Title
An in-depth study on diversity evaluation: The importance of intrinsic diversity.
Abstract
Diversified document ranking has been recognized as an effective strategy to tackle ambiguous and/or underspecified queries. In this paper, we conduct an in-depth study on diversity evaluation that provides insights for assessing the performance of a diversified retrieval system. By casting the widely used diversity metrics (e.g., ERR-IA, α-nDCG and D#-nDCG) into a unified framework based on marginal utility, we analyze how these metrics capture extrinsic diversity and intrinsic diversity. Our analyses show that the prior metrics (ERR-IA, α-nDCG and D#-nDCG) are not able to precisely measure intrinsic diversity if we merely feed a set of subtopics into them in a traditional manner (i.e., without fine-grained relevance knowledge per subtopic). As the redundancy of relevant documents with respect to each specific information need (i.e., subtopic) can not be then detected and solved, the overall diversity evaluation may not be reliable. Furthermore, a series of experiments are conducted on a gold standard collection (English and Chinese) and a set of submitted runs, where the intent-square metrics that extend the diversity metrics through incorporating hierarchical subtopics are used as references. The experimental results show that the intent-square metrics disagree with the diversity metrics (ERR-IA and α-nDCG) being used in a traditional way on top-ranked runs, and that the average precision correlation scores between intent-square metrics and the prior diversity metrics (ERR-IA and α-nDCG) are fairly low. These results justify our analyses, and uncover the previously-unknown importance of intrinsic diversity to the overall diversity evaluation.
Year
DOI
Venue
2017
10.1016/j.ipm.2017.03.001
Information Processing & Management
Keywords
Field
DocType
Extrinsic diversity,Intrinsic diversity,Marginal utility
Data mining,Information retrieval,Ranking,Computer science,Correlation,Specific-information,Redundancy (engineering),Marginal utility,Instrumental and intrinsic value
Journal
Volume
Issue
ISSN
53
4
0306-4573
Citations 
PageRank 
References 
2
0.42
30
Authors
5
Name
Order
Citations
PageRank
Yu Haitao1178.10
Adam Jatowt2903106.73
Roi Blanco387257.42
Hideo Joho488170.47
Joemon M. Jose52782198.37