Cabspotting for Inference

Here is one of the Exploratorium's coolest projects: Cabspotting (BoingBoing and Metafilter discussions). The visualization plots in real-time a cab (a circle glyph that is filled in only if the cab has a passenger with a comet trail where the cab has come from) in San Francisco and prior trips (phantom, wispy lines).

Now, let's consider the above screen capture that I made of their Flash client. There's a clump of cabs on Market Street and near The Embarcadero which is clearer on the Google map of San Francisco. The southernmost cab seems to be going from Market Street to pick up someone and the westernmost cab was doing the same and has picked up the passenger. From these data we can infer "cab intent," major areas of commerce, and traffic dynamics. For example, consider the amount of time and distance it takes the cab to pick up a passenger and with a bit of taxicab geometry we might discover short cuts.

You can email the fine folks from their FAQ page which provides more project extensions. I just emailed them for access to their API and Flash client. Perhaps I'll strap GPS to something and display that and more.