this lack of usage may be occurring [6].

It will be interesting to monitor what comes out of that workshop, but I have my own views as to what might be going on here. A number of factors, applicable frankly to any data, must be layered on top of linked data techniques in order for it to be useful:

  • Context and coherence (see below)
  • Curation and quality control (where provenance is used as the proxy), and
  • Up-to-date and timely.

These requirements apply to any data ranging from Census CSV files to Google search results. But because relationships can also be more readily asserted with linked data, these requirements are even greater for it.

It is not surprising that the life sciences have seen more uptake of linked data. That community has keen experience with curation, and the quality and linkages asserted there are much superior to other areas of linked data [7].

In other linked data areas, it is really in limited pockets such as FactForge from Ontotext or curated forms of Wikipedia by the likes of Freebase that we see the most use and uptake. There is no substitute for consistency and quality control.

It is really in this area of “publish it and they will come” that we see one of the threads of parochialism in the linked data community. You can publish it and they still will not come. And, like any data, they will not come because the quality is poor or the linkages are wrong.

As a technique for making data available, linked data is thus nothing more than a foot soldier in the campaign to make information meaningful. Elevating it above its pay grade sets the wrong target and causes us to lose focus for what is really important.

Observation #5: 50% of Linked Data is Missing (that is, the Linking part)

There is another strange phenomenon in the linked data movement: the almost total disregard for the linking part. Sure data is getting published as triples with dereferencable URIs, but where are the links?

At most, what we are seeing is owl:sameAs assertions and a few others [8]. Not only does this miss the whole point of linked data, but one can question whether equivalence assertions are correct in many instances [9].

For a couple of years now I have been arguing that the central gap in linked data has been the absence of context and coherence. By context I mean the use of reference structures to help place and frame what content is about. By coherence I mean that those contextual references make internal and logical sense, that they represent a consistent world view. Both require a richer use of links to concepts and subjects describing the semantics of the content.

It is precisely through these kinds of links that data from disparate sources and with different frames of reference can be meaningfully related to other data. This is the essence of the semantic Web and the purported purpose of linked data. And it is exactly these areas in which linked data is presently found most lacking.

Of course, these questions are not the sole challenge of linked data. They are the essential challenge in any attempt to connect or interoperate structured data within information systems. So, while linked data is ostensibly designed from the get-go to fulfill these aims, any data that can find meaning outside of its native silo must also be placed into context in a coherent manner. The unique disappointment for much linked data is its failure to provide these contexts despite its design.

Observation #6: Pluralism is a Reality; Embrace It

Yet, having said all of this, Structured Dynamics is still committed to linked data. We present our information as such, and provide great tools for producing and consuming it. We have made it one of the seven foundations to our technology stack and methodology.

But we live in a pluralistic data world. There are reasons and roles for the multitude of popular structured data formats that presently exist. This inherent diversity is a fact in any real-world data context. Thus, we have not met a form of structured data that we didn’t like, especially if it is accompanied with metadata that puts the data into coherent context. It is a major reason why we developed the irON (instance record and object notation) non-RDF vocabulary to provide a bridge from such forms to RDF. irON clearly shows that entities can be usefully described and consumed in either RDF or non-RDF serialized forms.

Attitudes that dismiss non-linked data forms or arrogantly insist that publishers adhere to linked data practices are anything but pluralistic. They are parochial and short-sighted and are contributing, in part, to keeping the semantic Web from going mainstream.

Adoption requires simplicity. The simplest way to encourage the greater interoperability of data is to leverage existing assets in their native form, with encouragement for minor enhancements to add descriptive metadata for what the content is about. Embracing such an ecumenical attitude makes all publishers potentially valuable contributors to a better information future. It will also nearly instantaneously widen the tools base available for the common objective of interoperability.

Parochialism and Root Cause Analysis

Linked data is a good thing, but not an ultimate thing. By making linked data an objective in itself we unduly raise publishing thresholds; we set our sights below the real problem to be solved; and we risk diluting the understanding of RDF from its natural role as a flexible and adaptive data model. Paradoxically, too much parochial insistence on linked data may undercut its adoption and the realization of the overall semantic objective.

