Semi-varying coefficient models with a diverging number of components

Semiparametric models with both nonparametric and parametric components have become increasingly useful in many scientific fields, due to their appropriate representation of the trade-off between flexibility and efficiency of statistical models. In this paper we focus on semi-varying coefficient models (a.k.a. varying coefficient partially linear models) in a ''large n, diverging p'' situation, when both the number of parametric and nonparametric components diverges at appropriate rates, and we only consider the case p=o(n). Consistency of the estimator based on B-splines and asymptotic normality of the linear components are established under suitable assumptions. Interestingly (although not surprisingly) our analysis shows that the number of parametric components can diverge at a faster rate than the number of nonparametric components and the divergence rates of the number of the nonparametric components constrain the allowable divergence rates of the parametric components, which is a new phenomenon not established in the existing literature as far as we know. Finally, the finite sample behavior of the estimator is evaluated by some Monte Carlo studies.

[1]  S. Geer,et al.  High-dimensional additive modeling , 2008, 0806.4115.

[2]  Larry A. Wasserman,et al.  SpAM: Sparse Additive Models , 2007, NIPS.

[3]  H. Zou The Adaptive Lasso and Its Oracle Properties , 2006 .

[4]  R. Tibshirani,et al.  Varying‐Coefficient Models , 1993 .

[5]  A. Welsh On $M$-Processes and $M$-Estimation , 1989 .

[6]  J. Horowitz,et al.  Asymptotic properties of bridge estimators in sparse high-dimensional regression models , 2008, 0804.0693.

[7]  C. J. Stone,et al.  Additive Regression and Other Nonparametric Models , 1985 .

[8]  D. Cox Nonparametric Regression and Generalized Linear Models: A roughness penalty approach , 1993 .

[9]  Susan A. Murphy,et al.  Monographs on statistics and applied probability , 1990 .

[10]  Jianhua Z. Huang,et al.  Polynomial Spline Estimation and Inference for Varying Coefficient Models with Longitudinal Data , 2003 .

[11]  Jianhua Z. Huang,et al.  Variable Selection in Nonparametric Varying-Coefficient Models for Analysis of Repeated Measurements , 2008, Journal of the American Statistical Association.

[12]  Jianqing Fan,et al.  Nonconcave penalized likelihood with a diverging number of parameters , 2004, math/0406466.

[13]  M. Yuan,et al.  Model selection and estimation in the Gaussian graphical model , 2007 .

[14]  S. Portnoy Asymptotic behavior of M-estimators of p regression parameters when p , 1985 .

[15]  Lixing Zhu,et al.  NONCONCAVE PENALIZED M-ESTIMATION WITH A DIVERGING NUMBER OF PARAMETERS , 2011 .

[16]  Jianqing Fan,et al.  Variable Selection via Nonconcave Penalized Likelihood and its Oracle Properties , 2001 .

[17]  H. Zou,et al.  One-step Sparse Estimates in Nonconcave Penalized Likelihood Models. , 2008, Annals of statistics.

[18]  V. Yohai,et al.  ASYMPTOTIC BEHAVIOR OF M-ESTIMATORS FOR THE LINEAR MODEL , 1979 .

[19]  Cun-Hui Zhang,et al.  The sparsity and bias of the Lasso selection in high-dimensional linear regression , 2008, 0808.0967.

[20]  Jianhua Z. Huang Local asymptotics for polynomial spline regression , 2003 .

[21]  Carl de Boor,et al.  A Practical Guide to Splines , 1978, Applied Mathematical Sciences.

[22]  P. J. Huber Robust Regression: Asymptotics, Conjectures and Monte Carlo , 1973 .

[23]  S. Portnoy Asymptotic Behavior of $M$-Estimators of $p$ Regression Parameters when $p^2/n$ is Large. I. Consistency , 1984 .

[24]  Runze Li,et al.  Variable Selection in Semiparametric Regression Modeling. , 2008, Annals of statistics.

[25]  R. Tibshirani Regression Shrinkage and Selection via the Lasso , 1996 .

[26]  J. W. Silverstein,et al.  Spectral Analysis of Large Dimensional Random Matrices , 2009 .

[27]  R. Tibshirani,et al.  Generalized Additive Models , 1991 .

[28]  Chenlei Leng,et al.  Shrinkage tuning parameter selection with a diverging number of parameters , 2008 .

[29]  Jian Huang,et al.  SCAD-penalized regression in high-dimensional partially linear models , 2009, 0903.5474.

[30]  J. Horowitz,et al.  VARIABLE SELECTION IN NONPARAMETRIC ADDITIVE MODELS. , 2010, Annals of statistics.