On Theoretically Valid Score Distributions in Information Retrieval

摘要

In this paper, we aim to investigate the practical usefulness of the Recall-Fallout Convexity Hypothesis (RFCH) for a number of document score distribution (SD) models. We compare SD models that do not automatically adhere to the RFCH to modified versions of the same SD models that do adhere to the RFCH. We compare these models using the inference of average precision as a measure of utility. For the three models studied in this paper, we conclude that adhering to the RFCH is practically useful for the two-normal model, makes no difference for the two-gamma model, and degrades the performance of the two-lognormal model.