A new online tool created by researchers at the Massachusetts Institute of Technology (MIT) can help measure people’s subjective impressions of urban environments, which may have consequences on social behaviour.

The tool was tested in a study that selected urban images randomly from Google Street View to allow volunteer users to compare and choose the photo they considered that matched certain attributes.

The task was to rank locations based on a variety of criteria including which looked safer, which looked wealthier and which looked more unique, with the answers then algorithmically compiled to give each area a score on from one to 10. The results were then transformed into maps.

“Income inequality is invisible if it’s in a bank account, but if it’s expressed in assets, as homes and cars, it becomes experiential,” said study leader César Hidalgo of MIT and Macro Connections.

“And the question for me is whether the experiences of inequality can elicit behaviours. I don’t have any evidence that this is the case, but at least I can show that some cities provide a more unequal experience. I can at least hypothesize that this might be something that explains social tension or social stress.”

place pulse

Place pulse

Photos were taken from  New York and Boston in the United States and Linz and Salzburg in Austria, and researchers discovered a greater disparity between respondents’ opinions on class and safety in the US cities than in the Austrian cities.

One limitation of the tool is that most of the pictures were captured by Google early in the morning, meaning several areas look deserted, leading to false impressions.

Though it still must be honed, the tool is considered a good complement to the Broken Window Theory developed by two Harvard University researchers in the early 1980s, which holds that urban disorder – visible signs of neglect such as broken windows – promotes crime, leading to a vicious cycle.

The theory, which was the basis for former New York mayor Rudy Giuliani’s suppression of minor crimes in NYC, received negative criticism from some social scientists who claimed that it was too difficult to quantify something as subjective as visible disorder. The new web tool could help solve that problem.

While the initial study ranked four cities ranked according to three attributes, the creators of the tool launched a website expanding their data base and studying neighbourhoods in 56 other cities around the world, ranking them based on how safe, wealthy, lively, depressing or boring they appear.

Quantifying cities emotional effects

Quantifying cities emotional effects

Australian cities ranked well in this international ranking, with Sydney coming third in the safety category and Melbourne ranking fourth in safety and third in wealth.

Hidalgo hopes the information he and his team are collecting can help to guide policy decisions.

“One of the things that would be the most interesting in the long run is to overlay these maps with expenditures of government, narrowly defined by the things that affect how places look, such as repaving roads, building parks, or putting cables underground,” he said.