Automatic machine-learning based identification of jogging periods from accelerometer measurements of adolescents under field conditions.
    
    
        
    
    
        
        PLoS ONE 12:e0184216 (2017)
    
    
    
		
		
			
				BACKGROUND: Assessment of health benefits associated with physical activity depend on the activity duration, intensity and frequency, therefore their correct identification is very valuable and important in epidemiological and clinical studies. The aims of this study are: to develop an algorithm for automatic identification of intended jogging periods; and to assess whether the identification performance is improved when using two accelerometers at the hip and ankle, compared to when using only one at either position. METHODS: The study used diarized jogging periods and the corresponding accelerometer data from thirty-nine, 15-year-old adolescents, collected under field conditions, as part of the GINIplus study. The data was obtained from two accelerometers placed at the hip and ankle. Automated feature engineering technique was performed to extract features from the raw accelerometer readings and to select a subset of the most significant features. Four machine learning algorithms were used for classification: Logistic regression, Support Vector Machines, Random Forest and Extremely Randomized Trees. Classification was performed using only data from the hip accelerometer, using only data from ankle accelerometer and using data from both accelerometers. RESULTS: The reported jogging periods were verified by visual inspection and used as golden standard. After the feature selection and tuning of the classification algorithms, all options provided a classification accuracy of at least 0.99, independent of the applied segmentation strategy with sliding windows of either 60s or 180s. The best matching ratio, i.e. the length of correctly identified jogging periods related to the total time including the missed ones, was up to 0.875. It could be additionally improved up to 0.967 by application of post-classification rules, which considered the duration of breaks and jogging periods. There was no obvious benefit of using two accelerometers, rather almost the same performance could be achieved from either accelerometer position. CONCLUSIONS: Machine learning techniques can be used for automatic activity recognition, as they provide very accurate activity recognition, significantly more accurate than when keeping a diary. Identification of jogging periods in adolescents can be performed using only one accelerometer. Performance-wise there is no significant benefit from using accelerometers on both locations.
			
			
				
			
		 
		
			
				
					
					Impact Factor
					Scopus SNIP
					Web of Science
Times Cited
					Scopus
Cited By
					
					Altmetric
					
				 
				
			 
		 
		
     
    
        Publikationstyp
        Artikel: Journalartikel
    
 
    
        Dokumenttyp
        Wissenschaftlicher Artikel
    
 
    
        Typ der Hochschulschrift
        
    
 
    
        Herausgeber
        
    
    
        Schlagwörter
        Population-based Cohort; Obstructive Pulmonary-disease; Human Activity Recognition; Time-series Data; Physical-activity; Activity Monitors; Motion Sensors; Mortality; Exercise; Single
    
 
    
        Keywords plus
        
    
 
    
    
        Sprache
        englisch
    
 
    
        Veröffentlichungsjahr
        2017
    
 
    
        Prepublished im Jahr 
        
    
 
    
        HGF-Berichtsjahr
        2017
    
 
    
    
        ISSN (print) / ISBN
        1932-6203
    
 
    
        e-ISSN
        
    
 
    
        ISBN
        
    
 
    
        Bandtitel
        
    
 
    
        Konferenztitel
        
    
 
	
        Konferzenzdatum
        
    
     
	
        Konferenzort
        
    
 
	
        Konferenzband
        
    
 
     
		
    
        Quellenangaben
        
	    Band: 12,  
	    Heft: 9,  
	    Seiten: ,  
	    Artikelnummer: e0184216 
	    Supplement: ,  
	
    
 
  
        
            Reihe
            
        
 
        
            Verlag
            Public Library of Science (PLoS)
        
 
        
            Verlagsort
            Lawrence, Kan.
        
 
	
        
            Tag d. mündl. Prüfung
            0000-00-00
        
 
        
            Betreuer
            
        
 
        
            Gutachter
            
        
 
        
            Prüfer
            
        
 
        
            Topic
            
        
 
	
        
            Hochschule
            
        
 
        
            Hochschulort
            
        
 
        
            Fakultät
            
        
 
    
        
            Veröffentlichungsdatum
            0000-00-00
        
 
         
        
            Anmeldedatum
            0000-00-00
        
 
        
            Anmelder/Inhaber
            
        
 
        
            weitere Inhaber
            
        
 
        
            Anmeldeland
            
        
 
        
            Priorität
            
        
 
    
        Begutachtungsstatus
        Peer reviewed
    
 
    
        Institut(e)
        Institute of Epidemiology (EPI)
    
 
    
        POF Topic(s)
        30503 - Chronic Diseases of the Lung and Allergies
    
 
    
        Forschungsfeld(er)
        Genetics and Epidemiology
    
 
    
        PSP-Element(e)
        G-503900-003
G-503900-001
    
 
    
        Förderungen
        
    
 
    
        Copyright
        
    
 	
    
    
    
    
    
        Erfassungsdatum
        2017-09-20