Root cause analysis for what it takes to achieve meaningful, interoperable information suggests that describing source content in terms of what it is about is the pivotal factor. Moreover, those contexts should be shared to aid interoperability. Whichever organizations do an excellent job of providing context and coherent linkages will be the go-to ones for data consumers. As we have seen to date, merely publishing linked data triples does not meet this test.

I have heard some state that first you celebrate linked data and its growing quantity, and then hope that the quality improves. This sentiment holds if indeed the community moves on to the questions of quality and relevance. The time for that transition is now. And, oh, by the way, as long as we are broadening our horizons, let’s also celebrate properly characterized structured data no matter what its form. Pluralism is part of the tao to the meaning of information.

[1] See, for example, J.A. Hendler, 2008. “Web 3.0: Chicken Farms on the Semantic Web,” Computer, January 2008, pp. 106-108. See While I can buy Hendler’s arguments about commercial tool vendors holding off major investments until the market is sizable, I think we can also see via listings like Sweet Tools that a lack of tools is not in itself limiting.
[2] An earlier treatment of this subject from a different perspective is M.K. Bergman, 2010. “The Bipolar Disorder of Linked Data,” AI3:::Adaptive Information blog, April 28, 2010.
[3] So far only prefixes for units up to 10^24 (“yotta”) have names; for 10^27, a student campaign on Facebook is proposing “hellabyte” (North California slang for “a whole lot of”) to get adopted by science bodies. See
[4] One of more popular posts on this blog has been, M.K. Bergman, 2009. “‘Structs’: Naïve Data Formats and the ABox,” AI3:::Adaptive Information blog, January 22, 2009.
[5] See, for example, the recent history on the linked data entry on Wikipedia or the assertions by Kingsley Idehen regarding entity attribute values (EAV) (see, for example, this blog post.)
[6] See further the 1st International Workshop on Consuming Linked Data (COLD 2010), at the 9th International Semantic Web Conference (ISWC 2010), November 8, 2010, Shanghai, China.
[7] For example, in the early years of GenBank, some claimed that annotations of gene sequences due to things like BLAST analyses may have had as high as 30% to 70% error rates due to propagation of initially mislabeled sequences. In part, the whole field of bioinformatics was formed to deal with issues of data quality and curation (in addition to analytics).
[8] See, for example: Harry Halpin, 2009. “A Query-Driven Characterization of Linked Data,” paper presented at the Linked Data on the Web (LDOW) 2009 Workshop, April 20, 2009, Madrid, Spain, see; Prateek Jain, Pascal Hitzler, Peter Z. Yehy, Kunal Vermay and Amit P. Shet, 2010. “Linked Data is Merely More Data,” in Dan Brickley, Vinay K. Chaudhri, Harry Halpin, and Deborah McGuinness, Linked Data Meets Artificial Intelligence, Technical Report SS-10-07, AAAI Press, Menlo Park, California, 2010, pp. 82-86., see; among others.
[9] Harry Halpin and Patrick J. Hayes, 2010. “When owl:sameAs isn’t the Same: An Analysis of Identity Links on the Semantic Web,” presented at LDOW 2010, April 27th, 2010, Raleigh, North Carolina. See

Posted by AI3's author, Mike Bergman Posted on August 16, 2010 at 12:58 am in Adaptive Innovation, irON, Linked Data, Semantic Web | Comments (1)
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Posted:August 9, 2010

Ontologies are the structural frameworks for organizing information on the semantic Web and within semantic enterprises. They provide unique benefits in discovery, flexible access, and information integration due to their inherent connectedness; that is, their ability to represent conceptual relationships. Ontologies can be layered on top of existing information assets, which means they are an enhancement and not a displacement for prior investments. And ontologies may be developed and matured incrementally, which means their adoption may be cost-effective as benefits become evident [1].

What Is an Ontology?

