時空過程的配適研究;An efficient modeling approach for spatiotemporal processes

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/88503

Title:	時空過程的配適研究;An efficient modeling approach for spatiotemporal processes
Authors:	羅意昕;Luo, Yi-Sin
Contributors:	統計研究所
Keywords:	變量訊息;高斯過程;地理統計;空間預測;Covariate information;Gaussian processes;Geostatistics;Spatial prediction
Date:	2022-06-16
Issue Date:	2022-07-14 13:50:54 (UTC+8)
Publisher:	國立中央大學
Abstract:	空間迴歸分析中，如何將解釋變數有效地加入共變異結構中以獲取更精確的空間預測是本文感興趣的議題。本文提供一種矩陣分解的方法，將解釋變數引入共變異結構中並能保證共變異矩陣為非負定矩陣，然後透過最大概似估計法估計模型參數。此外，本文將參數估計的結果結合自我迴歸模型(Autoregressive model)用以推測下一個時間點的參數值，並依此建立對應的研究區域之空間預測曲面。透過數值模擬實驗得知，本文所提的方法較一般常用的泛克利金迴歸法(universal kriging)有較佳的預測表現。同時本文亦透過分析臺灣PM2.5濃度的資料說明所提方法的實用性。 ;In spatial regression analysis, how to incorporate possible covariates into the covariance structure and obtain a more accurate spatial prediction both are interesting issues. In this thesis, a method of matrix decomposition is proposed which not only can incorporate pos sible covariates into the covariance structure but also guarantees the resulting covariance matrix to be positive semidefinite. Then, model parameters are estimated by the maximum likelihood method. Based on the estimation results of model parameters and the autoregressive model, model parameter values and the corresponding predicted surface for the next time point can be obtained. Numerical results show that the proposed method is superior to the commonly used universal kriging method in terms of spatial prediction. Also, a real data example regarding the fine particulate matter concentration in Taiwan is analyzed for illustration.
Appears in Collections:	[Graduate Institute of Statistics] Electronic Thesis & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	148	View/Open

社群 sharing

Loading...