Figure 5

Differentiate indoor from outdoor static points. ^aWe found that 99.5% of outdoor static clusters lasted less than 2 hours. ^bAbout 2% (number) of outdoor static clusters (accounted for 21% of the total outdoor static time) lasted 1-2 hours. ^cWe found 77% of all the outdoor static clusters that satisfied the upper level rules (the rules above this criterion) lasted less than 5 minutes. ^dA home location was detected if the cluster included 12:00 AM or lasted for more than 24 hours assuming that the participants were at their home under such conditions. ^eThe spatial accuracy was 10 m for the GPS device without Wide Area Augmentation System. Thus the GPS points within 10 m of home are more likely indoor points. ^f We used 50 m as an approximate size of an apartment. ^gThe 2nd lowest speed of all the outdoor static cluster was 0 and 5% (number) of the indoor static cluster (accounted for approximately 15% of the total indoor time) was more than 0.1 km/h. ^hAbout 64% of the indoor clusters satisfied this rule with only 2 of 13 outdoor clusters being misclassified.