A new experiment in Amsterdam, a happy hunting ground for thieves, reveals where stolen bikes actually go.
As one of the most bike-friendly major cities in the world, Amsterdam, unfortunately, falls prey to bike thieves who steal tens of thousands of bikes annually. This represents a significant portion of the estimated 850,000 bikes owned by Amsterdam residents. The prevalence of bike theft in the city prompts some interesting inquiries: What happens to all the stolen bikes? Do they get sold elsewhere out of the city? Do they end up in canals, or are they simply repurposed by other individuals within Amsterdam?
Now, an experiment at MIT, done with the help of the Amsterdam Institute for Advanced Metropolitan Solutions, has found answers by putting mobile trackers on a fleet of Amsterdam bicycles and watching where they go over time. It turns out that most stolen bikes stay in the neighborhood, at least in Amsterdam. A sizeable portion seem to be sold again, which means the majority essentially remain in the city’s fleet of bicycles.
For co-author Fabio Duarte, “the most surprising thing was that it’s happening locally.”
They “thought bikes might be stolen and sent abroad.”
But they “found they are used in the same [locations]. If they’re stolen and sold, the new owner uses the bike in the same areas, probably without knowing it was stolen. There are so many bikes in Amsterdam, you’re likely never going to know it was yours.”
The findings were published today in PLOS ONE.
To better comprehend the global distribution of illegal electronic garbage, for example, the lab has started implementing smart tags, according to author Carlo Ratti.
In this project, they focused on stolen bikes, a major problem in Amsterdam and many other cities.
In recent years, around 11,000 bicycles per year have been reported stolen in Amsterdam; however, according to the city, the true figure is likely greater, at about 28,500 per year. Cycling enthusiasts believe the figure is significantly higher, at 80,000 each year. Regardless of the accurate estimate, bike theft is a risk that comes with bike-friendly urban planning.
“Almost everybody in Amsterdam, or even in Cambridge,” adds author Titus Venverloo, “if you ride a bike, has had the experience of leaving somewhere and not finding their bike.”
With the permission of the local authorities, the researchers equipped 100 used bicycles in Amsterdam with inexpensive tracking devices, locked them in common areas, and monitored them from the beginning of June 2021 until the end of November 2021. 70 of the bikes were stolen during that time, which is more than the projected Amsterdam average and is likely due to the fact that they were being stored in public areas.
The bike movement was also tracked by the study team. 68 of the 70 stolen motorcycles were still in the Amsterdam region. Researchers found that between three and six of them were sold at used bike stores since they were often seen in the area of such establishments. Another 12 bikes were taken to places where they are known to be sold illegally, which is called the bicycle black market.
The researchers discovered that an additional 22 bicycles exhibited movements that were similar enough to be considered part of the same “subnetwork” of bicycles.
“What we found is that,” adds Venverloo, “we can indeed investigate this and say something about the level of organization, by doing network analysis and really looking into the data.”
The study team adds that although the experiment did not provide answers for every bicycle and was not utilized to prosecute criminal cases, it did provide important details regarding the nature of Amsterdam’s bike-theft issue.
With this low-cost technology, Duarte claims, “at least you start seeing patterns.
“Now you know where to be focused.”
Officials in Amsterdam who are tackling the issue of bike theft have been given the study findings, and they may use the information to assist the city government take further action.
“It’s great news that they’re interested and they’ve seen the results,” Venverloo adds. “They can resolve if they need to work locally or collaborate with other cities. It’s given them insight about geographic boundaries.”
The research had nothing to do with the programs Dutch police already use to catch bike thieves. In fact, to protect people’s privacy, the team stopped collecting data once they saw clear patterns in a bike’s movement that suggested it was being used regularly by someone who might not have known it was stolen.
The experiment, according to the researchers, has potential implications beyond bicycle theft, such as the waste-tracking initiatives Senseable City Lab has taken on, which may follow other kinds of items that are susceptible to theft. The research also offers mobility pattern data that might be used in urban planning.
The Delft University of Technology’s Transport Institute, Senseable City Lab, and the Amsterdam Institute for Advanced Metropolitan Solutions all provided financial assistance for the study.
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