论文标题
拉索回归中的随机加权
Random weighting in LASSO regression
论文作者
论文摘要
我们在不同的正则化参数下$λ_n$和适当的规律性条件下在拉索回归中建立了随机加权方法的统计特性。随机加权方法在观察中涉及重复对随机目标函数的优化,这是由于需要对贝叶斯后验采样的计算近似而动机。在套索回归的背景下,我们在目标函数(包括罚款项)中反复将分析师的随机权重分配给术语,并优化以获取随机加权估计器的样本。我们表明,现有方法具有有条件的模型选择一致性和有条件的渐近正态性,不同的增长率为$λ_n$,为$ n \ to \ infty $。我们提出了对可用随机加权方法的扩展,并确定所得的样本在生长维度设置中达到条件稀疏正态性和条件一致性。我们发现随机加权既具有近似 - 基督教和采样理论的解释。最后,我们通过广泛的仿真研究和基准数据示例说明了所提出的方法。
We establish statistical properties of random-weighting methods in LASSO regression under different regularization parameters $λ_n$ and suitable regularity conditions. The random-weighting methods in view concern repeated optimization of a randomized objective function, motivated by the need for computational approximations to Bayesian posterior sampling. In the context of LASSO regression, we repeatedly assign analyst-drawn random weights to terms in the objective function (including the penalty terms), and optimize to obtain a sample of random-weighting estimators. We show that existing approaches have conditional model selection consistency and conditional asymptotic normality at different growth rates of $λ_n$ as $n \to \infty$. We propose an extension to the available random-weighting methods and establish that the resulting samples attain conditional sparse normality and conditional consistency in a growing-dimension setting. We find that random-weighting has both approximate-Bayesian and sampling-theory interpretations. Finally, we illustrate the proposed methodology via extensive simulation studies and a benchmark data example.