1. A method, comprising: identifying clusters of images in a collection of images, wherein each cluster mostly contains images of a face of a person characterizing the cluster; accepting a user interaction to label each cluster; iteratively formulating proposed clusters from remaining images in the collection to solicit subsequent user interactions for labeling images in each proposed cluster, and wherein each iteration of the formulating proposes a cluster such that the subsequent user interactions maximize an information efficiency for subsequently labeling the remaining images in the collection while using a minimum number of user interactions.