Efficient group-by reverse skyline computation

The reverse skyline query is very useful in many decision making applications. Given a multi-dimensional dataset P and a query point q, the reverse skyline query returns all the points in P whose dynamic skyline contains q. Although the reverse skyline retrieval has been well-studied in the literature, there is, to the best of our knowledge, no prior work on one of the most intuitive and practical types of reverse skyline queries, namely, group-by reverse skyline (GRS) query, which retrieves the reverse skyline for each group in a specified dataset. We formalize the GRS query including monochromatic and bichromatic versions, and identify its properties, and then propose a set of efficient algorithms for computing the group-by reverse skyline. Extensive experimental evaluation using both real and synthetic datasets demonstrates the performance of our proposed algorithms in terms of effectiveness and efficiency under a variety of experimental settings.