Thesis Defense by WANG Yiyi | Finding top-m leading records in temporal data

Traditional top-k queries filter the records standing out at a certain point-in-time. Considering how long they retain the supremacy, a durable top-k query finds the set of objects that are consistently in the top-k results throughout a given time interval. In this thesis, I propose a problem of finding the top-m leading records, that rank among the top k for the longest duration within the query interval. Such query assesses the records by not only the ranking of their scores, but also how long they stay ahead. I present a solution and perform a case study with NBA dataset to demonstrate the effectiveness of it. Experiments using synthetic and real dataset are also conducted to examine its efficiency.

Wang Yiyi received the bachelor degree in Information Systems from Singapore Management University. She is currently working toward the MSc degree in Information Systems with the School of Computing and Information Systems, Singapore Management University, Singapore. She is interested in spatial databases and preference-based queries.