Ontology may be one of the more daunting terms for those exposed for the first time to semantic technologies. Not only is the word long and without common antecedents, but it is also a term that has widely divergent use and understanding within the community. It can be argued that this not-so-little word is one of the barriers to mainstream understanding of the semantic Web.

The root of the term is the Greek ontos, or being or the nature of things. Literally — and in classical philosophy — ontology was used in relation to the study of the nature of being or the world, the nature of existence. Tom Gruber, among others, made the term popular in relation to computer science and artificial intelligence about 15 years ago when he defined ontology as a “formal specification of a conceptualization.”

Much like taxonomies or relational database schema, ontologies work to organize information. No matter what the domain or scope, an ontology is a description of a world view. That view might be limited and miniscule, or it might be global and expansive. However, unlike those alternative hierarchical views of concepts such as taxonomies, ontologies often have a linked or networked “graph” structure. Multiple things can be related to other things, all in a potentially multi-way series of relationships.

Example Taxonomy Structure Example Ontology Structure
A distinguishing characteristic of ontologies compared to conventional hierarchical structures is their degree
of connectedness, their ability to model coherent, linked relationships

Ontologies supply the structure for relating information to other information in the semantic Web or the linked data realm. Ontologies thus provide a similar role for the organization of data that is provided by relational data schema. Because of this structural role, ontologies are pivotal to the coherence and interoperability of interconnected data.

When one uses the idea of “world view” as synonomous with an ontology, it is not meant to be cosmic, but simply a way to convey how a given domain or problem area can be described. One group might choose to describe and organize, say, automobiles, by color; another might choose body styles such as pick-ups or sedans; or still another might use brands such as Honda and Ford. None of these views is inherently “right” (indeed multiples might be combined in a given ontology), but each represents a particular way — a “world view” — of looking at the domain.

Though there is much latitude in how a given domain might be described, there are both good ontology practices and bad ones. We offer some views as to what constitutes good ontology design and practice in the concluding section.

What Are Its Benefits?

A good ontology offers a composite suite of benefits not available to taxonomies, relational database schema, or other standard ways to structure information. Among these benefits are:

  • Coherent navigation by enabling the movement from concept to concept in the ontology structure
  • Flexible entry points because any specific perspective in the ontology can be traced and related to all of its associated concepts; there is no set structure or manner for interacting with the ontology
  • Connections that highlight related information and aid and prompt discovery without requiring prior knowledge of the domain or its terminology
  • Ability to represent any form of information, including unstructured (say, documents or text), semi-structured (say, XML or Web pages) and structured (say, conventional databases) data
  • Inferencing, whereby by specifying one concept (say, mammals) one knows that we are also referring to a related concept (say, that mammals are a kind of animal)
  • Concept matching, which means that even though we may describe things somewhat differently, we can still match to the same idea (such as glad or happy both referring to the concept of a pleasant state of mind)
  • Thus, this means that we can also integrate external content by proper matching and mapping of these concepts
  • A framework for disambiguation by nature of the matching and analysis of concepts and instances in the ontology graph, and
  • Reasoning, which is the ability to use the coherence and structure itself to inform questions of relatedness or to answer questions.

How Are Ontologies Used?

The relationship structure underlying an ontology provides an excellent vehicle for discovery and linkages. “Swimming through” this relationship graph is the basis of the Concept Explorer (also known as the Relation Browser) and similar widgets.

The most prevalent use of ontologies at present is in semantic search. Semantic search has benefits over conventional search in terms of being able to make inferences and matches not available to standard keyword retrieval.

The relationship structure also is a powerful and more general and more nuanced way to organize information. Concepts can relate to other concepts through a richness of vocabulary. Such predicates might capture subsumption, precedence, parts of relationships (mereology), preferences, or importances along virtually any metric. This richness of expression and relationships can also be built incrementally over time, allowing ontologies to grow and develop in sophistication and use as desired.

The pinnacle application for ontologies, therefore, is as coherent reference structures whose purpose is to help map and integrate other structures and information. Given the huge heterogeneity of information both within and without organizations, the use of ontologies as integration frameworks will likely emerge as their most valuable use.

