Semiparametric inference of the Youden index and the optimal cut‐off point under density ratio models

@article{Yuan2021SemiparametricIO,
  title={Semiparametric inference of the Youden index and the optimal cut‐off point under density ratio models},
  author={Meng Yuan and Pengfei Li and Changbao Wu},
  journal={Canadian Journal of Statistics},
  year={2021},
  volume={49}
}
The Youden index is a popular summary statistic for receiver operating characteristic curves. It gives the optimal cut‐off point of a biomarker to distinguish the diseased and healthy individuals. In this article, we model the distributions of a biomarker for individuals in the healthy and diseased groups via a semiparametric density ratio model. Based on this model, we propose using the maximum empirical likelihood method to estimate the Youden index and the optimal cut‐off point. We further… 
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