Need to Categorize: A Comparative Look at the Categories of Universal Decimal Classification System and Wikipedia

Abstract

This study analyzes the differences between the category structure of the Universal Decimal Classification (UDC) system (which is one of the widely used library classification systems in Europe) and Wikipedia. In particular, we compare the emerging structure of category-links to the structure of classes in the UDC. With this comparison we would like to scrutinize the question of how do knowledge maps of the same domain differ when they are created socially (i.e. Wikipedia) as opposed to when they are created formally (UDC) using classification theory. As a case study, we focus on the category of "Arts".In modern times, the fast expansion of human knowledge makes categories a necessity in managing and accessing produced knowledge. The science of 'knowledge orders', i.e. taxonomies, classifications, etc., is born out of this need. However today, with all the tools the information society has to offer, taxonomies have a powerful opponent: folksonomies.Folksonomies are an outcome of the phenomenon of collective writing, and collaborative tagging. Wikipedia is one favorite object for studying such behavior. For a long time, Wikipedia relied only on search engines for information retrieval, and its users browsed the content by following simple links (called

Science through Wikipedia: A novel representation of open knowledge through co-citation networks

“…Networks have also been used for knowledge representation in order to visualize differences between the Universal Decimal Classification category structure and that generated by Wikipedia itself [14], to generate automated taxonomies and visualizations of scientific fields [15], and to show connections between articles [16]; furthermore, studies based on the complex networks approach have also been reported [17].…”

Mapping the backbone of the Humanities through the eyes of Wikipedia

“…For example, through the analysis of reference and citation patterns in a specific scientific area ( Serrano-López, Ingwersen & Sanz-Casado , 2017), as a platform for the promotion of open access scientific literature (Teplitskiy, Lu & Duede, 2016), or by exploring its limitations as a source in the evaluation of scientific activity (Kousha & Thelwall, 2016). Knowledge representation has also been formulated through reference maps connecting articles (Silva et al, 2011), or by analyzing differences between the Universal Decimal Classification (UDC) category structure and that generated by Wikipedia itself (Salah et al, 2012).…”

Cleansing Wikipedia Categories using Centrality

“…Indeed, the category graph is far from perfect: since the very notion of "subcategory" is fuzzy and no universal policy is strictly enforced, the resulting hierarchy is not a forest, and not even a directed acyclic graph, as [11] pointed out. The category graph has been described instead as a thesaurus that combines collaborative tagging and hierarchical subject indexing by [22] and as an overlay between different trees by [15].…”

“…Diverse techniques have been tried to do that. Common examples include considering only a tree based in a root category (from a global root [9] or a local one [24,15]); others have arbitrarly removed cycles [7]. However, to the best of our knowledge, a work focusing on this denoising operation, comparing different techniques, was still missing.…”