Standards for Taxonomies

Since “taxonomies” are rather loosely defined, standards specifically for taxonomies do not exist, but there are standards that are relevant to taxonomies. A taxonomy is a kind of controlled vocabulary, and there are standards for controlled vocabularies. There are also standards specifically for thesauri, a kind of controlled vocabulary with which taxonomies typically share many features. 

Standards serve various purposes. Two leading purposes for standards are:

1. To ensure consistency and ease of use across different products or systems used by different users.
2. To ensure interoperability, the sharing or exchange of products/services/information.

Standards for Consistency

Standards aimed at ensuring consistency and ease of use would include buttons on devices, menus in user interfaces, pedals in cars. With such standards, users can expect the same experience from manufacturers or service providers and thus they are able to easily use products or systems from different manufacturers/providers/vendors. In the case of information systems, this kind of standard includes those for the design and style of book indexes and thesauri. These “standards” tend to be guidelines, recommendations, or accepted conventions, and not exactly strict standards, even if issued from a standards body. For thesauri, the “standard” is issued by the NationalInformation Standards Institute (NISO), but it is called a "guideline”: ANSI/NISOZ.39.19 Guidelines for the Construction of Monolingual Controlled Vocabularies. The corresponding ISO standard is ISO 25964 Part 1: Thesauri for Information Retrieval.

These guidelines cover style and form of terms, circumstances for creating the various kinds of relationships between terms, use of notes on terms, etc. They are all about how to create well-formed thesauri with consistent design features that are then easy and intuitive to use. For example, when a user sees that two terms are in a hierarchical relationship, the user understands that the narrower term is a kind of, instance of, or integral part of the broader term, and not merely an aspect of or some other related concept of the broader term. In fact, the end-user of a thesaurus does not even need to know and understand thesaurus principles to be able to make use of a thesaurus to find desired concepts and content.

Standards for Interoperability

The other kind of standards, those aimed at ensuring interoperability, would include standards for size and units of measure, data exchange, and communications protocols. Interoperability standards are important for those controlled vocabularies which are intended to be shared or reused. Thus, the content to which controlled vocabularies link can be accessed by third parties or made publicly accessible over the Web. Controlled vocabularies may be “reused”, if the original creator of a controlled vocabulary decides to license the vocabulary (without linked content) to other publishers to use on their own content, so that the second publisher does not have to reinvent a controlled vocabulary that already exists in same subject area.

Interoperability standards for controlled vocabularies include ZThes (a thesaurus schema for XML, which is has since gone out of style), World Wide Web Consortium (W3C) specifications for the Semantic Web including SKOS (Simple KnowledgeOrganization System) and the Web Ontology Language (OWL) for ontologies, and ISO 25964 Part 2: Interoperability with other vocabularies. Indeed, ISO 25964 covers consistency standards in its first part and interoperability standards in its second part. 

Metadata Schema

Since taxonomies or other controlled vocabularies may be used to provide terms that fill a certain metadata element/property/field within a larger set of metadata, the use of a standard metadata schema or model is yet another way in which interoperable standards involve taxonomies.  If structured content is to be shared or exchanged, the metadata fields need to be standardized with the same names, abbreviations, and purposes.

Examples of standard metadata schema include MARC for library materials, Dublin Core (DCMI) for generic online networked resources, IPTC (International Press Telecommunications Council) for photographs and other media, DDI (Data Documentation Initiative) for describing data from the social sciences, and PREMIS (Preservation Metadata: Implementation Strategies) for repositories of digital objects. Adopting such a metadata schema would be another way to enable sharing of content tagged with the metadata.

I was pleased to have the opportunity to learn more about information and publishing standards recently at the Society for Scholarly Publishing conference in attending pre-meeting seminar “All About Standards.”

