PMC4503212_01
An example of all the activity space locations for a 16-year-old female non-user. See text for explanation of the symbology. Note that specific locations and paths have been spatially altered for privacy protection.
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F2
As an example of this symbolization strategy, Figure 2 shows a map of the activity space of a 16 year-old female substance non-abuser. In Figure 2, one can see that the perceived risky place is a club, that the reason it is perceived as risky is that (as the subject states) "there's always someone getting shot around there" and that the social network quality is 28 (indicating that the people the subject associate with at the club exert a positive influence not to use illicit substances). Figure 3 shows the map displayed in Figure 2 with the associated dialog boxes that support interactivity.
Interface devices of the QAV.
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F3
Figure 3 shows the map displayed in Figure 2 with the associated dialog boxes that support interactivity. Table of Contents, which lists the specific data layers displayed on the left pane of the ArcMap window in Figure 3, lists each of the features displayed and reports the categorical and/or numeric data values for each of the associated (non-text) variables. The legend can also be displayed at any time to assist in the reader's interpretation of the map.
PMC4503212_02
Activity space map of a 17 year old, female non-substance user.
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F4
For example, Figure 4 shows the activity space of a 17 year old female non-substance user.
PMC4503212_03
Activity space map of an 18 year old, female substance user.
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F5
We use the QAV to explore an outlier subject with a particularly high residual for the model specified in equation 1, an 18 year old substance user (AADIS=63) for whom the model estimates non-substance use and whose activity space is presented in Figure 5.
PMC4503212_04
Activity space maps of a 13 year old (left) and an 18 year old (right).
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F6
West Philadelphia and the older subject's routine locations are more spatially dispersed. While Figure 6 shows only two subjects, the difference in activity space pattern between the younger and older subjects is typical.
PMC4503212_05
Maps of risky places for substance users by age subgroups (top left: age 13-14; top right: age 15-16; bottom left: age 17-18; bottom right: age 19-20). Different age subgroups have different numbers of substance users and magnitude of spatial dispersion of risky places.
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F7
Figure 7 show maps of the perceived risky places for the substance users within each age group category.