This volume contains revised and extended versions of papers presented
at the 4th edition of the international workshop on Distributed and
Agent-based Retrieval Tools (DART'10) held in June 2010, in conjunction
with the Symposium on Human Language Technology for the Information
Society, in Geneva, Switzerland. Practitioners and researchers working
on pervasive and intelligent access to web services and distributed
information retrieval met to share their results and insights in
intriguing and challenging topics such as: (i) social media and
collaboration, (ii) new challenges in search technology, (iii) sentiment
analysis and opinion mining, (iv) distributed information retrieval, (v)
pervasive intelligence. Every chapter, before discussing in depth the
specific topic, presents a comprehensive review of related work and
state of the art, in the hope of this volume to be of use in the years
to come, to both researchers and students.