"The Accidental Taxonomist," 2nd edition

Recently I was asked what I added to the newly published 2nd edition of my book, The Accidental Taxonomist. The additions and changes are summarized in the book's preface, so I have decided to post the entire preface here, which follows:


When I published the first edition of The Accidental Taxonomist, I knew that changes would be needed within a couple of years, mostly to reflect the changes in thesaurus management software vendors, as software is a volatile industry characterized by new companies, acquisitions, and some vendors going out of business. It was also expected that the website examples, given as screenshots in the book, would change. As it turned out, the changes were more widespread than anticipated. I ended up replacing all screenshots and adding some new ones (totaling 44), since even existing software vendors or websites had updated their user interfaces. More than half of the various website URLs found throughout the book also had to be updated.

In the area of software, what I did not anticipate was that software changes have gone beyond just who the vendors are and what features vendors have added. There have also been some notable trends, such as in the adoption of Semantic Web standards, the convergence of taxonomy and ontology support, and more web-based, cloud/software-as-a-service offerings. Thus, in addition to adding more software vendors (and removing a few), I have also added a short section summarizing all of these software trends.

Also with respect to software, the first edition made no mention of SharePoint, since SharePoint 2010, the first version to support taxonomies, came out the same year my book did. So this new edition includes some discussion of managing taxonomies in SharePoint. There is not the space here to go into all the details, so I explore specific topics, such as managing polyhierarchy in SharePoint, on my blog, also called The Accidental Taxonomist.

The standards have changed too. ANSI/NISO Z39.19 2005 Guidelines for the Construction, Format, and Management of Monolingual Controlled Vocabularies was reaffirmed in 2010, but more significantly ISO 2788 Guidelines for the Establishment and Development of Monolingual Thesauri and 5964 Guidelines for the Establishment and Development of Multilingual Thesauri have been replaced by ISO 25964 Thesauri and Interoperability with Other Vocabularies, Part 1 in 2011 and Part 2 in 2013. This is not merely a reorganization of parts. The changes also comprise new content in the area of interoperability, including the exchange of taxonomy data and mappings between vocabularies. Now ANSI/NISO Z39.19 is coming due for a new version, but it is a long process. With an eye to a wider international audience, in this edition I cite the ISO standard along with the ANSI/NISO standard whenever relevant.

In addition to the change in the ISO thesaurus standard, there is also a change involving the wider adoption of other kinds of standards, most significantly those associated with the Semantic Web. Although development had begun earlier, the World Wide Web Consortium (W3C) formally released the SKOS (Simple Knowledge Organization System) standard only in August 2009, when I was busy finalizing my manuscript for the first edition, before the extent of the eventual adoption of SKOS was known. Now it is quite common for taxonomy management software to follow the SKOS specifications of concept modeling and taxonomy output. So, more attention to SKOS is given in this edition.

Another trend, which was already underway at the time I wrote my first edition, but which I simply did not bother to consider in detail, is the convergence of metadata and taxonomy. So, I have added a short section on the topic. I needed the intervening years to actually work in areas where taxonomies and metadata meet, whether through consulting or in a department called Metadata Standards and Services, before I felt I could say something original on the subject.

As for the people who do taxonomy work, the accidental taxonomists, I conducted a new survey, which has shown that their backgrounds remain as diverse as they were when surveyed six years prior, but there are new stories and examples of how people got involved in this type of work and what they like about it. Meanwhile, the opportunities for taxonomists continue to grow. I executed the exact same search for jobs in fall of 2009 and again in fall of 2015, on the job board aggregator Indeed.com, and found the numbers of currently posted openings had significantly increased.

Although I considered myself quite experienced with various taxonomies at the time I wrote the first edition, I have continued to gain additional taxonomy work experience since, so here and there throughout the book I have added information based on further reflection. Thus, in the chapter on planning and designing a taxonomy, I have added some advice regarding designating facets for enterprise taxonomies, questions to ask during stakeholder interviews, how to conduct stakeholder workshops, and methods of testing taxonomies.

