Quantifying Urban Liveliness
In the age where companies or even government increasingly uses data and algorithm as a move towards evidence-based decision making. Until recently, city planning, a discipline stretching for millenias, has largely escaped this trend. Modern cities in the US and around the world were planned using theories, sometimes ideological, that simply couldn’t account for the sheer complexity of interplay between people and infrastructure. Sociologist Jane Jacobs noted the decline of US city centers in 1950s and 60s, proposing a theory where vibrant city life requires four basic conditions: city districts must serve more than two function, city blocks must be small with dense intersections, buildings must be diverse in terms of age and form, and a district must have a sufficient density of people and buildings. However, the same lack of available tools and data made it hard validate her theory as well.
A team of researchers led by Marco De Nadai published a working paper where readily available data mining technique applied to social media, mobile phones, and land use data can be used to validate her theory in a cheaper and less resource intensive way. Instead of using expensive pedestrian surveys, call data record, Foursquare check ins, and OpenStreetMap are incorporated into the model built on traditional census and zoning data. The model was then tested to six cities in Italy: Rome, Naples, Florence, Bologna, Milan, and Palermo. The result largely confirms Jacob’s theory and paved a new way for future evidence-based city planning.
