Field evaluation of personal digital assistant enabled by global positioning system : impact on quality of activity and diary data

Tom Bellemans, Bruno Kochan, Davy Janssens, Geert Wets and Harry Timmermans (2008), ‘Field Evaluation of Personal Digital Assistant Enabled by Global Positioning System: Impact on Quality of Activity and Diary Data’, Transportation Research Record: Journal of the Transportation Research Board, No. 2049, Washington, DC, USA: Transportation Research Board, National Academy of Sciences, 136–43