| Vol-630 urn:nbn:de:0074-630-0 Copyright © 2010 for the individual papers by the papers' authors. Copying permitted only for private and academic purposes. This volume is published and copyrighted by its editors.

# LSDS-IR 2010
Large-Scale Distributed Systems for Information Retrieval 2010

### Proceedings of the 8th Workshop on Large-Scale Distributed Systems for Information Retrieval

### Co-located with ACM SIGIR. Geneva, Switzerland, July 23, 2010.

Edited by

### Roi Blanco *
B. Barla Cambazoglu *
Claudio Lucchese **

* Yahoo! Research, Barcelona, Spain
** ISTI-CNR, Pisa, Italy

## Table of Contents

### Invited Talks

1. Twitter 5
   Abdur Chowdhury (Twitter)
2. Towards a Distributed Search Engine 6
   Ricardo Baeza-Yates (Yahoo!)

### Regular papers

3. Query-Based Sampling using Snippets 7-12
   Almer S. Tigelaar, Djoerd Hiemstra (University of Twente)
4. RankReduce - Processing K-Nearest Neighbor Queries on Top of MapReduce 13-18
   Aleksandar Stupar, Sebastian Michel, Ralf Schenkel (Saarland University)
5. Topic-based Index Partitions for Efficient and Effective Selective Search 19-24
   Anagha Kulkarni, Jamie Callan (Carnegie Mellon University)
6. Scaling Out All Pairs Similarity Search with MapReduce 25-30
   Gianmarco De Francisci Morales, Claudio Lucchese, Ranieri Baraglia (IMT Lucca, Italy; ISTI-CNR, Italy)
7. Efficient Dynamic Pruning with Proximity Support (Best Paper) 31-35
   Nicola Tonellotto, Craig Macdonald, Iadh Ounis (ISTI-CNR, Italy; University of Glasgow)
8. Performance Evaluation of Large-scale Information Retrieval Systems Scaling Down (Position Paper) 36-39
   Fidel Cacheda, Victor Carneiro, Diego Fernandez, Vreixo Formoso (University of A Coruña)

The whole proceedings can also be downloaded as a single file (pdf).

14-Sep-2010: submitted by Claudio Lucchese
15-Sep-2010: published on CEUR-WS.org
22-Sep-2010: correct affiliations of papers 6 and 7