TAXONOMY

There are many systems (the traditional ones, like libraries and documentation centres; and the more new ones with its origin in the net) in order to class and to put into categories information.

Within the most traditional methods we can name: CDU, MARC, LCC/LCSH, DDC, IFLA y Bibtex

With the boom of Internet, the most important proposal is the well-known Dubline Core. Although the Open Archive Initiative deserves a special mention.

As well as these systems based on the notion of methadata, other ways of classifying information that resort to the use of ontologies are being incorporsated in the Net, one of the main objectives of the so-called demantic Web. Another interesting novelty is the development of the social systems of classification and the notion of folksonomym, that comes from them.

Folksonomy, is a neologism that gives name to the categorización colaborativa por medio de etiquetas simples en un espacio de nombres llano, sin jerarquías ni relaciones de parentesco predeterminadas. It’s a practice that that is produced in the environments of the social software, whose best exponents are the shared places like del.icio.us (favourite links), Flickr (photos), Tagzania (places), o 43 Things (wishes).”

Taxonomy is the practice and science of classification of things. The word comes from the Greek ( taxis, ‘order’ + nomos, ‘law’ or ’science’). Taxonomies, are composed of taxonomic units known as taxa (singular taxon), or kinds of things that are arranged frequently in a hierarchical structure, a tree structure of classifications for a given set of objects. Almost anything may be classified according to some taxonomic scheme. The term taxonomy may also apply to other relationship schemes, such as network structures with other types of relationships.

A taxonomy might also be a simple organization of kinds of things into groups, or even an alphabetical list (the term vocabulary is more appropriate for such a list). In current usage within “Knowledge Management“, taxonomies are seen as less broad than ontologies as ontologies apply a larger variety of relation types.

Anthropologists have observed that taxonomies are generally embedded in local cultural and social systems and serve various social functions.

Various taxonomies

In phylogenetic taxonomy (or cladistic taxonomy), organisms can be classified by clades, which are based on evolutionary grouping by ancestral traits. By using clades as the criteria for separation, cladistic taxonomy, can categorize taxa into unranked groups.

In numerical taxonomy or taximetrics, the field of solving or best-fitting of numerical equations that characterize all measurable quantities of a set of objects is called cluster analysis.

Non-scientific taxonomy

Other taxonomies are sometimes called folk taxonomies to distinguish them from scientific taxonomies that claim to be disembedded from social relations and thus objective and universal.

The neologism folksonomy should not be confused with “folk taxonomy” (though it is obviously a contraction of the two words). Those who support scientific taxonomies have recently criticized folksonomies by dubbing them “fauxonomies” (French word “faux” means “false”).

FOLKSONOMIES

(also known as collaborative tagging, social classification, social indexing, social tagging, and other names) is the practice and method of collaboratively creating and managing tags to annotate and categorize content. Folksonomy is a distributed classification system with low entry costs.In contrast to traditional subject indexing, metadata is not only generated by experts but also by creators and consumers of the content. Usually, freely chosen keywords are used instead of a controlled vocabulary.

It is a portmanteau of the words folk and taxonomy that specifically refers to subject indexing systems created within Internet communities. According to Vander Wal, a folksonomy is “tagging that works”.

Folksonomy should be distinguished from folk taxonomy. Folk taxonomies are culturally supplied, intergenerationally transmitted, and relatively stable classification systems that people in a given culture use to make sense of the entire world around them^.

Folksonomies became popular on the Web with social software applications such as social bookmarking . Websites that support tagging and the principle of folksonomy are referred to in the context of Web 2.0 because participation is very easy and tagging data is used in new ways to find information. For example, tag clouds are frequently used to visualize the most used tags of a folksonomy. The term folksonomy is also used to denote only the set of tags that are created in social tagging.

Folksonomic tagging -typically, Internet-based- is intended to make a body of information increasingly easy to search, discover, and navigate over time. A well-developed folksonomy is ideally accessible as a shared vocabulary that is originated and familiar to its users. Two widely cited examples of websites using folksonomic tagging are Flickr and del.icio.us, although it has been suggested that Flickr is not a good example of folksonomy.

Part of the appeal of folksonomy is its inherent subversiveness: folksonomies can be seen as a rejection of the search engine status quo in favor of tools that are created by the community.

Folksonomy creation and searching tools are not part of the underlying World Wide Web protocols. Folksonomies arise in Web-based communities for creating and using tags in order to label and share user-generated content, such as photographs, Web sites, books, works in the scientific and scholarly literatures, and blog entries.

