Tag, cloud and ontology based retrieval of images

In this paper, we describe the results of an experiment designed to compare different user interfaces for retrieving tagged images from a database comprised of images of Jewish cultural heritage. The participants were given ten scenarios, for which they were asked to retrieve all the relevant images in the database. Each participant was randomly assigned to one of four retrieval interfaces: tag search in a search box; faceted tag search in a search box, selecting terms from the tag cloud of all the tags in the database and selecting concepts from an ontology created from the tags assigned to the images. Each interface was tested by 21 users. The results show that the highest recall on average was achieved by users of the ontology interface, for seven out of the ten tasks, however users were more satisfied with the textbox based search than the cloud or the ontology. Differences between the precision values were small (less than 10%), but none of the interfaces clearly outdid the others. In terms of recall, on average there was a 27% difference between the group achieving the highest and lowest recall.