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arXiv · 1902.10963

Learning partially ranked data based on graph regularization

Kento Nakamura·Keisuke Yano·Fumiyasu Komaki
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Abstract

Ranked data appear in many different applications, including voting and consumer surveys. There often exhibits a situation in which data are partially ranked. Partially ranked data is thought of as missing data. This paper addresses parameter estimation for partially ranked data under a (possibly) non-ignorable missing mechanism. We propose estimators for both complete rankings and missing mechanisms together with a simple estimation procedure. Our estimation procedure leverages a graph regularization in conjunction with the Expectation-Maximization algorithm. Our estimation procedure is theoretically guaranteed to have the convergence properties. We reduce a modeling bias by allowing a non-ignorable missing mechanism. In addition, we avoid the inherent complexity within a non-ignorable missing mechanism by introducing a graph regularization. The experimental results demonstrate that the proposed estimators work well under non-ignorable missing mechanisms.

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Kento Nakamura, Keisuke Yano, Fumiyasu Komaki. 2019-02-28. Learning partially ranked data based on graph regularization. https://arxiv.org/abs/1902.10963

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