I had also started writing my blog the year after the first edition, but the blog post topics are not the same as the additions to this book. The Accidental Taxonomist blog allows me to explore tangents in more detail, and this book is already longer than needs to be!

Taxonomies are interesting in that some things about them are fundamental and do not change, such as the notion of a concept, its varied names, its hierarchical and nonhierarchical relationships with other concepts. But, as anything related to information technology, there are things about taxonomies that do change, such as how they are managed, implemented, and utilized. Thus, it is not only the varied subject matter that makes taxonomy work interesting, but also the various implementations and opportunities to take advantage of in new technologies, such as those related to the Semantic Web and Linked Open Data. Although this new edition addresses these topics, my ongoing blog will cover further considerations in such areas.

Vocabularies and Controlled Vocabularies

I have long considered a taxonomy as a particular, structured kind of controlled vocabulary. More recently, however, I have been hearing of “vocabularies” without the word “controlled” in front, although still for the purposes of information management and retrieval, which is cause to wonder: are controlled vocabularies and vocabularies the same thing or not?

Controlled Vocabularies

Definition
It’s the standards that drive the definitions and also the scope of meaning. “Controlled vocabularies” have been most authoritatively defined and scoped by ANSI/NISO Z39.19-2005 Guidelines for the construction, format, and management of monolingual controlled vocabularies. The Standard’s glossary defines it as: “A list of terms that have been enumerated explicitly.” Vocabulary control is an important part of the definition of controlled vocabularies, whereby synonyms are linked together, homographs are distinguished, and unambiguous concepts are defined or scoped.

Although not part of the standard’s name, ISO 25964 Thesauri and interoperability with other vocabularies (parts 1 and 2 published in 2011 and 2013) also defines controlled vocabularies in its glossary, where it states that a controlled vocabulary is a “prescribed list of terms, headings or codes, each representing a concept.” It is also noted: “Controlled vocabularies are designed for applications in which it is useful to identify each concept with one consistent label, for example when classifying documents, indexing them and/or searching them.”

Scope
As for what is included within the scope of controlled vocabularies, ANSI/NISO Z39.19-2005 states in its Scope section, on the first page that controlled vocabularies include:

• Lists of controlled terms
• Synonym rings
• Taxonomies
• Thesauri

In the ISO 25964, the scope of inclusion of controlled vocabularies is less clear. In the glossary definition for controlled vocabulary, it states: “Thesauri, subject heading schemes and name authority lists are examples of controlled vocabularies,” but a complete list of controlled vocabularies is not presented.

What is significant is that ISO 25964 does make a distinction between “controlled vocabulary” and just vocabulary. ISO 25964 describes more kinds of vocabularies, but then addresses the issue of vocabulary control in each.  Types of vocabularies that ISO 25964 discusses as having vocabulary control are:

• Thesauri
• Classification schemes
• Classification schemes for records management
• Taxonomies
• Subject heading schemes
• Name authority lists

According to ISO 25964 part 2, terminologies and ontologies usually have vocabulary control, but vocabulary control is not a requirement. So, it can be inferred that most but not all terminologies (discussed in my last blog post) or ontologies are controlled vocabularies. Name authority lists are “usually controlled vocabularies” according to ISO 25964 part 2 (section 23.1.1). Synonym rings do not have vocabulary control (section 24.2.3).

Structured Vocabularies

Definition
There is another designation less commonly used of “structured vocabulary.” It appears in the name of the British Standard, BS 8723 Structured vocabularies for information retrieval – Guide. BS 8723 was published in five parts over 2005 – 2008, revising and expanding on the earlier BS and ISO standards for monolingual and multilingual thesauri, and, in turn, became the basis for the current ISO 25964 pair of standards.

ISO 25964 also includes “structured vocabulary” in its glossary, defined as an “organized set of terms, headings or codes representing concepts and their inter-relationships, which can be used to support information retrieval,” and goes on to note: “A structured vocabulary can also be used for other purposes. In the context of information retrieval, the vocabulary needs to be accompanied by rules for how to apply the terms.”  Meanwhile, ANSI/NISO Z39.19-2005 does not mention “structured vocabularies.”

