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Title: Clustering spatial functional data using a geographically weighted Dirichlet process
We propose a Bayesian nonparametric clustering approach to study the spatial heterogeneity effect for functional data observed at spatially correlated locations. We consider a geographically weighted Chinese restaurant process equipped with a conditional autoregressive prior to capture fully the spatial correlation of function curves. To sample efficiently from our model, we customize a prior called Quadratic Gamma, which ensures conjugacy. We design a Markov chain Monte Carlo algorithm to infer simultaneously the posterior distributions of the number of groups and the grouping configurations. The superior numerical performance of the proposed method over competing methods is demonstrated using simulated examples and a U.S. annual precipitation study.  more » « less
Award ID(s):
2412922 2412923 2210371
PAR ID:
10598227
Author(s) / Creator(s):
; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Canadian Journal of Statistics
Volume:
52
Issue:
3
ISSN:
0319-5724
Page Range / eLocation ID:
696 to 712
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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