About the project – for general public

About PerFake project

Research project “PerFake – Reducing belief PERseverance in the context of FAKE news and misinformation” aims at reducing the negative impact of fake news and misinformation on individuals and society. The following video provides a general overview of the project.

Project aim

Decision making shapes important outcomes for individuals and society. If decisions are influenced by fake news and misinformation [1], they are likely to be suboptimal. Salient examples are the decisions related to the COVID-19, climate change, Brexit, or the 2016 US presidential election. Misinformation and fake news have always been a part of our society. However, the internet and the rise of social media platforms have facilitated their spread.

According to the Eurobarometer on fake news and online disinformation, 37% of the respondents come across fake news every or almost every day, and 83% of the respondents believe that fake news represents a danger to democracy.

According to the survey of the American Institute of CPAs, 58% of Americans perceive fake financial news as a serious threat to their financial decision making and 63% of Americans say that the spread of fake news has made it more difficult to make critical financial decisions. Making sound financial decisions is crucial for achieving not only individual financial well-being but also financial market stability and a functioning economy. Countering misinformation and reducing its negative impact on individuals’ opinions and decisions is therefore of utmost importance.

Therefore, the overall objective of the PerFake project is to reduce the negative impact of fake news and misinformation on individuals’ opinions and thus contribute to making sound decisions for individuals and consequently for society.

The research shows that simple retraction or correction of misinformation is insufficient to eliminate its influence; misinformation may continue to influence our judgment and reasoning even after it has been retracted. One of the reasons for the failure of simple retractions is the belief perseverance bias = “the tendency to persevere in beliefs or opinions even after the initial information on which the beliefs or opinions were based has been discredited” [2].

Nevertheless, only a few techniques for mitigating the belief perseverance bias have been developed, and the practical applicability of these techniques is limited. Therefore, to achieve the overall objective of the PerFake project, we aim at contributing to the research on the belief perseverance bias. In particular, we aim at developing debiasing techniques to mitigate the belief perseverance bias after the retraction of misinformation with a higher potential for practical applicability than the existing debiasing techniques.

Project results

We developed two debiasing techniques, counter-speech and awareness training, with higher practical applicability than the existing debiasing techniques. Their effectiveness in mitigating the belief perseverance after the retraction of misinformation was tested in two experiments. In the first experiment, we compared the techniques with an existing debiasing technique. We showed that the awareness-training technique performs as well as the existing debiasing technique, and the counter-speech technique performs considerably better than the existing debiasing technique in terms of effectiveness in mitigating the belief perseverance bias. In the second experiment, we compared the combination of the awareness-training and counter-speech techniques with the single debiasing techniques. We showed that combining the techniques is more effective in mitigating the belief perseverance bias after the retraction of misinformation than applying the single techniques.

To summarize, both debiasing techniques developed within the PerFake project and their combination effectively mitigate the belief perseverance bias after the retraction of misinformation. These debiasing techniques thus help reduce the negative impact of misinformation on individuals’ opinions and contribute to sound decision making.

Debiasing techniques

Counter-speech

The counter-speech debiasing technique consists in refuting the specific claim of misinformation or fake news. It requires a considerable effort from the providers of the debiasing as it needs to be adapted to the specific claim to be refuted. In particular, the providers of debiasing need to provide suitable arguments against the specific claim of misinformation or fake news.

The counter-speech debiasing technique consists in:

  1. warning the people that the claim (information, news, etc.) they have read or heard is false (misinformation or fake news),
  2. noting that there exist several arguments against the claim (i.e. counter-arguments),
  3. providing a few counter-arguments,
  4. asking the people to spend some time thinking about the provided counter-arguments and think of other possible counter-arguments.

Awareness training

The awareness-training debiasing technique consists in raising people’s awareness about the belief perseverance bias and its potential negative impact on their opinion in the presence of misinformation or fake news. The technique is universally applicable to any misinformation or fake news and, thus, requires only a little effort from the providers of debiasing.

The awareness-training debiasing technique consists in:

  1. warning people that the claim (information, news, etc.) they have read or heard is false (misinformation or fake news),
  2. pointing out that the misinformation or fake news should therefore have no influence on people’s opinion,
  3. introducing belief perseverance as a phenomenon responsible for irrational behaviour,
  4. illustrating the effect of belief perseverance on a particular example,
  5. warning the participants about the traps of belief perseverance.

We developed two different examples illustrating the effect of belief perseverance (step 4.) – one is a hypothetical real-life situation, and the other one is one of the most damaging medical hoaxes of the last 100 years, namely the alleged relationship between the measles-mumps-rubella (MMR) vaccination and autism.

Awareness training illustrating the effect of belief perseverance on a hypothetical real-life situation

This is fake news (misinformation). Now, as you know this, the fake (incorrect) information should theoretically have no influence on your opinion and decisions. Nevertheless, the opposite is likely to be true. It appears that people often insist on opinions even when they know that they are based on wrong information. This irrational behaviour is called “belief perseverance“.

The effect of belief perseverance can be illustrated by the following hypothetical real-life situation: Emily tells Oliver that the new fellow student Paul is not particularly clever and advises him against working in a group with Paul. After a few days, Oliver finds out that there was a misunderstanding and that Emily did not speak about Paul but Tim. If Oliver were to act rationally, he would now be completely free of prejudices against Paul since his original opinion about Paul turned out to be based on wrong information. Nevertheless, due to belief perseverance, Oliver continues to avoid working with Paul, even though he knows Emily has talked about someone else.

It is important that we create and change our opinion and make decisions freely without being manipulated by fake news (misinformation). Thus, we should be aware of this trap in the form of “belief perseverance” whenever we encounter fake news (misinformation).

Awareness training illustrating the effect of belief perseverance on the medical hoax concerning the MMR vaccination and autism

This is fake news (misinformation). Now, as you know this, the fake (incorrect) information should theoretically have no influence on your opinion and decisions. Nevertheless, the opposite is likely to be true. It appears that people often insist on opinions, even when they know that they are based on wrong information. This irrational behaviour is called “belief perseverance“.

The effect of belief perseverance can be illustrated by the most damaging medical hoax of the last 100 years. In 1998, a paper stating that the measles-mumps-rubella vaccine causes autism was published and triggered a lot of debate over vaccine safety. As a consequence, vaccination compliance dropped sharply in the years after the publication. Later, the paper was officially labelled as a fraud and fully retracted. Numerous well-controlled follow-up studies found no link between the vaccine and autism. If people were to act rationally, they would have to completely disregard the fraudulent information about the link between the vaccine and autism. Nevertheless, many parents still refuse to vaccinate their children, and members of anti-vaccine movements still promote conspiracy theories linking vaccination and autism.

It is important that we create and change our opinion and make decisions freely without being manipulated by fake news (misinformation). Thus, we should be aware of this trap in the form of “belief perseverance” whenever we encounter fake news (misinformation).


[1] The term misinformation broadly refers to information that is presented as true but later appears to be false, regardless of intent to mislead. The term fake news usually refers to false information that is intentionally designed to mislead.

[2] Citation from: Anderson, C. A. (2007). Belief Perseverance. In R. F. Baumeister & K. D. Vohs (Eds.), Encyclopedia of social psychology. Los Angeles, London: Sage, p. 109