Scope
As for what is included within the scope of structured vocabularies, while that is not so clearly stated, it can be assumed, based on the title of BS 8723 Structured vocabularies for information retrieval – Guide, that the vocabularies included within the standard are all “structured vocabularies.” These are:

• Thesauri
• Classification schemes
• Business classification schemes for records management
• Taxonomies
• Subject heading schemes
• Ontologies
• Authority lists

ISO 25964 seems to use “vocabularies” and “structured vocabularies” somewhat interchangeably. While the standard’s title refers to “thesauri and … other vocabularies,” its foreword states “ISO 25964-2 will cover interoperability between different thesauri and with other types of structured vocabulary, such as classification schemes, name authority lists, ontologies, etc.”

If all the types of vocabularies in part 2 are indeed considered as “structured vocabularies” then the scope of structured vocabularies would cover:

• Thesauri
• Classification schemes
• Classification schemes for records management
• Taxonomies
• Subject heading schemes
• Ontologies
• Terminologies
• Name authority lists
• Synonym rings

The last two, however, might not be included as structured vocabularies. ISO 25964 part 2 says that name authority lists “may also be structured vocabularies” (23.1.1), implying that they are not always structured vocabularies, and it also explains that synonym rings are “not hierarchically structured.”

Vocabularies

The simple one-word designation of “vocabulary,” when used in the context of support for information retrieval, comprises all controlled and structured vocabularies, including those at the margin of the definitions or not always meeting their strict requirements of controlled or structured vocabularies, such as ontologies, terminologies, name authority lists, and synonym rings, along with other flat (unstructured) term lists.

Vocabularies, not necessarily controlled or structured, are also what are referred to in other frameworks or web contexts, such as SKOS (simple knowledge organization system) vocabularies, Semantic Web Vocabularies, and Linked Open Vocabularies.

What is interesting to note is what other topics are being discussed when the terms “controlled vocabulary” and “vocabulary” alone are used in ISO 25964 part 2 Interoperability with other vocabularies.  Controlled vocabularies are discussed in context of entry terms, pre-coordination, post-coordination, near synonyms, and indexing. Vocabularies in general are discussed in context of equivalence mapping, interoperability, resources and authorities, registries, multilingual types, and management software/systems.

Conclusions

Taxonomies, thesauri, subject heading schemes, and classification schemes are both controlled vocabularies and structured vocabularies. Most controlled vocabularies are structured vocabularies, and almost all structured vocabularies are controlled vocabularies.  But there are other vocabularies that do not meet the criteria of one definition or another, and to recognize and include them, especially as resources or for the mapping of terms, we refer to them as just vocabularies.

Taxonomies and Terminologies

The current specialties of taxonomy management and terminology management have different histories and serve different purposes, but they are in fact closely related, and taxonomies and terminologies can be linked to share knowledge. At the annual Taxonomy Boot Camp conference in Washington, DC, earlier this month I met a terminologist attendee (Beate Früh of Büro b3) from Germany, who explained to me that the fields are quite similar, and that’s why she was attending a taxonomy conference. Also at the conference I met a vendor of a new software company (Jochen Hummel, CEO of Coreon), whose product provides both taxonomy and terminology management.

As with the field of taxonomies and taxonomy management, there are varying definitions of terminologies and terminology management.  The original meanings of both taxonomy and terminology are as fields of study, with taxonomy being the study of naming and classifying and terminology being the study of terms and their use. More commonly though, we refer to taxonomies and terminologies as sets of terms or concepts for a particular subject area or purpose.

