With the broad adoption of mobile devices, notably smartphones, keyword-based search for
content has seen increasing use by mobile users, who are often interested in content related …

Matching similar pairs of trajectories, called trajectory similarity join, is a fundamental
functionality in spatial data management. We consider the problem of semantic trajectory …

Large volumes of geo-tagged text objects are available on the web. Spatial keyword top-k
queries retrieve k such objects with the best score according to a ranking function that takes …

This work considers why-not questions in the context of top-k queries and score-based
ranking functions. Following the popular linear scalarization approach for multi-objective …

Over the past decade, we have moved from a predominantly desktop based web to a
predominantly mobile web, where users most often access the web from mobile devices …

Identifying prospective customers is an important aspect of marketing research. In this paper,
we provide support for a new type of query, the Reverse Top-k Geo-Social Keyword …

Why-not and why questions can be posed by database users to seek clarifications on
unexpected query results. Specifically, why-not questions aim to explain why certain …

A top-k geo-social keyword (TkGSK) query retrieves the objects by considering spatial,
social, and textual constraints. After a user issues an initial TkGSK query and gets back its …

With advances in geo-positioning technologies and mobile internet, location-based services
have attracted much attention, and spatial keyword queries are catching on fast. However …

With the continued proliferation of location-based services, a growing number of web-
accessible data objects are geo-tagged and have text descriptions. An important query over …