Title
Unsupervised detection and analysis of changes in everyday physical activity data.
Abstract
Display Omitted A framework for detecting and analyzing changes in physical activity time series data.A method to evaluate if the detected changes are representative of a significant lifestyle modification.Evaluation based on synthetic data and real-world Fitbit data collected from older adults. Sensor-based time series data can be utilized to monitor changes in human behavior as a person makes a significant lifestyle change, such as progress toward a fitness goal. Recently, wearable sensors have increased in popularity as people aspire to be more conscientious of their physical health. Automatically detecting and tracking behavior changes from wearable sensor-collected physical activity data can provide a valuable monitoring and motivating tool. In this paper, we formalize the problem of unsupervised physical activity change detection and address the problem with our Physical Activity Change Detection (PACD) approach. PACD is a framework that detects changes between time periods, determines significance of the detected changes, and analyzes the nature of the changes. We compare the abilities of three change detection algorithms from the literature and one proposed algorithm to capture different types of changes as part of PACD. We illustrate and evaluate PACD on synthetic data and using Fitbit data collected from older adults who participated in a health intervention study. Results indicate PACD detects several changes in both datasets. The proposed change algorithms and analysis methods are useful data mining techniques for unsupervised, window-based change detection with potential to track users physical activity and motivate progress toward their health goals.
Year
DOI
Venue
2016
10.1016/j.jbi.2016.07.020
Journal of Biomedical Informatics
Keywords
Field
DocType
Change point detection,Data mining,Physical activity monitoring,Unsupervised learning,Wearable sensors
Data mining,Time series,Change detection,Wearable computer,Computer science,Health intervention,Unsupervised learning,Synthetic data,Change detection algorithms,Behavior change
Journal
Volume
Issue
ISSN
63
C
1532-0464
Citations 
PageRank 
References 
4
0.56
0
Authors
3
Name
Order
Citations
PageRank
Gina Sprint1245.10
Diane J. Cook25052596.13
Maureen Schmitter-Edgecombe340021.88