×

Unified statistical inference for a nonlinear dynamic functional/longitudinal data model. (English) Zbl 07505542

Summary: Studying massive functional/longitudinal data, we adopt a flexible nonlinear dynamic regression method named the Semi-Varying Coefficient Additive Model, in which the response can be a functional/longitudinal variable, and the explanatory variables can be a mixture of functional/longitudinal and scalar variables. With the aid of an initial B-spline approximation, a local linear smoothing is proposed to estimate the unknown functional effects in the model. Existing methods of statistical inference for sparse data and dense data are significantly different. We therefore develop the asymptotic theories of the resultant pilot estimation based local linear estimators (PEBLLE) on a unified framework of sparse, dense and ultra-dense cases of data. Remarkably, we obtain the oracle properties as if other functions were known in advance. Extensive Monte Carlo simulation studies investigating the finite sample performance of the proposed methodologies confirm our asymptotic results. We further illustrate our methodologies by analyzing COVID-19 data from China.

MSC:

62-XX Statistics

Software:

FRegSigComp; fda (R)

References:

[1] Breiman, L.; Friedman, J. H., Estimating optimal transformations for multiple regression and correlation, J. Amer. Statist. Assoc., 80, 391, 580-598 (1985) · Zbl 0594.62044
[2] Chen, Z.; Gao, Q.; Fu, B.; Zhu, H., Monotone noparametric regression for functional/longitudinal data, Statist. Sinica, 29, 4, 2229-2249 (2019) · Zbl 1432.62137
[3] Chen, Y.; Yao, W., Unified inference for sparse and dense longitudinal data in time-varying coefficient models, Scand. J. Stat., 44, 268-284 (2017) · Zbl 1361.62020
[4] Fan, J.; Gijbels, I., Local Polynomial Modelling and Its Applications. Vol. 66 (1996), CRC Press · Zbl 0873.62037
[5] Fan, J.; Zhang, J.-T., Two-step estimation of functional linear models with applications to longitudinal data, J. R. Stat. Soc. Ser. B Stat. Methodol., 62, 2, 303-322 (2000)
[6] Ferraty, F.; Vieu, P., Nonparametric Functional Data Analysis: Theory and Practice (2006), Springer Science & Business Media · Zbl 1119.62046
[7] Hastie, T.; Tibshirani, R., Varying-coefficient models, J. R. Stat. Soc. Ser. B Stat. Methodol., 55, 4, 757-796 (1993) · Zbl 0796.62060
[8] Hu, L.; Huang, T.; You, J., Estimation and identification of a varying-coefficient additive model for locally stationary processes, J. Amer. Statist. Assoc., 114, 527, 1191-1204 (2019) · Zbl 1428.62394
[9] Hu, L.; Huang, T.; You, J., Robust inference in varying-coefficient additive models for longitudinal/functional data, Statist. Sinica, 31, 2, 773-796 (2021) · Zbl 1469.62429
[10] Huang, J. Z.; Wu, C. O.; Zhou, L., Varying-coefficient models and basis function approximations for the analysis of repeated measurements, Biometrika, 89, 1, 111-128 (2002) · Zbl 0998.62024
[11] Kim, S.; Zhao, Z., Unified inference for sparse and dense longitudinal models, Biometrika, 100, 203-212 (2013) · Zbl 1284.62536
[12] Liu, H.; You, J.; Cao, J., A dynamic interaction semiparametric function-on-scalar model, J. Amer. Statist. Assoc. (2021)
[13] Maity, A., Nonparametric functional concurrent regression models, Wiley Interdiscip. Rev. Comput. Stat., 9, 2, e1394 (2017) · Zbl 07914920
[14] Morris, J. S.; Carroll, R. J., Wavelet-based functional mixed models, J. R. Stat. Soc. Ser. B Stat. Methodol., 68, 2, 179-199 (2006) · Zbl 1110.62053
[15] Qi, X.; Luo, R., Function-on-function regression with thousands of predictive curves, J. Multivariate Anal., 163, 51-66 (2018) · Zbl 1408.62075
[16] Ramsay, J. O.; Silverman, B. W., Functional Data Analysis (2005), Springer · Zbl 1079.62006
[17] Ramsay, J. O.; Silverman, B. W., Applied Functional Data Analysis: Methods and Case Studies (2007), Springer · Zbl 1011.62002
[18] Rice, J. A.; Silverman, B. W., Estimating the mean and variance structure nonparametrically when the data are curves, J. Royal Stat. Soc. Ser. B(Stat. Methodol.), 53, 233-243 (1991) · Zbl 0800.62214
[19] Scheipl, F.; Staicu, A.-M.; Greven, S., Functional additive mixed models, J. Comput. Graph. Statist., 24, 2, 477-501 (2015)
[20] Şentürk, D.; Nguyen, D. V., Varying coefficient models for sparse noise-contaminated longitudinal data, Statist. Sinica, 21, 4, 1831 (2011) · Zbl 1225.62129
[21] Wang, J.-L.; Chiou, J.-M.; Müller, H.-G., Functional data analysis, Annu. Rev. Stat. Appl., 3, 257-295 (2016)
[22] Wu, C.; Chiang, C. T., Kernel smoothing on varying coefficient models with longitidinal dependent variable, Statist. Sinica, 10, 433-456 (2000) · Zbl 0945.62047
[23] Wu, H.; Zhang, J. T., Local polynomial mixed-effects for longitudinal data, J. Am. Stat. Assoc., 97, 883-897 (2002) · Zbl 1048.62048
[24] Xue, L.; Qu, A.; Zhou, J., Consistent model selection for marginal generalized additive model for correlated data, J. Amer. Statist. Assoc., 105, 492, 1518-1530 (2010) · Zbl 1388.62223
[25] Zhang, X.; Wang, J.-L., Varying-coefficient additive models for functional data, Biometrika, 102, 1, 15-32 (2015) · Zbl 1345.62104
[26] Zhang, X.; Wang, J.-L., From sparse to dense functional data and beyond, Ann. Statist., 44, 5, 2281-2321 (2016) · Zbl 1349.62161
[27] Zhang, X.; Zhong, Q.; Wang, J.-L., A new approach to varying-coefficient additive models with longitudinal covariates, Comput. Statist. Data Anal., 145, Article 106912 pp. (2020) · Zbl 1510.62197
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.