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arXiv · 2402.14942

On Identification of Optimal Dynamic Treatment Regimes with Proxies of Hidden Confounders

Jeffrey Zhang·Eric Tchetgen Tchetgen
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Abstract

We consider identification of optimal dynamic treatment regimes in a setting where time-varying treatments are confounded by hidden time-varying confounders, but proxy variables of the unmeasured confounders are available. We show that, with two independent proxy variables at each time point that are sufficiently relevant for the hidden confounders, identification of the joint distribution of counterfactuals is possible, thereby facilitating identification of an optimal treatment regime.

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Jeffrey Zhang, Eric Tchetgen Tchetgen. 2024-02-22. On Identification of Optimal Dynamic Treatment Regimes with Proxies of Hidden Confounders. https://arxiv.org/abs/2402.14942

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