Evaluating the effort involved in relevance assessments for images

How assessors and end users judge the relevance of images has been studied in information science and information retrieval for a considerable time. The criteria by which assessors' judge relevance has been intensively studied, and there has been a large amount of work which has investigated how relevance judgments for test collections can be more cheaply generated, such as through crowd sourcing. Relatively little work has investigated the process individual assessors go through to judge the relevance of an image. In this paper, we focus on the process by which relevance is judged for images, and in particular, the degree of effort a user must expend to judge relevance for different topics. Results suggest that topic difficulty and how semantic/visual a topic is impact user performance and perceived effort.