User-generated collection-level metadata in an online photo-sharing system

Photoset and group descriptions in Flickr, a large-scale online photo-sharing system, offer insight into the collection description and collection building practices of Flickr users. Photosets, assembled by individual users, appear to evolve from the bottom-up, derived from the components of an individual user's context, and are based on selected attributes which a particular user's photos share. Group collections, on the other hand, seem to be organized more around general concepts or discussions relevant to the group members' work and are constructed top-down by matching specific photo attributes with the purpose of the group. This article identifies 10 categories of characteristics that Flickr users might use for forming these digital photo collections and discusses differences observed between photoset and group collection describing and building behavior. The categories are then compared with the classes and elements of some current metadata schemas and an ontology, as well as with the results of earlier research on individual behavior in describing individual items. The study shows that systematic investigation of user-generated collection-level metadata in Flickr and other similar open-tagging sites is needed to help inform better design of collection metadata schemas and other information organization tools.