This book constitutes the thoroughly refereed proceedings of five workshops of the 13th International Conference on Web-Age Information Management, WAIM 2012, held in Harbin, China, in August 2012. The 34 revised full papers are organized in topical sections on the five following workshops: the First International Workshop on Graph Data Management and Mining (GDMM 2012), the Second International Wireless Sensor Networks Workshop (IWSN 2012), the First International Workshop on Massive Data Storage and Processing (MDSP 2012), the Third International Workshop on Unstructured Data Management...

This book analyzes unexpected preference query results for three problems: causality and responsibility problems, why-not and why questions, and why-few and why-many questions. Further, it refines preference queries and discusses how to modify the original preference query based on different objectives, in order to obtain satisfying results.