NYC 311 with Turf by Morgan Herlocker.
From the post:
In this example, Turf is processing and visualizing the largest historical point dataset on Socrata and data.gov. The interface below visualizes every 311 call in NYC since 2010 from a dataset that weighs in at nearly 8 GB.
An excellent visualization from Mapbox to start a Friday morning!
The Turf homepage reports: “Advanced geospatial analysis for browsers and node.”
Wikipedia on 311 calls.
The animation is interactive and can lead to some interesting questions. For example, when I slow down the animation (icons on top), I can see a pattern that develops in Brooklyn with a large number of calls from November to January of each year (roughly and there are other patterns). Zooming in, I located one hot spot at the intersection of Woodruff Ave. and Ocean Ave.
The “hotspot” appears to be an artifact of summarizing the 311 data because the 311 records contain individual addresses for the majority of reports. I say “majority,” I didn’t download the data set to verify that statement, just scanned the first 6,000 or so records.
Deeper drilling into the data could narrow the 311 hotspots to block or smaller locations.
As you have come to expect, Mapbox has a tutorial on using Turf analysis.
If this hasn’t captured your interest yet, perhaps the keywords, composable, scale, scaling, will:
Unlike a traditional GIS database, Turf’s flexibility allows for composable algorithms that scale well past what fits into memory or even on a single machine.
Morgan discusses a similar project and the use of steamgraphs. Great way to start a Friday!