Archive for the ‘Folksonomy’ Category

Taxonomies Make the Law. Will Folksonomies Change It?

Wednesday, May 1st, 2013

Taxonomies Make the Law. Will Folksonomies Change It? by Serena Manzoli.

From the post:

Take a look at your bundle of tags on Delicious. Would you ever believe you’re going to change the law with a handful of them?

You’re going to change the way you research the law. The way you apply it. The way you teach it and, in doing so, shape the minds of future lawyers.

Do you think I’m going too far? Maybe.

But don’t overlook the way taxonomies have changed the law and shaped lawyers’ minds so far. Taxonomies? Yeah, taxonomies.

We, the lawyers, have used extensively taxonomies through the years; Civil lawyers in particular have shown to be particularly prone to them. We’ve used taxonomies for three reasons: to help legal research, to help memorization and teaching, and to apply the law.

Serena omits one reason lawyers use taxonomies: Knowledge of a taxonomy, particularly a complex one, confers power.

Legal taxonomies also exclude the vast majority of the population from meaningful engagement in public debates, much less decision making.

To be fair, some areas of the law are very complex, securities and tax law come to mind. Even without the taxonomy barrier, mastery is a difficult thing.

Serena’s example of navigable waters reminded me of one of my law professors who in separate cases, lost both sides of the question of navigability of a particular water way. 😉

I am hopeful that Serena is correct about the coming impact of folksonomies on the law.

But I am also mindful that legal “reform” rarely emerges from the gauntlet of privilege unscathed.

I first saw this at: Manzoli on Legal Taxonomies and Legal Folksonomies.

Measuring Similarity in Large-scale Folksonomies [Users vs. Authorities]

Tuesday, September 11th, 2012

Measuring Similarity in Large-scale Folksonomies by Giovanni Quattrone, Emilio Ferrara, Pasquale De Meo, and Licia Capra.


Social (or folksonomic) tagging has become a very popular way to describe content within Web 2.0 websites. Unlike taxonomies, which overimpose a hierarchical categorisation of content, folksonomies enable end-users to freely create and choose the categories (in this case, tags) that best describe some content. However, as tags are informally defined, continually changing, and ungoverned, social tagging has often been criticised for lowering, rather than increasing, the efficiency of searching, due to the number of synonyms, homonyms, polysemy, as well as the heterogeneity of users and the noise they introduce. To address this issue, a variety of approaches have been proposed that recommend users what tags to use, both when labelling and when looking for resources.

As we illustrate in this paper, real world folksonomies are characterized by power law distributions of tags, over which commonly used similarity metrics, including the Jaccard coefficient and the cosine similarity, fail to compute. We thus propose a novel metric, specifically developed to capture similarity in large-scale folksonomies, that is based on a mutual reinforcement principle: that is, two tags are deemed similar if they have been associated to similar resources, and vice-versa two resources are deemed similar if they have been labelled by similar tags. We offer an efficient realisation of this similarity metric, and assess its quality experimentally, by comparing it against cosine similarity, on three large-scale datasets, namely Bibsonomy, MovieLens and CiteULike.

Studying language (tags) as used tells you about users.

Studying language as proscribed by an authority, tells you about that authority.

Which one is of interest to you?

Survey on Social Tagging Techniques

Monday, December 6th, 2010

Survey on Social Tagging Techniques Authors: Manish Gupta, Rui Li, Zhijun Yin, Jiawei Han Keywords: Social tagging, bookmarking, tagging, social indexing, social classification, collaborative tagging, folksonomy, folk classification, ethnoclassification, distributed classification, folk taxonomy


Social tagging on online portals has become a trend now. It has emerged as one of the best ways of associating metadata with web objects. With the increase in the kinds of web objects becoming available, collaborative tagging of such objects is also developing along new dimensions. This popularity has led to a vast literature on social tagging. In this survey paper, we would like to summarize different techniques employed to study various aspects of tagging. Broadly, we would discuss about properties of tag streams, tagging models, tag semantics, generating recommendations using tags, visualizations of tags, applications of tags and problems associated with tagging usage. We would discuss topics like why people tag, what influences the choice of tags, how to model the tagging process, kinds of tags, different power laws observed in tagging domain, how tags are created, how to choose the right tags for recommendation, etc. We conclude with thoughts on future work in the area.

I recommend this survey in part due to its depth but also for not lacking a viewpoint:

…But fixed static taxonomies are rigid, conservative, and centralized. [cite omitted]…Hierarchical classifications are influenced by the cataloguer’s view of the world and, as a consequence, are affected by subjectivity and cultural bias. Rigid hierarchical classification systems cannot easily keep up with an increasing and evolving corpus of items…By their very nature, hierarchies tend to establish only one consistent, authoritative structured vision. This implies a loss of precision, erases differences of expression, and does not take into account the variety of user needs and views.

I am not innocent of having made similar arguments in other contexts. It makes good press among the young and dissatisfied, it doesn’t bear up to close scrutiny.

For example, the claim is made that “hierarchical classifications” are “affected by subjectivity and cultural bias.” The implied claim is that social tagging is not. Yes? I would argue that all classification, hierarchical and otherwise is affected by “subjectivity and cultural bias.”


  1. Choose one of the other claims about hierarchical classifications. Is is also true of social tagging? Why/Why not? (3-5 pages, no citations)
  2. Choose a social tagging practice. What are its strengths/weaknesses? (3-5 pages, no citations)
  3. How would you use topic maps with the social tagging practice in #2? (3-5 pages, no citations)

to_be_classified: A Facet Analysis of a Folksonomy

Monday, December 6th, 2010

to_be_classified: A Facet Analysis of a Folksonomy Author Elise Conradi Keywords Facet analysis, Faceted classification, VDP::Samfunnsvitenskap: 200::Biblioteks- og informasjonsvitenskap: 320::Kunnskapsgjenfinning og organisering: 323


This research examines Ranganathan’s postulational approach to facet analysis with the intention of manually inducing a faceted classification ontology from a folksonomy. Folksonomies are viewed as a source to a wealth of data representing users’ perspectives. An in-depth study of faceted classification theory is used to form a methodology based on the postulational approach. The dataset used to test the methodology consists of over 107,000 instances of 1,275 unique tags representing 76 popular non-fiction history books collected from the LibraryThing folksonomy. Preliminary results of the facet analysis indicate the manual inducement of two faceted classification ontologies in the dataset; one representing the universe of books and one representing the universe of subjects within the universe of books. The ontology representing the universe of books is considered to be complete, whereas the ontology representing the universe of subjects is incomplete. These differences are discussed in light of theoretical differences between special and universal faceted classifications. The induced ontologies are then discussed in terms of their substantiation or violation of Ranganathan’s Canons of Classification.

Highly recommended. Expect back references to this entry in the coming months.


  1. Is Ranganathan’s “idea plane” for work in classification different from Husserl’s “bracketing?” If so, how? (3-5 pages, citations)
  2. How would you distinguish the “idea plane” from the “verbal plane?” (3-5 pages, no citations)
  3. How would you compare the “idea planes” as seen by two different classifiers? (3-5 pages, no citations)