Definitions of terminology include “technical or special terms used in a business, art, science, or special subject” (www.merriam-webster.com), and a “set of designations belonging to one special language” (ISO 1087-1:2000, 3.5.1), with “each designation representing a concept” ISO 25964-2:2013. According to International Information Centre for Terminology (InfoTerm): "The systematic organization and definition of concepts is called terminology management – which also includes classification.” (T.E.R.M.I.N.O.L.O.G.Y. PDF)

Differences

There are several differences between taxonomies and terminologies. The most obvious difference is that taxonomies have hierarchical relationships between the terms/concepts so as to create an overall hierarchical structure, and terminologies generally do not. Other differences are that terminologies contain more detailed terms than are found in a taxonomy for a comparable subject area.  Furthermore, while taxonomies are limited to nouns and noun phrases (including verbal nouns), terminologies may contain some specific adjectives. Terminologies generally include definitions for every term, which is not so typical for taxonomies. Many terminologies are used  to support foreign language translation, so there are usually foreign language equivalents for every term, something found in only a small minority of taxonomies. In general, there is more data for a term in a terminology than in a taxonomy.

The most significant difference between taxonomies and terminologies is how they are used. Taxonomies serve information retrieval, through a combination of indexing/tagging use and browsing/navigation and/or search support. Rather than serve information retrieval, the main purposes of terminologies are to support standard use of terms, especially technical terms, with agreed-upon meaning for creating technical documentation and for foreign language translations. Translation has historically been the field of greatest use of terminologies. As such, many terminologists have a background in translation or linguistics. The co-authors of a leading book in the field of terminology, Handbook of Terminology Management, are both professors of translation.

Another difference is in regional use. Taxonomies are especially widely used in the United States and other English-speaking countries, while growing elsewhere too, whereas terminologies are more widely used in Europe and bilingual countries such as Canada. Member organizations of Infoterm, the independent international association focused on terminology, include numerous organizations in Europe, a few in each of Africa, Asia, Latin America, and Canada, but there are no organizations in the United States.

Finally, there are a greater number of standards for terminologies. There are a large number of currently published standards of ISO committee 37 for Terminology and Other Language and Content Resources, including five standards of the Principles and Methods subcommittee, 14 of the Terminographical and Lexicographical Working Methods subcommittee, and five standards of the Systems to Manage Terminology, Knowledge and Content subcommittee, including ISO 30042:2008 TermBase eXhange (TBX). For taxonomies, on the other hand, standards are fewer, or, if considering specifically taxonomies, there actually are no standards, as the most relevant standards are for thesauri (ISO 25964 or ANSI/NISO Z39.19), ontologies (OWL, based on RDF), or more broadly web-based knowledge organization systems(SKOS).

Similarities

Despite their differences, taxonomies and terminologies both are kinds of vocabularies or controlled vocabularies (depending on how “controlled vocabulary” is defined, the topic of my next blog post). The international standard ISO 25964 Thesauri and interoperability with other vocabularies, (part 1 in 2011 and part 2 in 2013) discusses the following “other” vocabularies (as listed in its table of contents): classification schemes, taxonomies, subject heading schemes, ontologies, terminologies, name authority lists, and synonym rings. Thus, terminologies are listed right along with taxonomies and ontologies. The United States standard ANSI/NISO Z39.19-2005 Guidelines for the Construction, Format and Management of Monolingual Controlled Vocabularies, however, does not include terminologies in its more limited scope: “Controlled vocabularies covered in by this Standard includes lists of controlled terms, synonyms rings, taxonomies, and thesauri.” (Section 2 Scope).

The most important similarity is that both taxonomies and terminologies refer to terms and unique concepts and not to mere words. As such, they often include and bring together synonyms or other variants to disambiguate concepts. While terminologies don’t characteristically have relationships between terms, they sometimes do.

