PRISM: A Unified Framework of Parameterized Submodular Information Measures for Targeted Data Subset Selection and Summarization

With increasing data, techniques for finding smaller, yet effective subsets with specific characteristics become important. Motivated by this, we present PRISM, a rich class of Parameterized Submodular Information Measures, that can be used in applications where such targeted subsets are desired. We demonstrate the utility of PRISM in two such applications. First, we apply PRISM to improve a supervised model's performance at a given additional labeling cost by targeted subset selection (PRISM-TSS) where a subset of unlabeled points matching a target set are added to the training set. We show that PRISM-TSS generalizes and is connected to several existing approaches to targeted data subset selection. Second, we apply PRISM to a more nuanced targeted summarization (PRISM-TSUM) where data (e.g., image collections, text or videos) is summarized for quicker human consumption with additional user intent. PRISM-TSUM handles multiple flavors of targeted summarization such as query-focused, topic-irrelevant, privacy-preserving and update summarization in a unified way. We show that PRISM-TSUM also generalizes and unifies several existing past work on targeted summarization. Through extensive experiments on image classification and image-collection summarization we empirically verify the superiority of PRISM-TSS and PRISM-TSUM over the state-of-the-art.