Anyone who enjoys cycling in a big city knows the high risk of theft. Or did you have to experience yourself that the bike suddenly couldn't be found where you parked it: No lock is completely secure.
In Amsterdam, one of the most bike-friendly cities in the world, theft is becoming a public nuisance: tens of thousands of bikes are stolen every year – a significant chunk of the estimated 850,000 that Amsterdam residents own.
Where do all the stolen bikes go? Are they loaded into vans or trucks and sold elsewhere? Thrown in canals? Or are they simply reused by others in the city?
A team of researchers from the Massachusetts Institute of Technology (MIT) investigated these questions in collaboration with the Amsterdam Institute for Advanced Metropolitan Solutions. The results are now being published in the journal Plos One. For their experiment, the researchers equipped a total of 100 bicycles in the Dutch capital with mobile trackers and followed their routes for six months using GPS data.
The data showed that the majority of stolen bikes actually remain in the local area. "The most surprising thing for us was that it happened on the ground," says data scientist Fabio Duarte of MIT's Senseable City Lab, co-author of the study. “We thought the bikes would be stolen and sent abroad.” Rather the opposite is the case: “If they are stolen and sold, the new owner uses the bike in the same areas as the legitimate one did before. Probably without knowing it was stolen,” Duarte continues.
The MIT researchers have already used the GPS trackers, which are now hidden on the wheels, for various purposes. For example, to trace the illegal routes of electronic waste around the world. This time they have focused on a central problem in Amsterdam and many other cities, explains Carlo Ratti, Director of the Senseable City Lab, the motives. In Amsterdam, around 11,000 bikes are reported stolen every year; According to official estimates, there should be around 28,500, which is significantly more; some assumptions even assume 80,000.
The researchers equipped 100 used bicycles with trackers and parked them in public places. From the beginning of June 2021 to the end of November 2021 they followed the paths, during which time 70 bikes were stolen. The rate is still above the city average, which probably has to do with the chosen locations where they were parked.
Almost all the stolen bikes stayed in Amsterdam or in the surrounding area. About half a dozen were initially located near used bike shops, and researchers concluded that the stolen goods were sold there. 12 bikes ended up in locations known for black market trading.
It was also noticeable that 22 other bikes drove very similar routes. That too could have a system.
While the current study is not designed to track down the criminals, it does provide useful insights into how bicycle theft is organized in Amsterdam. With this inexpensive technology, typical patterns could be recognized, the MIT researchers explain. They have shared their findings with Dutch officials who are dealing with the issue. And maybe that will help track down the perpetrators in the future. Or at least their stolen goods.
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