Linkages

Due to these similarities, it is quite feasible to have connections, links, mappings, etc., between terms in a taxonomy and in a terminology.  Taxonomies and terminologies for internal content within the same organization will have a lot of overlap, so it makes sense to leverage the same knowledge bases and either reuse the same terms in taxonomies and terminologies or at least link/map the equivalencies, both to save effort and to ensure consistency of understanding across and organization. ISO 25964-2 Thesauri and interoperability with other vocabularies includes a section on guidelines for the interoperability between thesauri (and, by extension, taxonomies) and terminologies:

• Concepts may be mapped between a thesaurus and a terminology, and should follow the same methods and best practices as mapping between two thesauri (22.3.2)
• Terminologies are useful as sources for concept of terms when building or maintaining a thesaurus. They can also be referred to when writing scope notes. (22.3.3)
• A search thesaurus or synonym ring may be built using a combination of a thesaurus and a terminology. (22.3.4)

Hopefully, more organizations will be developing both taxonomies and terminologies where they are lacking and also build connections between the two.

Find out more about terminologies

• AILIA Language Industry Association (Canada): What is Terminology?
• Inforterm: Why Terminology
• International Network for Terminology (TermNet)
• Uwe Muegge. "Disciplining words: What you always wanted to know about terminology management" tcworld 2.3 (2007)

Enterprise Taxonomies vs. Traditional Taxonomies

A book that I have been reading (Structures for Organizing Knowledge: Exploring Taxonomies, Ontologies, and Other Schemas, by June Abbas, 2010) got me thinking about the comparison between corporate/enterprise taxonomies and other “traditional taxonomies”. I found it intriguing that Abbas presents corporate or “professional” taxonomies in the same chapter on personal information structures. Thus, a corporate taxonomy could more aptly be an extension of a personal knowledge organization system, rather than the customization of standard taxonomy or controlled vocabulary.  So, how are corporate taxonomies or enterprise taxonomies (corporate taxonomies that are specifically for use enterprise-wide) different from traditional (library science type) taxonomies or thesauri?

There are, in fact, multiple ways in which a corporate or enterprise taxonomy differs from the traditional taxonomies or controlled vocabularies used in libraries or in particular subject disciplines. Enterprise taxonomies in particular are:

1.      Relatively small in size

2.      Multifaceted

3.      Customized to an enterprise’s content

4.      Customized to an enterprise’s users

5.      Relatively informal

Size
An enterprise taxonomy tends to be relatively small in size with respect to the number of terms and depth of term levels. The size will depend largely on the complexity of an enterprise’s business (number of lines of business, for example), but the range of 1000-2000 terms in an taxonomy for an enterprise that has single line of business is typical. An organization may certainly supplement  this enterprise taxonomy with additional subject-specialized controlled vocabularies, particularly in the areas of research & development or product catalogs.

Faceted Nature
An enterprise taxonomy deals with a variety of content which is differentiated in more than one way, not just by subject matter. Content is typically organized and searched not merely for what it is “about” but also what its purpose is, what its source is, what type of content it is, and perhaps also for what market or customer type it is relevant. Thus, an enterprise taxonomy is usually organized into several facets to support faceted search or faceted browse (see my April 2012 post), which include: document type, file format, department or functional area, line of business or product/service category, geographical region, and market segment, in addition to a topical facet.

Content Customized
A corporate or enterprise taxonomy should be highly customized to an enterprise’s own unique content. While two companies in the same industry may have nearly identical products and services, their customer or member base could vary slightly, and they probably do not have identical organizational structures, procedures, and workflows. Thus, no two companies or organizations would have identical content. Organizations also differ in the quantity of different kinds of content they own and in the importance they assign to different types of content.

User Customized

Just as important as content-customization is user-customization. Corporate or enterprise taxonomies are designed to help an organization’s users (employees, and often also partners and customers) find content. Users include both those who upload/publish content to the intranet or content management system, often manually tagging it, and users who are looking for content. These are sometimes the same people and sometimes not. Also in consideration of the users, there may be a workflow or business rule aspect that is taken into consideration. Thus, the process of designing an enterprise or corporate taxonomy involves gathering input from users, via interviews and workshops. For this reason, the author Abbas has combined corporate taxonomies into the same chapter as personal taxonomies, because they are both highly user-centered.

