Washington, DC / Amsterdam, Netherlands - In light of the election and ballot victories of populist, anti-establishment movements, many people have been trying to better understand the behaviors and motivations of voters. Studying voter behavior on an EU treaty, social psychologists in the Netherlands found that knowledge overclaiming predicts anti-establishment voting, particularly at the radical right.

The results of their research is published in the journal Social Psychological and Personality Science.

"Politicians and citizens with strong anti-establishment views, including populist movements, often articulate their views with high confidence," notes van Prooijen. "This research puts that confidence into perspective and suggests that it may often be overconfidence."

Blaming the establishment apparently is a cognitively "easy" way of making sense of the problems that society faces, write Jan-Willem van Prooijen (VU Amsterdam) and Andre Krouwel (VU Amsterdam), coauthors of the study. They note that this occurs for both the political left and the political right, though it tends to appear stronger for the radical right.

Van Prooijen and Krouwel measured and analyzed voter knowledge and behavior before and after an April 6, 2016, Dutch vote that supported or opposed a European Union (EU) treaty. The treaty was a decision on establishing stronger political and economic connections between the EU and Ukraine.

Questions were sent to a panel of voters 6 weeks before the referendum, and people were asked to rate themselves on their understanding of the treaty, as well as answer factual questions about the referendum, and a survey on their political views. A total of 13,323 people completed the questionnaire.

Two days after the vote, Van Prooijen and Krouwel followed up with a second round of questions, asking whether people voted in the referendum and how they voted, with the results kept anonymous. This group of consisted of 5568 people from the original panel who voted and 2044 people who had not voted.

Comparing the responses with voter behavior and political leanings, they found that for each measurement point of self-perceived knowledge, the anti-establishment vote becomes 1.62 times more likely. Yet, an increase in actual knowledge decreases the likelihood of the anti-establishment vote by 0.85 per measurement point.

"The study does not show that anti-establishment voters are somehow less intelligent, or less concerned with society," says van Prooijen. "Future research may reveal whether the discrepancy between self-perceived understanding and actual knowledge is due to being uninformed or due to being misinformed."

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