What Makes for a Good Ontology?

Good ontology practice has aspects both in terms of scope and in terms of construction.

Scope Considerations

Here are some scoping and design questions that we believe should be answered in the positive in order for an ontology to meet good practice standards:

  • Does the ontology provide balanced coverage of the subject domain? This question gets at the issue of properly scoping and bounding the subject coverage of the ontology. It also means that the breadth and depth of the coverage is roughly equivalent across its scope
  • Does the ontology embed its domain coverage into a proper context? A major strength of ontologies is their potential ability to interoperate with other ontologies. Re-using existing and well-accepted vocabularies and including concepts in the subject ontology that aid such connections is good practice. The ontology should also have sufficient reference structure for guiding the assignment of what content “is about”
  • Are the relationships in the ontology coherent? The essence of coherence is that it is a state of logical, consistent connections, a logical framework for integrating diverse elements in an intelligent way. So while context supplies a reference structure, coherence means that the structure makes sense. Is the hip bone connected to the thigh bone, or is the skeleton incorrect?
  • Has the ontology been well constructed according to good practice? See next.

If these questions can be answered affirmatively, then we would deem the ontology ready for production-grade use.

Fundamental to the whole concept of coherence is the fact that experts and practitioners within domains have been looking at the questions of relationships, structure, language and meaning for decades. Though perhaps today we now finally have a broad useful data and logic model in RDF, the fact remains that massive time and effort has already been expended to codify some of these understandings in various ways and at various levels of completeness and scope. Good practice also means, therefore, that maximum leverage is made to springboard ontologies from existing structural and vocabulary assets.

And, because good ontologies also embrace the open world approach, working toward these desired end states can also be incremental. Thus, in the face of common budget or deadline constraints, it is possible initially to scope domains as smaller or to provide less coverage in depth or to use a small set of predicates, all the while still achieving productive use of the ontology. Then, over time, the scope can be expanded incrementally.

Construction Considerations

To achieve their purposes, ontologies must be both human-readable and machine-processable. Also, because they represent conceptual structures, they must be built with a certain composition.

Good ontologies therefore are constructed such that they have:

  • Concept definitions – the matching and alignment of things is done on the basis of concepts (not simply labels) which means each concept must be defined
  • A preferred label that is used for human readable purposes and in user interfaces
  • A “semset” – which means a series of alternate labels and terms to describe the concept. These alternatives include true synonyms, but may also be more expansive and include jargon, slang, acronyms or alternative terms that usage suggests refers to the same concept
  • Clearly defined relationships (also known as properties, attributes, or predicates) for relating two things to one another
  • All of which is written in a machine-processable language such as OWL or RDF Schema (among others).

In the case of ontology-driven applications using adaptive ontologies, there are also additional instructions contained in the system (often via administrative ontologies) that tell the system which types of widgets need to be invoked for different data types and attributes. This is different than the standard conceptual schema, but is nonetheless essential to how such applications are designed.

[1] This posting was at the request of a couple of Structured Dynamics‘ customers that desired a way to describe ontologies to non-technical management. For a more in depth treatment, see M.K. Bergman, 2007. “An Intrepid Guide to Ontologies,” AI3:::Adaptive Information blog, May 16, 2007.
Posted:August 2, 2010

Citizen Dan
Discover and Play with this Demo of the Open Semantic Framework

Today, Structured Dynamics is pleased to make its Citizen Dan application available for public viewing, play and downloading for the first time.

Citizen Dan is a free, open source system available to any community and its citizens to measure and track indicators of local well being. It can be branded and themed for local needs. It is under active development by Structured Dynamics with support from a number of innovative cities.

Citizen Dan is an exemplar instance of Structured Dynamics’ open semantic framework (OSF), a generalized framework for deploying semantic platforms for any domain.  By changing its guiding ontologies and source content and data, what appears for Citizen Dan can be adopted for virtually any subject area.

