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Behavioural Economist Christina Gravert: We can all use a little nudge


Awareness of global challenges such as climate change doesn’t always make us change our lifestyles and behaviour. Similarly, knowing smoking is bad for our health doesn’t necessarily make us quit smoking. Christina Gravert is a behavioural economist who thinks we sometimes need a little help – a nudge – to make the right choice.

Christina Gravert

At the beginning of a new year many of us want to make some changes in life, start eating healthier, or spend more time with our dear ones. But in practice, many of these promises are hard to implement. Why do we have such a hard time changing behaviour?

According to Christina Gravert, a post-doc researcher at the Department of Economics, University of Gothenburg, a lot of our behaviour consists of habits, things that we do each day without really thinking about them, like brushing our teeth before going to bed.

Understanding behaviour  

‘When people make New Year’s resolutions, for example, they focus on the outcome they want to change such as to quit smoking or lose weight. However, the behavior that leads to these outcomes is often just automatic results of triggers. If I have a beer I smoke, if I go for a “fika” I eat cake etc. Trying to resist a cinnamon roll lying in front of me is much more difficult than trying to avoid the trigger altogether. So what is really necessary to change behaviour is to change the trigger. One way of doing this is through commitment devices. For example, instead of meeting with colleagues for “fika” one could arrange to take a small walk outside together instead, says Christina Gravert.

The opposite of habits are things we never do or postpone, often things that takes an effort. In behavioural science this is called procrastination.

‘We put off changing our insurance to a better one because there is no prompt telling that now is the time to do it. Or we don’t go to the gym because we feel there is no time in our day for it. In this case we need to create triggers that push us to do this healthy behaviour until it becomes a habit’.

According to neo-classical economic theory people are rational, selfish and utility-maximizing individuals. Behavioural economists, on the other hand, are influenced by psychology and perceive that human decision-making is much more complex and influenced by for example social aspects such as norms and altruism and by changing preferences over time or by being afraid of risk. Christina Gravert explains:

‘In behavioural theory we talk about the present bias. This means that costs and benefits that occur in the present moment seem much larger to us than in the future, even if that future is only an hour later. Because the benefits of eating a chocolate right now seem so much higher than losing some weight in the future, we succumb and eat the cake, which we did not intend to that same morning and which we later regret. Despite our regret, when placed in the same situation again, we again go for the cake’.


Understanding the mechanisms of decision-making is crucial when creating policies to change people’s behaviour, for example to improve the health of the population or increase sustainability. In 2008 behavioural economist Richard Thaler and law professor Cass Sunstein launched the term nudge (meaning knuff or puff in Swedish) in their book "Nudge: Improving decisions about health, wealth, and happiness". Since then the interest for nudging has grown, not the least in the US, the UK but also in nearby countries like Denmark and Norway.

‘Decisions are never made in a vacuum. The order in which choices are presented, the default options, the incentives and even the time and frequency of prompting a choice all influence the outcome of the decision. The choice architects, the ones who design the framing of the choice, might utilize what we call libertarian paternalism. This means that without restrictions, penalties or extra costs people can be nudged towards a decision that is better for them or for overall welfare of society than a competing decision’, says Christina Gravert.

In marketing what is referred to as a nudge has been used for a long time. In a typical super market there are sweets placed near the cash register so that you easily can pick a chocolate bar while standing in a queue. But nudging is different than advertising or marketing.

‘Nudging, if done right, seeks to encourage socially desirable behaviour and behaviour that increases the welfare of either the individual or society, rather than purely trying to increase the profit for a company’.

Freedom of choice?

One thing that makes nudges so attractive is that they are relatively cheap and effective and don’t restrict people in their choices. Freedom of choice is something we highly value and has proven to be more effective when changing behavior, according to Christina Gravert. Forcing students to take vegetables at lunch will likely increase food waste and protest, but presenting the vegetables in a more attractive way and giving them a choice between carrots and celery will make them more likely to eat vegetables, even if they don’t know why. 