Folksonomy may hold the key to developing a Semantic Web, in which every Web page contains machine-readable metadata that describes its content. Such metadata would dramatically improve the precision in search engines. Few Web authors make use of the simple Dublin Core metadata standard, even though the use of Dublin Core meta-tags could increase their pages’ prominence in search engine retrieval lists.

Folksonomy is frequently criticized because of its lack of terminological control that it seems to be more likely to produce unreliable and inconsistent results, if tags are freely chosen instead of taken from a given vocabulary or inaccurate or irrelevant tags are used.

Idiosyncratic folksonomic classification, although considered beneficial by some, is viewed by others as a distinct limitation. For example, items tagged as “Web 2.0” represent a dizzying array of seemingly inconsistent and contradictory resources. The lack of a hierarchical or systematic structure for the tagging system makes the terms relevant to what they are describing, but often fails to show their relevancy or relationship to other objects of the same or similar type.

Folksonomy in the enterprise

Folksonomies are user-generated and therefore inexpensive to implement. It provides a useful low-cost alternative to more traditional, institutionally supported taxonomies or controlled vocabularies. It is useful in facilitating workplace democracy and the distribution of management tasks among people actually doing the work. As a distribution method, the folksonomy may facilitate workflow, but it does not guarantee that the information worker will tag.

Folksonomy and top-down taxonomies

Commentators and information architects have contrasted the hierarchical approach of top-down taxonomies with the folksonomy approach. The former approach is prevalent and represented by many practical examples.

One such example is Yahoo! — one of the earliest general directories for content on the Web. Yahoo! presented links under a fixed hierarchy.

Compromise with top-down taxonomies

It is possible that the differences between taxonomies and folksonomies have been overestimated. A possible solution to the shortcomings of folksonomies and controlled vocabulary is a collabulary. The result is a system that combines the benefits of folksonomies — low entry costs, a rich vocabulary that is broadly shared and comprehensible by the user base, and the capacity to respond quickly to language change — without the errors that inevitably arise in unsupervised folksonomies.

The ability to group tags, e.g. del.icio.us’s “bundles”, provides one way for taxonomists to work with an underlying folksonomy. Another possible solution is a taxonomy-directed-folksonomy, which relies on the user interfaces to suggest tags from a formal taxonomy, but allows many users to use their own tags.

ONTOLOGY

Is a study of conceptions of reality and the nature of being. Ontology (from the Greek “of being” and science, study, theory) is the study of being or existence and forms the basic subject matter of metaphysics. It seeks to describe or posit the basic categories and relationships of being or existence to define entities and types of entities within its framework. The first occurrence in English of “ontology” as recorded by the OED appears in Bailey’s dictionary of 1721, which defines ontology as ‘an Account of being in the Abstract’

Ontology concerns determining what categories of being are fundamental and asks whether, and in what sense, the items in those categories can be said to “be.”

The verb to be has many different meanings in different contexts and can therefore be rather ambiguous. Because “to be” has so many different meanings, there are, accordingly, many different ways of being.

All nouns refer to entities, collections, objects or events. In this latter view, mind, instead of referring to an entity, refers to a collection of mental events experienced by a person; society refers to a collection of persons with some shared interactions, and geometry refers to a collection of a specific kind of intellectual activity.

As a philosophical subject, ontology deals with the precise utilization of words as descriptors of entities or realities. Any ontology must give an account of which words refer to entities, which do not, why, and what categories result. The most basic problems in ontology are: finding a subject, a relationship, and an object to talk about.

Some basic questions

Ontology has one basic question: “What exists?”One common approach is to divide the extant entities into groups called “categories.” Ontology is applied to such fields as theology, information science and artificial intelligence.

Fundamental ontological concepts include:

• Universals
• Substance

Body and environment

Schools of subjectivism, objectivism and relativism existed at various times in the 20th century, and the postmodernists and body philosophers tried to reframe all these questions in terms of bodies taking some specific action in an environment. This relied to a great degree on insights derived from scientific research into animals taking instinctive action in natural and artificial settings—as studied by biology, ecology, and cognitive science.

The processes by which bodies related to environments became of great concern, and the idea of being itself became difficult to really define. Others, primarily philosophers, tried to dig into the word and its usage. Heidegger attempted to distinguish being and existence.

Ontological arguments are arguments from premises which are supposed to derive from some source other than observation of the world. This is, there are arguments from nothing but analytic, a priori and necessary premises to the conclusion that God exists. Issues of an ontological nature become of concern regarding discussions about possible descriptions of God. Anselm’s description of God is of “that of which nothing greater can be conceived.”

