Trees, cabs and crime in San Francisco
(Check out the big version!)
I've had this idea to use subtractive blending so that you can see
where these three data sets overlap for a while, and decided to
scratch the itch this weekend. I'm still not sure if it's significant
or even interesting, but here it is. This is a slightly improved
version of the original with a more useful (and attractive!) legend and no base map. The
colors have also changed: Trees are cyan and crimes magenta because I
felt that the latter should stand out more. And yellow combines with
magenta to produce red, which seems to me a more crime-y color.
Urban tree locations come courtesy of Friends of the Urban Forest, one day's worth of taxi cab locations from Yellow Cab (via Cabspotting), and a week's worth of reported crime incidents from Crime Reports.
Best, obviously, viewed at original size.
Comments and faves
antimega, skyvillain, chriswoebken, kev/null, and 76 other people added this photo to their favorites.
grex (52 months ago | reply)
This is fantastic! How did you create these? If you programmed this, what framework/language did you use?
aubergene (52 months ago | reply)
Very interesting, I've posted about it on theTimes Labs Blog.
Gadget Boy (52 months ago | reply)
Interesting, what software did you use to achieve this?
Shawn Allen (52 months ago | reply)
grex, Gadget Boy: This is actually a screenshot of a Flash piece that's not quite ready for prime time. Modest Maps provides the geographical projection math, and the rest is just 300 lines of hacky ActionScript 3.
I'd like to make it interactive eventually, but Flash isn't particularly well suited for moving this many points around on the screen (let alone keeping them in memory) at once, so I've resorted to progressively drawing each point to a bitmap rather than addressing them as individual vector objects. I'll probably end up either redoing it in processing or making bitmap tiles of each data layer independently and turning it into a slippy map.
aubergene: Thanks! FYI, the cab dots are GPS positions of taxis over a 12-hour period (specifically, 8am-8pm on Friday the 13th, 2009). And FUF's data describes meticulously recorded urban tree locations–i.e., planted trees along sidewalks, not (I'm almost certain) naturally occurring trees or those under the care of local and state parks.
CeciAllen (52 months ago | reply)
Amazing - I love your idea. Humm - GPS, could we track our route on Shadowfax?
-Jérôme- (50 months ago | reply)
hmm, aren't there more trees in Golden Gate Park???
Shawn Allen (50 months ago | reply)
Jerome: as previously noted, the tree locations are only those recorded by (and, I believe, under the care of) Friends of the Urban Forest. Trees in the city's parks are managed by SF Parks & Rec.
bradyf (46 months ago | reply)
Nice work as always.
loafcycle (43 months ago | reply)
great concept indeed,very good idea the additive cross references
campeau (14 months ago | reply)
I was never the brightest bulb, so can you help me understand how to read this? What can you infer with these overlaps of seemingly random datasets? Criminals take cabs but avoid trees? Victims flee in cabs or climb trees in a pinch?
julaville (13 months ago | reply)
at first I thought it said trees, CRABS, and crime... any data on crustacean consumption? I guess we are beyond the real season for it, though.
julaville (13 months ago | reply)
!
This photo was invited and added to the Thematic Mapping, Graphs and Geodata Visualization group.