The VLDB Journal — The International Journal on Very Large Data Bases

Reachability is a fundamental problem in graph analysis. In applications such as social networks and collaboration networks, edges are always associated with timestamps. Most existing works on reachability queries in temporal graphs assume that ...

Given a user-specified minimum degree threshold $\gamma$, a $\gamma$-quasi-clique is a subgraph where each vertex connects to at least $\gamma$ fraction of the other vertices. Quasi-clique is a natural definition for dense structures, so finding large and hence ...$$$$

More and more weakly structured, and irregular data sources are becoming available every day. The schema of these sources is useful for a number of tasks, such as query answering, exploration and summarization. However, although semantic web data ...

Clustering is a fundamental primitive in manifold applications. In order to achieve valuable results in exploratory clustering analyses, parameters of the clustering algorithm have to be set appropriately, which is a tremendous pitfall. We observe ...

Crowdsourcing has been a prevalent way to obtain answers for tasks that need human intelligence. In general, a crowdsourcing platform is responsible for allocating workers to each received task, with high-quality workers in priority. However, the ...$\frac{\mathrm{}}{\mathrm{}}$

Data exploration—the problem of extracting knowledge from database even if we do not know exactly what we are looking for —is important for data discovery and analysis. However, precisely specifying SQL queries is not always practical, such as “...

Influential nodes with rich connections in online social networks (OSNs) are of great values to initiate marketing campaigns. However, the potential influence spread that can be generated by these influential nodes is hidden behind the structures ...

In many fields, e.g., data mining and machine learning, distance-based outlier detection (DOD) is widely employed to remove noises and find abnormal phenomena, because DOD is unsupervised, can be employed in any metric spaces, and does not have ...