Title
Permutation-test-based clustering method for detection of dynamic patterns in Spatio-temporal datasets.
Abstract
Massive spatio-temporal data have been collected from the earth observation systems for monitoring the changes of natural resources and environment. To find the interesting dynamic patterns embedded in spatio-temporal data, there is an urgent need for detecting spatio-temporal clusters formed by objects with similar attribute values occurring together across space and time. Among different clustering methods, the density-based methods are widely used to detect such spatio-temporal clusters because they are effective for finding arbitrarily shaped clusters and rely on less priori knowledge (e.g. the cluster number). However, a series of user-specified parameters is required to identify high-density objects and to determine cluster significance. In practice, it is difficult for users to determine the optimal clustering parameters; therefore, existing density-based clustering methods typically exhibit unstable performance. To overcome these limitations, a novel density-based spatio-temporal clustering method based on permutation tests is developed in this paper. High-density objects and cluster significance are determined based on statistical information on the dataset. First, the density of each object is defined based on the local variance and a fast permutation test is conducted to identify high-density objects. Then, a proposed two-stage grouping strategy is implemented to group high-density objects and their neighbors; hence, spatio-temporal clusters are formed by minimizing the inhomogeneity increase. Finally, another newly developed permutation test is conducted to evaluate the cluster significance based on the cluster member permutation. Experiments on both simulated and meteorological datasets show that the proposed method exhibits superior performance to two state-of-the-art clustering methods, i.e., ST-DBSCAN and ST-OPTICS. The proposed method can not only identify inherent cluster patterns in spatio-temporal datasets, but also greatly alleviates the difficulty in selecting appropriate clustering parameters.
Year
DOI
Venue
2019
10.1016/j.compenvurbsys.2019.02.007
Computers, Environment and Urban Systems
Keywords
Field
DocType
Spatio-temporal clustering,Density-based,Permutation test,Dynamic patterns
Data mining,Cluster (physics),Permutation,Determining the number of clusters in a data set,Local variance,Earth observation,Cluster analysis,Resampling,Geography,DBSCAN
Journal
Volume
ISSN
Citations 
75
0198-9715
0
PageRank 
References 
Authors
0.34
0
5
Name
Order
Citations
PageRank
Qiliang Liu11229.00
Wenkai Liu201.69
Jianbo Tang363.21
Min Deng45123.80
Yaolin Liu59725.42