Preliminary experiments using subjective logic for the polyrepresentation of information needs

TY - CONF

T1 - Preliminary experiments using subjective logic for the polyrepresentation of information needs

AU - Lioma, Christina

AU - Larsen, Birger

AU - Ingwersen, Peter

N1 - Proceedings of the 4th Information Interaction in Context Symposium, Nijmegen, The Netherlands, August 21-24, 2012; edited by Jaap Kamps, Wessel Kraaij and Norbert Fuhr. ISBN: 978-1-4503-1282-0, p. 175-183.

PY - 2012/8/24

Y1 - 2012/8/24

N2 - According to the principle of polyrepresentation, retrieval accuracy may improve through the combination of multiple and diverse information object representations about e.g. the context of the user, the information sought, or the retrieval system [9, 10]. Recently, the principle of polyrep-resentation was mathematically expressed using subjective logic [12], where the potential suitability of each representation for improving retrieval performance was formalised through degrees of belief and uncertainty [15]. No experimental evidence or practical application has so far validated this model. We extend the work of Lioma et al. (2010) [15], by providing a practical application and analysis of the model. We show how to map the notions of belief and uncertainty to real-life evidence drawn from a retrieval dataset. We also show how to estimate two different types of polyrep-resentation assuming either (a) independence or (b) dependence between the information objects that are combined. We focus on the polyrepresentation of different types of context relating to user information needs (i.e. work task, user background knowledge, ideal answer) and show that the subjective logic model can predict their optimal combination prior and independently to the retrieval process.

AB - According to the principle of polyrepresentation, retrieval accuracy may improve through the combination of multiple and diverse information object representations about e.g. the context of the user, the information sought, or the retrieval system [9, 10]. Recently, the principle of polyrep-resentation was mathematically expressed using subjective logic [12], where the potential suitability of each representation for improving retrieval performance was formalised through degrees of belief and uncertainty [15]. No experimental evidence or practical application has so far validated this model. We extend the work of Lioma et al. (2010) [15], by providing a practical application and analysis of the model. We show how to map the notions of belief and uncertainty to real-life evidence drawn from a retrieval dataset. We also show how to estimate two different types of polyrep-resentation assuming either (a) independence or (b) dependence between the information objects that are combined. We focus on the polyrepresentation of different types of context relating to user information needs (i.e. work task, user background knowledge, ideal answer) and show that the subjective logic model can predict their optimal combination prior and independently to the retrieval process.

KW - Information Retrieval Teori

KW - Polyrepresentation

KW - Subjective logic

KW - Opinion fusion

M3 - Paper

ER -