Searcharxiv⌕ Search

arXiv subjects

Wensheng Zhu

Publications and source records attributed to Wensheng Zhu.

2 recordsLinked to original sources

Convergence analysis of a proximal-type algorithm for DC programs with applications to variable selection

We consider a minimization problem of the form $P(φ, g, h):$ $$\min\left\{f(x):= φ(x) + g(x) - h(x) \colon x \in \mathbb{R}^n\right\},$$ where $φ$ is a differentiable function and $g,$ $h$ are convex functions, and introduce iterative methods to finding a critical point of $f$ when $f$ is differentiable. We show that the point computed by proximal point algorithm at each iteration can be used to determine a descent direction for the objective function at this point. This algorithm can be considered as a combination of proximal point algorithm together with a linesearch step that uses this descent direction. We also study convergence results of these algorithms and the inertial proximal methods proposed by Maing$\acute{e}$ and Moudafi (SIAM J. Optim. {\bf 19}(2008), 397--413) under the main assumption that the objective function satisfies the Kurdika--Łojasiewicz property. The proposed algorithm is then applied to solve the variable selection problem in linear regression.

math.OC↗

Learning non-monotone optimal individualized treatment regimes

We propose a new modeling and estimation approach to select the optimal treatment regime from different options through constructing a robust estimating equation. The method is protected against misspecification of the propensity score model, the outcome regression model for the non-treated group, or the potential non-monotonic treatment difference model. Our method also allows residual errors to depend on covariates. A single index structure is incorporated to facilitate the nonparametric estimation of the treatment difference. We then identify the optimal treatment through maximizing the value function. Theoretical properties of the treatment assignment strategy are established. We illustrate the performance and effectiveness of our proposed estimators through extensive simulation studies and a real dataset on the effect of maternal smoking on baby birth weight.

stat.ME↗