When people talk about the sounds of a city, they're usually talking about noise—dense traffic, loud honking, music-pumping neighbors—and the ways to avoid it. But not all city sounds are unpleasant; some can inspire feelings of joy or calm, trust or anticipation.
Imagine if instead of asking your realtor for a quiet street, you asked for one where you could hear laughter, birds chirping and music drifting out of car windows. That's the idea behind Chatty Maps, a new sound mapping project from a Yahoo research lab in Barcelona. Unlike other projects that map cities by sound, Chatty Maps isn't measuring volume or ranking neighborhoods as noisy or quiet. Instead, it shows the city across a spectrum of different sounds—as well as the emotions we associate them with.
The researchers—Daniele Quercia from Bell Labs, Luca Maria Aiello from Yahoo, Rossano Schifanella from University of Turin, and Francesco Aletta from University of Sheffield—started by collecting sound-related words and checking them against social media data. To group the words into categories, they ran an algorithm through Flickr that automatically detected words that often occurred together. From there, they created five categories: transport (i.e., motorcycle, engine), nature (i.e., chirp, raining), human (i.e., talking, laughing), music (i.e., guitar, cello), and building (i.e., jackhammer). Using geo-tagged photos on Flickr, the team searched for the sound-related terms in the captions, then assigned each street a sound category. They also assign each category an emotion (anger, fear, anticipation, trust, surprise, sadness, joy, and disgust), based on Emolex, a word-emotion lexicon.
Here's what that looks like on a map: each street is coded with a color, and each color is assigned to a sound category (transportation, nature, human, etc.). Search for, say, bustling 5th Avenue in Midtown Manhattan, and you'll see that it's blue—meaning it's comprised of mostly human sounds. Click on it and a percentage pops up, showing you the ratio of other sounds mixed in. A circular key shows the emotions that are associated with these sounds, essentially calculating an "emotional profile" based on the sound percentages. In this case, 5th Avenue gives off vibes of joy and trust but also anticipation. Impressively, the researchers mapped this out for not only every street in New York, as well as the cities of London, Barcelona, Madrid and Boston.
Chatty Maps offers an alternate—and entertaining—way to look at the city where you live, but it also has some practical applications. The researchers imagine new wayfinding tools that not only offer the shortest route but also the one that's less of an auditory assault. Urban planners might use the information to go beyond mitigating noise—instead looking into ways to design a sonorous city that make us happier and less anxious. Ultimately, there are many ways the landscape of city can improve the well-being of its citizens—even through sound.
Cover Photo: Flickr user Kars Alfrink