As configured, the Citizen Dan OSF instance is a:

  • Appliance for slicing-and-dicing and analyzing data specific to local community indicators
  • Framework for dynamically navigating, interacting with, or browsing data and concepts
  • Means to visualize local data over time or by neighborhood
  • Meeting place for the public to upload and share local data and information
  • Web data portal that can be individually tailored by any local community
  • Potential node in a global network of communities across which to compare indicators of community well-being.

Citizen Dan’s information sources may include Census data, the Web, real-time feeds, government datasets, municipal government information systems, or crowdsourced data. Information can range from standard structured data to local narratives, including from minutes and reports, contributed stories, blogs or news outlets. The ‘raw’ input data can come in essentially any format, which is then converted to a standard form with consistent semantics.

Text and narratives and the concepts and entities they describe are integrally linked into the system via information extraction and tagging. All ingested information, whether structured or text sources, with their semantics, can be exported in multiple formats. A standard organizing schema, also open source and extensible or modifiable by all users, is provided via the optional MUNI ontology (with vocabulary details in development here), being developed expressly for Citizen Dan and its community indicator system purposes.

All of the community information contained within a Citizen Dan instance is available as linked data.

Overview of Features

Here are the main components or widgets to this Citizen Dan demo:

  • Concept Explorer — this Flex widget (also called the Relation Browser) is a dynamic navigator of the concept space (ontology) that is used to organize the content on the instance. Clicking on a bubble causes it to assume the central position in the diagram, with all of its connecting concepts shown. Clicking on a branch concept then causes that new node to assume the central position, enabling one to “swim through” the overall concept graph. For this instance of Citizen Dan, the MUNI ontology is used; a diagram shows the full graph of the MUNI structure. See further the concept explorer’s technical documentation
  • Story Viewer — any type of text content (such as stories, blog posts, news articles, local government reports, city council minutes, etc.) can be submitted to the system. This content is then tagged using the scones system (subject concepts or named entities), which then provides the basis for linking the content with concepts and other data. The story viewer is a Flex widget that highlights these tags in the content and allows searches for related content based on selected tags. See further the story viewer’s technical documentation
  • Map Viewer — the map viewer is a Flex widget that presents layered views of different geographic areas. The title bar of the viewer allows different layers to be turned on and off. Clicking on various geographic areas can invoke specific data and dashboard views. See further the map viewer’s technical documentation
  • Charting Widgets — the system provides a variety of charting options for numeric data, including pie, line and bar charts. These can be called directly or sprinkled amongst other widgets based on a dashboard specification (see below)
  • Filter Component — the filter, or browse, component provides the ability to slice-and-dice the information space by a choice of dataset, type of data or data attribute. These slices then become filter selections which can be persisted across various visualizations or exports. See further the browse component’s technical documentation
  • Search Component — this component provides full-text, faceted search across all content in the system; it may be used in conjunction with the filtering above to restrict the search space to the current slice. See further the search tool’s technical documentation
  • Dashboard Viewer — a dashboard is a particular layout of one or more visualization widgets and a set (or not) of content filtering conditions to be displayed on a canvas. Dashboard views are created in the workbench (see next) and given a persistent name for invoking and use at any other location in the application
  • Workbench — this rather complex component is generally intended to be limited to site administrators. Via the workbench, records and datasets and attributes may be selected, and then particular views or widgets obtained. When no selections are made in the left-hand panel, all are selected by default. Then, in the records viewer (middle upper), either records or attributes are selected. For each attribute (column), a new display widget appears. All display widgets interact (a selection in one reflects in the others). The nature of the data type or attribute selected determines which available widgets are available to display it; sometimes there are multiples which can be selected via the lower left dropdown list in any given display panel. These various display widgets may then be selected for a nameable layout as a persistent dashboard view (functionality not shown in this public demo)
  • Exporter — the exporter component appears in multiple locations across the appliance, either as a tab option (e.g., Filter component) or as a dropdown list to the lower right of many screens. A variety (and growing!) number of export formats are available. When it appears as a dropdown list, the export is limited to the currently active slice. When invoked via tab, more export selection options are available. See further the technical documentation for this component

