My project has focused on two main goals. The first goal was to test whether network modeling can be used to better predict which individuals change their beliefs about genetically modified food and childhood vaccinations. We were able to show that representing moral and social beliefs as a network and deriving a dissonance measure from this network representation results in more accurate prediction of which people change their beliefs. This measure outperformed more classical measures of belief dissonance in predicting belief change. The second goal was to develop a theoretical model of the interplay of personal and social beliefs affecting belief change. For this project, we developed a mathematically rigorous theory of belief change, validated the theory's core assumptions in empirical studies, and performed several simulations to show that this theory can explain established phenomena in the belief change literature. Empirical tests confirmed the core assumptions of our model: (a) Individuals, who want to reduce dissonance in their belief networks have more extreme beliefs, (b) individuals, who want to reduce dissonance in their social networks, showed little variance in how they perceived their friends' beliefs, and (c) individuals, who want to hold accurate beliefs, showed more extreme beliefs. Simulations showed that our model, which rests on the core assumptions that individuals want to reduce dissonance in their own belief network and in their social network, can reproduce several phenomena in the literature on beliefs, such as polarization, minority influence, and group radicalization.
These core projects and related results have been published in the following papers:
Dalege, J., Galesic, M., & Olsson, H. (2025). Networks of beliefs: An integrative theory of individual- and social-level belief dynamics. Psychological Review, 132, 253–290.
Dalege, J., & van der Does, T. (2022). Using a cognitive network model of moral and social beliefs to explain belief change. Science Advances, 8, eabm0137.
Galesic, M., Bruine de Bruin, W., Dalege, J., Feld, S. L., Kreuter, F., Olsson, H., ... & van Der Does, T. (2021). Human social sensing is an untapped resource for computational social science. Nature, 595, 214-222.
Galesic, M., Olsson, H., Dalege, J., Van Der Does, T., & Stein, D. L. (2021). Integrating social and cognitive aspects of belief dynamics: towards a unifying framework. Journal of the Royal Society Interface, 18, 20200857.
