Lam Clifford, Fan Jiangqing
Princeton University.
Ann Stat. 2008 Oct;36(5):2232-2260. doi: 10.1214/07-AOS544.
The generalized varying coefficient partially linear model with growing number of predictors arises in many contemporary scientific endeavor. In this paper we set foot on both theoretical and practical sides of profile likelihood estimation and inference. When the number of parameters grows with sample size, the existence and asymptotic normality of the profile likelihood estimator are established under some regularity conditions. Profile likelihood ratio inference for the growing number of parameters is proposed and Wilk's phenomenon is demonstrated. A new algorithm, called the accelerated profile-kernel algorithm, for computing profile-kernel estimator is proposed and investigated. Simulation studies show that the resulting estimates are as efficient as the fully iterative profile-kernel estimates. For moderate sample sizes, our proposed procedure saves much computational time over the fully iterative profile-kernel one and gives stabler estimates. A set of real data is analyzed using our proposed algorithm.
具有不断增加预测变量数量的广义变系数部分线性模型出现在许多当代科学研究中。在本文中,我们涉足了轮廓似然估计和推断的理论与实践两个方面。当参数数量随样本量增加时,在一些正则性条件下建立了轮廓似然估计量的存在性和渐近正态性。提出了针对不断增加参数数量的轮廓似然比推断,并证明了威尔克现象。提出并研究了一种用于计算轮廓核估计量的新算法,称为加速轮廓核算法。模拟研究表明,所得估计与完全迭代轮廓核估计一样有效。对于中等样本量,我们提出的方法比完全迭代轮廓核方法节省大量计算时间,并给出更稳定的估计。使用我们提出的算法分析了一组实际数据。