Limitations of the Online Demo

A number of other tools are available to admins in the actual appliance, but are not exposed in the demo:

  • Importer — like the exporter, there are a variety of formats supported for ingesting data or content into the system. Prominent ones include spreadsheets (CSV), XML and JSON. The irON notation is especially well suited for dataset staging for ingest. At import time, datasets can also be appended or merged. See further the technical documentation for this component
  • Dataset Submission and Management — new datasets can be defined, updated, deleted, appended and granted various access rights and permissions, including to the granularity of individual components or tools. For example, see further this technical documentation
  • Records Manager — every dataset can have its records managed via so-called CRUD rights. Depending on the dataset permissions, a given user may or may not see these tools. See further the technical documentation for each of these create read update delete tools.

In addition, it is not possible in the demo to save persistent dashboard views or submit stories or documents for tagging, nor to register as a user or view the admin portions of the Drupal instance.

Sample Data and Content in the Demo

The sample data and content in the demo is for the Iowa City (IA) metropolitan statistical area. This area embraces two counties (Johnson and Washington) and the census tracts and townships that comprise them, and about two dozen cities. Two of the notable cities are Iowa City itself, home of the University of Iowa, and Coralville, where Structured Dynamics, the developer of Citizen Dan and the open semantic framework (OSF), is headquartered.

The text content on this site is drawn from Wikipedia articles dealing with this area. About 30 stories are included.

The data content on the site is drawn from US Census Bureau data. Shape files for the various geographic areas were obtained from here, and the actual datasets by geographic area can be obtained from here.

An Instance of the Open Semantic Framework

Citizen Dan is an exemplar instance of Structured Dynamics’ open semantic framework (OSF), a generalized framework for deploying semantic platforms for specific domains.

OSF is a combination of a layered architecture and modular software. Most of the individual open source software products developed by Structured Dynamics and available on the OpenStructs site are components within the open semantic framework. These include:

A Part of the ‘Total Open Solution

The software that makes up the Citizen Dan appliance is one of the four legs that provide a stable, open source solution. These four legs are software, structure, methods and documentation. When all four are provided, we can term this a total open solution.

For Citizen Dan, the complements to this software are:

  • MUNI ontology, which provides the structure specification upon which the software runs, and
  • DocWiki (with its TechWiki subset of technical documentation) that provides the accompanying knowledge base of methods, best practices and other guidance.

In its entirety, the total open solution amounts to a form of capacity building for the enterprise.

The Potential for a Citizen Dan Network

Inherent in the design and architecture of Citizen Dan is the potential for each instance (single installation) to act as a node in a distributed network of nodes across the Web. Via the structWSF Web service endpoints and appropriate dataset permissions, it is possible for any city in the Citizen Dan network to share (or not) any or all of its data with other cities.

This collaboration aspect has been “baked into the cake” from Day One. The system also supports differential access, rights and roles by dataset and Web service. Thus, city staffs across multiple communities could share data differently than what is provided to the general public.

Since all data management aspects of each Citizen Dan instance is also oriented around datasets, expansion to a network mode is quite straightforward.

How to Get the System

The Citizen Dan appliance is based on the Drupal content management system, which means any community can easily theme or add to the functionality of the system with any of the available 6500 open source modules that extend the basic Drupal functionality.

All other components, including the multiple third-party ones, are also open source.

To install Citizen Dan for your own use, you need to:

  1. Download and install all of the software components. You may also want to check out the OSF discussion forum for tips and ideas about alternative configuration options
  2. Install a baseline vocabulary. In the case of Citizen Dan, this is the MUNI ontology. MUNI is imminent for public release. Please contact the project if you need an early copy
  3. Install your own datasets. You may want to inspect the sample Citizen Dan datasets and learn more about the irON notation, especially its commON (spreadsheet) use case.

(Note: there will also be some more updates in August, including the MUNI release.)

For questions and additional info, please consult the TechWiki or the OpenStructs community site.

Finally, please contact us if you’d like to learn more about the project, investigate funding or sponsorship opportunities, or contribute to development. We’d welcome your involvement!