Title
Statistical anomaly detection for individuals with cognitive impairments.
Abstract
We study anomaly detection in a context that considers user trajectories as input and tries to identify anomalies for users following normal routes such as taking public transportation from the workplace to home or vice versa. Trajectories are modeled as a discrete-time series of axis-parallel constraints ("boxes") in the 2-D space. The anomaly can be estimated by considering two trajectories, where one trajectory is the current movement pattern and the other is a weighted trajectory collected from N norms. The proposed system was implemented and evaluated with eight individuals with cognitive impairments. The experimental results showed that recall was 95.0% and precision was 90.9% on average without false alarm suppression. False alarms and false negatives dropped when axis rotation was applied. The precision with axis rotation was 97.6% and the recall was 98.8%. The average time used for sending locations, running anomaly detection, and issuing warnings was in the range of 15.1-22.7 s. Our findings suggest that the ability to adapt anomaly detection devices for appropriate timing of self-alerts will be particularly important.
Year
DOI
Venue
2014
10.1109/JBHI.2013.2271695
IEEE J. Biomedical and Health Informatics
Keywords
Field
DocType
cognition,medical disorders,statistical analysis,gps,running anomaly detection,cognitive impairments,anomaly detection,2d space,movement pattern,weighted trajectory,gait analysis,discrete-time series,n norms,time series,patient diagnosis,axis-parallel constraints
Anomaly detection,False alarm,Pattern recognition,Computer science,Gait analysis,Artificial intelligence,Cognition,Recall,Trajectory,Statistical analysis
Journal
Volume
Issue
ISSN
18
1
2168-2208
Citations 
PageRank 
References 
0
0.34
13
Authors
5
Name
Order
Citations
PageRank
Yao-jen Chang139647.11
Kang-Ping Lin2156.51
Li-Der Chou331038.42
Shu-Fang Chen4172.66
Tian-Shyan Ma500.34