1. A method for efficiently identifying images, videos, audio files or documents relevant to a user using attribute binary trees for guiding relevance feedback, the method comprising: constructing a binary search tree for each relative attribute of interest in a pool of database images, videos, audio files or documents; setting a current pivot exemplar for each binary tree as corresponding to a database image, video, audio file or document with a median relative attribute value among all remaining database items in a subtree; predicting an information gain that would result from asking a user how a user's target image, video, audio file or document compares to each pivot exemplar of a plurality of pivot exemplars, wherein said comparison is made in terms of an attribute associated with that pivot's binary tree; providing a pivot exemplar deemed most informative from among said plurality of pivot exemplars to a user to provide a comparison between said attribute in said user's target image, video, audio file or document and in said current pivot exemplar; and receiving, by a processor, comparative attribute feedback from said user regarding whether a degree of said attribute in said user's target image, video, audio file or document is more, less or equal with said attribute displayed in said provided pivot exemplar.