Informal

Traditional discipline taxonomies (such as for living organisms), thesauri, book cataloging and classification systems follow industry standards for their design and construction, which can be quite rigid and formal. For general-purpose controlled vocabularies, there are the ANSI/NISO Z39.19  guidelines and ISO 25964-1 standard (see my March 2012 post), which allow more flexibility than library cataloging rules. The design of corporate or enterprise taxonomies should adhere to ANSI/NISO or ISO standards at a high level, but in practice, other practicalities and user needs and expectations should take precedence over a strict following of every detail of the standards.

Taxonomy Standards

 

I’ve written book reviews before, but recently a journal asked me to review a standard. It was ISO 25964-1 Thesauri and interoperability with other vocabularies, Part 1: Thesauri for information retrieval, which was published in 2011 by the International Organization for Standards. I was pleased to have the opportunity, because this way I obtained a copy which otherwise costs about US$260 (or whatever the current exchange rate equivalence of 238 Swiss Franc). Most taxonomists in the United States and beyond have some familiarity with the U.S. standard ANSI/NISO Z39.19 Guidelines for the Construction, Format, and Management of Monolingual Controlled Vocabularies, not merely because it is American, but because the PDF document is freely available from the National Information Standards Organization (NISO).

So, how do the two standards compare? They are very similar is style, format, level of detail, use of illustrative examples, suitability of a reference, etc. Although explanations are not identical, it is clear that there was some degree of cooperation, consultation, or at least communication among the author teams of each.  The differences between the two standards are in their scope, and that is obvious from their titles. The ISO standard covers both monolingual and multilingual thesauri in a single standard, whereas the ANSI/NISO standard takes up multilingual vocabularies in a separate document. Additionally, the ISO standard focuses on thesauri, leaving other types of vocabularies in the yet-to-be published part 2 document, whereas the ANSI/NISO standard covers all kinds of controlled vocabularies within a single standard publication.

There are implications with these differences. By combining guidance on multilingual in addition to monolingual thesauri in a single document, monolingual taxonomists who read the ISO standard will broaden their awareness of the uses and possibilities of multilingual taxonomies, and that’s a good thing. On the other hand, a standard that appears from its title to be just about “thesauri” is likely to be overlooked by taxonomists who work with other kinds of controlled vocabularies.

The importance of the standards should not be overlooked. Taxonomies are only useful if they are well constructed, and decades of experience, practice, and use have indicated the conventions by which the most usable and useful taxonomies should be built. In addition to prescribing what works, the standards also encourage consistency. Consistently designed taxonomies thus become familiar to users, who then know how to use them with minimal training. Users don’t have to be told what a narrower term is and where to find it, or what a related term is and what its purpose is.

Taxonomy or thesaurus standards are a particularly useful resource to taxonomists. Other information management standards (such as for cataloging, indexing, bibliographic citations, etc.) have been reproduced, republished, disseminated, etc. by numerous professional organizations, nongovernmental institutes, educational institutions, and in numerous books. There is no need for the average information professional to look up the original, primary source standard. Taxonomy construction, however, is not such an established discipline or activity. In the field of taxonomies, professional membership organizations are lacking (except for divisions or special interest groups of larger organizations), academic courses are merely nonstandard electives, and books are fewer. The nature of the free-for-all style of the web, which is the platform for most taxonomies today, also poses challenges to conformity in style. Therefore, there is in fact a greater need for the average taxonomist to consult the original, primary source of standards.

For most individual taxonomists, I would suggest that the ANSI/NISO standard is sufficient, and there is no need to also read the ISO standard. However, for an organization or enterprise engaged in taxonomy building and implementation, the additional ISO standard is probably a good investment. Finally, any taxonomist involved in teaching or consulting would also find the ISO standard a valuable additional resource.