Ontology (computer science)

In both computer science and information science, an ontology is a data model that represents a set of concepts within a domain and the relationships between those concepts. It is used to reason about the objects within that domain.

Ontologies are used in artificial intelligence, the Semantic Web, software engineering, biomedical informatics and information architecture as a form of knowledge representation about the world or some part of it. Ontologies generally describe:

• Individuals: the basic or “ground level” objects, such as people, animals, things, molecules, and planets, as well as abstract individuals
• Classes: sets, collections, or types of objects. The classes of an ontology may be extensional or intensional in nature. A class is extensional if and only if it is characterized solely by its membership. If a class does not satisfy this condition, then it is intensional. A partition is a set of related classes and associated rules that allow objects to be placed into the appropriate class. If the partition rules ensure that every concrete object in the super-class is an instance of at least one of the partition classes, then the partition is called an exhaustive partition; if not, it is adisjoint partition.
• Attributes: properties, features, characteristics, or parameters that objects can have and share. The value of an attribute can be a complex data type. If you did not define attributes for the concepts you would have either a taxonomy (if hyponym relationships exist between concepts) or a controlled vocabulary. These are useful, but are not considered true ontologies.
• Relations: ways that objects can be related to one another. A tree-like structure (or, a partially ordered set) is the ‘child’ of a ‘parent class’. Another common type of relations is the meronymy relation, written as part-of, that represents how objects combine together to form composite objects.As well as the standard is-a and part-of relations, ontologies often include additional types of relation that further refine the semantics they model. These relations are often domain-specific and are used to answer particular types of question.
• Events: the changing of attributes or relations

Ontologies are commonly encoded using ontology languages.

Domain ontologies and upper ontologies

A domain ontology (or domain-specific ontology) models a specific domain, or part of the world. It represents the particular meanings of terms as they apply to that domain.

An upper ontology (or foundation ontology) is a model of the common objects that are generally applicable across a wide range of domain ontologies. It contains a core glossary in whose terms objects in a set of domains can be described. There are several standardized upper ontologies available for use, including Dublin Core, GFO, OpenCyc/ResearchCyc, SUMO, and DOLCEl. WordNet, while considered an upper ontology by some, is not an ontology: it is a unique combination of a taxonomy and a controlled vocabulary.

Since domain ontologies represent concepts in very specific and often eclectic ways, they are often incompatible.

At present, merging ontologies is a largely manual process and therefore time-consuming and expensive. Using a foundation ontology to provide a common definition of core terms can make this process manageable. There are studies on generalized techniques for merging ontologies, but this area of research is still largely theoretical.

Ontology languages

An ontology language is a formal language used to encode the ontology. There are a number of such languages for ontologies, both proprietary and standards-based:

• OWL is a language for making ontological statements, developed as a follow-on from RDF and RDFS, as well as earlier ontology language projects including OIL, DAML and DAML+OIL. OWL is intended to be used over the World Wide Web, and all its elements (classes, properties and individuals) are defined as RDF resources, and identified by URIs.
• KIF is a syntax for first-order logic that is based on S-expressions.
• The Cyc project has its own ontology language called CycL, based on first-order predicate calculus with some higher-order extensions.
• Rule Interchange Format (RIF) and F-Logic combine ontologies and rules.

In order to work with Ontology Languages, there is some useful technologies like Ontology Editor (to create ontologies using one of these languages), Ontology DBMS (to store and to query an ontology) and Ontology Warehouse (to integrate and to explore a set of related ontologies).

Relation to the philosophical term

The term ontology has its origin in philosophy, where it is the name of one fundamental branch of metaphysics, concerned with analyzing various types or modes of existence, often with special attention to the relations between particulars and universals, between intrinsic and extrinsic properties, and between essence and existence. According to Tom Gruber, the meaning of ontology in the context of computer science is “a description of the concepts and relationships that can exist for an agent or a community of agents.” An ontology is generally written, “as a set of definitions of formal vocabulary.”

What ontology has in common in both computer science and philosophy is the representation of entities, ideas, and events, along with their properties and relations, according to a system of categories.

Information taken from:

http://www.deli.deusto.es/wiki/index.php/Folk2onto

http://en.wikipedia.org/wiki/Taxonomy

http://en.wikipedia.org/wiki/Folksonomy

https://scholarsbank.uoregon.edu/dspace/bitstream/1794/3269/1/ccq_s ([PDF] Library of Congress controlled vocabularies and their application …