Has portfolio theory got any principles?

Recently, Portfolio Theory (PT) has been proposed for Information Retrieval. However, under non-trivial conditions PT violates the original Probability Ranking Principle (PRP). In this poster, we shall explore whether PT upholds a different ranking principle based on Quantum Theory, i.e. the Quantum Probability Ranking Principle (QPRP), and examine the relationship between this new model and the new ranking principle. We make a significant contribution to the theoretical development of PT and show that under certain circumstances PT upholds the QPRP, and thus guarantees an optimal ranking according to the QPRP. A practical implication of this finding is that the parameters of PT can be automatically estimated via the QPRP, instead of resorting to extensive parameter tuning. Categories and Subject Descriptors: H.3.3 Information Storage and Retrieval - Retrieval Models General Terms: Theory, Experimentation

• Type: Conference
• Year: 2010
• Where: SIGIR
• Authors: Guido Zuccon, Leif Azzopardi, Keith van Rijsbergen
• Keywords: Information Technology, Portfolio Theory, Probability Ranking Principle, Ranking Principle, SIGIR 2010