Mobility indicator | Day selection | Definition of daily mobility indicator |
---|---|---|
MaxDist | R | Length of straight line connecting the home with the GPS fix furthest away from home |
CHull | R | Area of convex hull enclosing all GPS fixes |
SDE | R | Ellipse defined at one 1 SD containing approximately 68% of GPS fixes within the ellipse’s boundary |
LengthPerTrip | M | Average length of a move |
LocVar | R | Combined variance of X and Y coordinates [55] |
DurPTM | R | Time spent in passive transport modes |
TOH | R | Duration between all OH fixes, interpolating for up to 60-min gaps between consecutive GPS fixes if both fixes are OH |
Entropy | R | Entropy computed as in Saeb et al. [55]. Entropy measures how a participant’s time was distributed over the different stop locations: the higher the entropy, the more regularly time is distributed and/or the higher the number of unique locations |
NumLoc | R | Number of OH locations visited |
NumUniqLoc | M | Stops visited multiple times (referring to the same location cluster) during the included study days are only counted once |
DurATM | R | Time spent in active transport modes |
MaxDurATM | R | Duration of longest continuous trip using active transport modes |
RevisitedLS | M | Percentage of the daily convex hull that has overlap with any convex hulls of the other included study days |
AvgRevisitedLS | M | Average percentage overlap of the daily convex hull with the convex hulls of the other included study days |
SDDirMaxDist | M | Direction of most distant point from home. Weekly aggregation is done by circular SD: the larger the circular standard deviation, the more variability in day-to-day orientation of life space |
GravCompact | M | \(K = P/(2\sqrt {\pi A} )\) (where P = perimeter of convex hull and A = area of convex hull. The higher the more elongated is the life space |
Maj2MinAxis | M | Ratio between major and minor axis of standard deviational ellipse |
TimeMaxDist | M | Time of day starting at 3 AM [min] when most distant location from home is reached |
TimeFirstMove | M | Time of day starting at 3 AM [min] of the first move (approximation of first OH activity) of a day |
TimePeriodActive | M | Assignment of OH activities (moves and OH stops) based on start time to the classes morning (6 AM–12 noon), afternoon (12 noon–6 PM), or evening (6 PM–11 PM). A day is coded as 1 (morning day) if morning activities > evening activities; as 3 (evening day) if evening activities > morning activities; 2 (neutral timing day) in all other cases |