Title
Weighted spherical 1-mean with phase shift and its application in electrocardiogram discord detection.
Abstract
Detecting discords in time series is a special novelty detection task that has found many interesting applications. Unlike the traditional novelty detection methods which can make use of a separate set of normal samples to build up the model, discord detection is often provided with mixed data containing both normal and abnormal data. The objective of this work is to present an effective method to detect discords in unsynchronized periodic time series data.The task of discord detection is considered as a problem of unsupervised learning with noise data. A new clustering algorithm named weighted spherical 1-mean with phase shift (PS-WS1M) is proposed in this work. It introduces a phase adjustment procedure into the iterative clustering process and produces a set of anomaly scores based upon which an unsupervised approach is employed to locate the discords automatically. A theoretical analysis on the robustness and convergence of PS-WS1M is also given.The proposed algorithm is evaluated via real-world electrocardiograms datasets extracted from the MIT-BIH database. The experimental results show that the proposed algorithm is effective and competitive for the problem of discord detection in periodic time series. Meanwhile, the robustness of PS-WS1M is also experimentally verified. As compared to some of the other discord detection methods, the proposed algorithm can always achieve ideal FScore values with most of which exceeding 0.98.The proposed PS-WS1M algorithm allows the integration of a phase adjustment procedure into the iterative clustering process and it can be successfully applied to detect discords in time series.
Year
DOI
Venue
2013
10.1016/j.artmed.2012.10.001
Artificial Intelligence In Medicine
Keywords
Field
DocType
new clustering algorithm,iterative clustering process,discord detection method,ps-ws1m algorithm,traditional novelty detection method,discord detection,electrocardiogram discord detection,phase shift,proposed algorithm,special novelty detection task,phase adjustment procedure,weighted spherical,time series
Convergence (routing),Data mining,Time series,Novelty detection,Computer science,Effective method,Robustness (computer science),Unsupervised learning,Artificial intelligence,Cluster analysis,Periodic graph (geometry),Machine learning
Journal
Volume
Issue
ISSN
57
1
1873-2860
Citations 
PageRank 
References 
2
0.39
11
Authors
5
Name
Order
Citations
PageRank
Jun Wang11529.49
Fu Lai Chung2153486.72
Zhaohong Deng364735.34
Shitong Wang41485109.13
Wenhao Ying5223.78