{"id":145270,"date":"2022-10-19T10:41:58","date_gmt":"2022-10-19T08:41:58","guid":{"rendered":"https:\/\/www.erasmusmagazine.nl\/en\/?p=145270"},"modified":"2025-12-19T11:26:28","modified_gmt":"2025-12-19T10:26:28","slug":"how-to-nudge-citizens-into-keeping-their-streets-clean","status":"publish","type":"post","link":"https:\/\/www.erasmusmagazine.nl\/en\/2022\/10\/19\/how-to-nudge-citizens-into-keeping-their-streets-clean\/","title":{"rendered":"How to nudge citizens into keeping their streets clean"},"content":{"rendered":"

How can you \u2018manipulate\u2019 residents into putting their garbage in the container or responding to letters about unjustified welfare payments? Malte Dewies worked on these and other issues as a collaboration between Erasmus University and the municipality of Rotterdam and turned this into his dissertation.<\/p>

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Malte Dewies did an experiment on nudging people to put their garbage in the container rather than next to it.<\/span><\/p>

\n\t\n\n<\/svg>\n<\/span>\n\tImage by:<\/span>\n\n\t\t\t\n\t\t\t\t\t\t\tLevien Willemse<\/a>\t\t\t\t\t<\/span>\n\t<\/p>\n<\/figcaption><\/figure>

Imagine you are at your aunt\u2019s birthday party; how do you tell people what your research is about?<\/strong><\/p>\n

\u201cI sometimes jokingly say it\u2019s about positive manipulation. That catches people\u2019s attention. But of course, in the end, it\u2019s not really about manipulation. It\u2019s about using psychological knowledge to make better policy and interventions that nudge people in the right direction.\u201d<\/p>\n

How did you conduct your research?<\/strong><\/p>\n

\u201cMy PhD was part of a collaboration between the municipality and Erasmus, in which we addressed policy issues on a case-by-case basis. You could describe us as internal consultants or advisors. For policymakers, having science-based advice is really useful. They would present us with a problem, after which we\u2019d investigate the behaviour, the policy issue and its context. Together with the policymakers, we\u2019d conduct the research, such as interviews or observations. We\u2019d then present solutions and try them out in the field. If that turned out positively, it meant we had created tools to address the issue. In total, we completed 25 projects.\u201d<\/p>\n

You did something with garbage?<\/strong><\/p>\n

\u201cThere was a big problem with people placing their garbage next to containers rather than inside them. The policy was that people from the municipality would go door-to-door, talk to the residents and inform them about the risks, fines and so on. Although residents did have the intention to keep their streets clean, not much changed. As part of a pilot in Oude Westen, residents were given a sticker after the talk to put up next to their front door. The sticker read: \u2018I will keep our street clean.\u2019 Such acts of commitment can help people follow through on their intentions and gives them a visible reminder every time they leave or go inside the house. Also, if you see a lot of those stickers in a street, you know what behaviour is expected and accepted. We then kept track of the days on which garbage was found next to containers and measured a two-thirds reduction.\u201d<\/p>\n

That\u2019s huge!<\/strong><\/p>\n

\u201cYes! I also worked on letters about unjustified welfare payments that had to be paid back. Almost 60 percent of people didn\u2019t respond to the letters. We found out that many of these people are in debt and have financial stress. So, in an updated letter, we reduced stress and simply encouraged debtors to contact the municipality \u2013 putting less emphasis on the repayment. That resulted in an increase of 4 percentage points more debtors who responded. That might sound small, but it is still significant.\u201d<\/span><\/p>\n\n\t

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\n\t\t\u2018You have to get your hands dirty sometimes and accept not having perfect experimental designs\u2019\n\t<\/blockquote>\n\n\t<\/figure>\n\t\t<\/div>\n\t<\/div>\n

You also researched the collaboration with the municipality itself. What did you find out?<\/strong><\/p>\n

\u201cListening to each other is key. Policymakers have different experience than scientists. Trying to convince policymakers of your views from an academic standpoint, as carriers of \u2018true knowledge and wisdom\u2019, doesn\u2019t work. Extremely useful and practical knowledge, insights and experience can be found outside of academia. The challenge is to bring scientific and practical knowledge together. For us, it helped to have a shared office where I worked a few days every week.\u201d<\/p>\n

\u201cAs scientists, we all know about the ivory tower and creating knowledge that is not very useful for society. But you have to get your hands dirty sometimes and accept not having perfect experimental designs. I would\u2019ve loved a randomised experiment for the letters, for instance, but that was impossible. We still did it, and this way, we developed an improved letter.\u201d<\/p>\n

How did you end up doing a PhD?<\/strong><\/p>\n

\u201cDuring my studies, I did an internship at the HR department of a large corporation. That was the direction I thought I was heading. Right next door was the United Nations, where the Global Climate Conference was held. Every morning, I got out of the subway, walked towards the UN building and got really enthusiastic about these policy issues and sustainability. But then I would take a right and head towards the corporate world, which I perceived to focus on individual careers and profit. I missed something there. This PhD was a good fit, as I enjoyed university life and it allowed me to help society.\u201d<\/p>\n

What did and didn\u2019t you like about the process?<\/strong><\/p>\n

\u201cI liked the freedom I had to choose and direct my research. I think that gave me room for some self-actualisation; I felt that I could own my PhD. However, everyone who says there are no downsides is probably lying. It took me quite a while to get my first publication out: three years. So, for some time, I was doubting myself and whether I could successfully complete my PhD. Also, collaborating with the municipality was extremely insightful and interesting, but it could also be challenging to align different interests.\u201d<\/p>\n

You wrote the shortest acknowledgements ever!<\/strong><\/p>\n

\u201cI actually wrote individual acknowledgements by hand to everyone I gave a book. Because I know that this book will never be on shelves in a bookstore, a professional look wasn\u2019t important to me. I wanted to make it a gift for friends and colleagues and personalise it. Otherwise, it\u2019s not really a gift. I can\u2019t draw \u2013 that would look ridiculous. So, inspired by painter Jackson Pollock, I wanted to splash paint on them like a mosaic. But that created some practical issues, so I just splashed them individually.\u201d <\/span><\/p>\n

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Malte Dewies wrote personal acknowledgement and made a different cover for every dissertation.<\/span><\/p>

\n\t\n\n<\/svg>\n<\/span>\n\tImage by:<\/span>\n\n\t\t\t\n\t\t\t\t\t\t\tMalte Dewies<\/span>\t\t\t\t\t<\/span>\n\t<\/p>\n<\/figcaption><\/figure>\n\t

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