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arXiv · 2003.10484

Large-P Variable Selection in Two-Stage Models

Haim Bar·Kangyan Liu
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Abstract

Model selection in the large-P small-N scenario is discussed in the framework of two-stage models. Two specific models are considered, namely, two-stage least squares (TSLS) involving instrumental variables (IVs), and mediation models. In both cases, the number of putative variables (e.g. instruments or mediators) is large, but only a small subset should be included in the two-stage model. We use two variable selection methods which are designed for high-dimensional settings, and compare their performance in terms of their ability to find the true IVs or mediators. Our approach is demonstrated via simulations and case studies.

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Haim Bar, Kangyan Liu. 2020-03-23. Large-P Variable Selection in Two-Stage Models. https://arxiv.org/abs/2003.10484

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