The outbreak of COVID-19 on the Diamond Princess cruise ship has attracted much attention. Motivated by the PCR testing data on the Diamond Princess, we propose a novel cure mixture nonparametric model to investigate the detection pattern. It combines a logistic regression for the probability of susceptible subjects with a nonparametric distribution for the detection of infected individuals. Maximum likelihood estimators are proposed. The resulting estimators are shown to be consistent and asymptotically normal. Simulation studies demonstrate that the proposed approach is appropriate for practical use. Finally, we apply the proposed method to PCR testing data on the Diamond Princess to show its practical utility.

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To cite this article: Huijuan Ma, Jing Qin, Fang Chen & Yong Zhou (2023) A novel nonparametric mixture model for the detection pattern of COVID-19 on Diamond Princess cruise, Statistical Theory and Related Fields, 7:1, 85-96, DOI: 10.1080/24754269.2022.2156743 To link to this article: https://doi.org/10.1080/24754269.2022.2156743