The "don’t know why" is what makes Nudging so successful because it works mostly in our sub-consciousness. We can’t actively think about making the "right" sustainable, healthy, social optimal choice in all of the million tiny choices we are confronted with each day. Usually, we just do what we always do and that could be less than optimal.

‘This subconscious influence is also the main criticism that proponents of nudging are facing. People are scared that they are being manipulated into doing something that they don’t want to do. Again, we need to remember that there are no context independent decisions, so all choice architects do is to think about how we can design this context in the best possible way. Furthermore, other than with traditional steering methods such as laws and penalties, nudging never forces anyone to behave in a way they don’t want to’, says Christina Gravert.

Nudges to increase vaccination rates

At the end of last year Christina Gravert went to Italy to discuss the decrease in uptake of vaccinations in the European Union. In many European countries the vaccination rates for childhood vaccination such as measles and rubella are declining. In order to find solutions to this problem behavioural economists and decision makers were brought together by the European Commission’s Joint Research Center. Christina Gravert was one of the scientists.

‘The task for us scientists was to identify possible reasons for this decline in vaccinations and then propose nudges in order to increase vaccination behaviour without increasing spending. Our role also consisted of educating policy makers on the current findings of decision theory and using this knowledge to update strategies that were already in place to make the more successful. Examples are changing the default in a form, changing the way statistics are presented or using reminders in an efficient way.’

Christina Gravert was surprised how well they took the researcher’s ideas in especially since behavioural economics and nudging were completely new to most of them.

‘Ideally, these collaborations would lead to ideas that can then be tested in a field experiment. A field experiment tests nudges in a real world setting with real people, without them knowing, that their behaviour is being observed. This way we get the best information on how our proposed nudges change decision making’.

Nudging in Sweden

So far nudging has not developed much among Swedish scholars and organisations. Why?
‘Companies and organisations are still a little unsure about what nudging really means and how it can be successfully implemented. Experiments provide amazing opportunities for governmental institutions or companies to find out what really works, but decision makers are hesitant of trying them out. The experiments that have been carried out with companies and organizations have provided exciting knowledge for them and for the researchers, but every country needs some leaders that are willing to try it first’, says Christina Gravert.

In Sweden the “Swedish Nudging Network” and “Nudging Sweden” are more or less a blog and corresponding Facebook groups at the moment, but the interest is growing daily. Recently the Swedish authority Naturvårdsverket released a report about nudging (see link below).

Christina Gravert believes that behavioural science and nudging will become more important in the future as we need to find new ways of influencing behaviour without using penalties or prohibition. She thinks most people want to do good and be healthy but due to stress, daily demands and laziness, there is not enough willpower to make these changes.

‘I have always derived pleasure from finding “win-win” solutions to common problems – making everyone better off with the least amount of effort and costs. This leads me to see challenges everywhere. And also I see potential for improvement, which I find quite exciting.’

Make a little change in people’s lives to make a huge impact on society

At present Christina Gravert among other projects works on the problem of curbing procrastination by sending reminders to potential donors of a Danish charity organisation. She is developing a model to explain how reminders can increase desired behavior, but too many reminders could lead to the opposite effect. Previously, she looked at the effect of deadlines on charitable giving. Christina Gravert plans to introduce students to nudging in the form of a "Nudgeathon" in Göteborg. The event is similar to a case-study competition where students compete to come up with a creative nudge to increase sustainability for a participating company.

‘It is the greatest reward when results of my research are used to design nudges and thus provide benefit to the society. I would love to continue to cooperate with firms and governmental institutions to conduct research that truly aims at solving real world problems', says Christina Gravert.

Christina Gravert is from Germany and holds a post-doc position at the Department of Economics, School of Business, Economics and Law, University of Gothenburg. Her doctoral thesis from Aarhus University in Denmark is titled: "Giving and Taking – Essays in Experimental Economics".

Link to Naturvårdsverkets report "Nudging - Ett verktyg för hållbara beteenden?" (A Swedish report with summary in English)