Published in The VLDB Journal
With the rapid development of information technologies, various big graphs are prevalent in many real applications (e.g., social media and knowledge bases). An important component of these graphs is the network community. Essentially, a community is a group of vertices which are densely connected internally. Community retrieval can be used in many ...
Published in The VLDB Journal
User data is becoming increasingly available in multiple domains ranging from the social Web to retail store receipts. User data is described by user demographics (e.g., age, gender, occupation) and user actions (e.g., rating a movie, publishing a paper, following a medical treatment). The analysis of user data is appealing to scientists who work o...
Published in The VLDB Journal
Many popular applications, such as collaborative document editing, sentence translation, or citizen science, resort to collaborative crowdsourcing, a special form of human-based computing, where, crowd workers with appropriate skills and expertise are required to form groups to solve complex tasks. While there has been extensive research on workers...
Published in The VLDB Journal
Crowdsourcing has been established as an essential means to scale human computation in diverse Web applications, reaching from data integration to information retrieval. Yet, crowd workers have wide-ranging levels of expertise. Large worker populations are heterogeneous and comprise a significant amount of faulty workers. As a consequence, quality ...
Published in The VLDB Journal
Set similarity join, which finds all the similar set pairs from two collections of sets, is a fundamental problem with a wide range of applications. Existing works study both exact set similarity join and approximate similarity join problems. In this paper, we focus on the exact set similarity join problem. The existing solutions for exact set simi...
Published in The VLDB Journal
The Resource Description Framework (RDF) is a W3C standard for representing graph-structured data, and SPARQL is the standard query language for RDF. Recent advances in information extraction, linked data management and the Semantic Web have led to a rapid increase in both the volume and the variety of RDF data that are publicly available. As busin...
Published in The VLDB Journal
Query optimizers depend heavily on statistics representing column distributions to create good query plans. In many cases, though, statistics are outdated or nonexistent, and the process of refreshing statistics is very expensive, especially for ad hoc workloads on ever bigger data. This results in suboptimal plans that severely hurt performance. T...
Published in The VLDB Journal
Relational learning algorithms learn the definition of a new relation in terms of existing relations in the database. The same database may be represented under different schemas for various reasons, such as efficiency, data quality, and usability. Unfortunately, the output of current relational learning algorithms tends to vary quite substantially...
Published in The VLDB Journal
Social networks offer various services such as recommendations of social events, or delivery of targeted advertising material to certain users. In this work, we focus on a specific type of services modeled as constrained graph partitioning (CGP). CGP assigns users of a social network to a set of classes with bounded capacities so that the similarit...
Published in The VLDB Journal
Social media recommendation has attracted great attention due to its wide applications in online advertisement and entertainment, etc. Since contexts highly affect social user preferences, great effort has been put into context-aware recommendation in recent years. However, existing techniques cannot capture the optimal context information that is ...
