biostudies-literatureTibely GHungarian National Science Fund (OTKA)e0165728https://www.ebi.ac.uk/biostudies/studies/S-EPMC5089747biostudies-literatureUnknown11(11)Hierarchical organization is prevalent in networks representing a wide range of systems in nature and society. An important example is given by the tag hierarchies extracted from large on-line data repositories such as scientific publication archives, file sharing portals, blogs, on-line news portals, etc. The tagging of the stored objects with informative keywords in such repositories has become very common, and in most cases the tags on a given item are free words chosen by the authors independently. Therefore, the relations among keywords appearing in an on-line data repository are unknown in general. However, in most cases the topics and concepts described by these keywords are forming a latent hierarchy, with the more general topics and categories at the top, and more specialized onesPloS oneComparing the Hierarchy of Keywords in On-Line News Portals.PMC5089747K105447Tibely GPollner PPalla GSousa-Rodrigues DfalseComparing the Hierarchy of Keywords in On-Line News Portals.Hierarchical organization is prevalent in networks representing a wide range of systems in nature and society. An important example is given by the tag hierarchies extracted from large on-line data repositories such as scientific publication archives, file sharing portals, blogs, on-line news portals, etc. The tagging of the stored objects with informative keywords in such repositories has become very common, and in most cases the tags on a given item are free words chosen by the authors independently. Therefore, the relations among keywords appearing in an on-line data repository are unknown in general. However, in most cases the topics and concepts described by these keywords are forming a latent hierarchy, with the more general topics and categories at the top, and more specialized ones2016-01-01T00:00:00Z20162025-05-18T12:27:27.348Z2025-05-18T12:27:27.348ZS-EPMC50897472780231910.1371/journal.pone.0165728