Modele dynamiki opinii dotyczące polaryzacji i ekstremizacji 
[Opinion dynamics models of polarization and extremization]

Guillaume Deffuant (Complex Systems Lab, INRAE, France)


In this talk, I will review three families of models that claim to account 
for opinion polarization or extremization and point out their relation with 
some cognitive biases. I will first consider the bounded confidence models 
with extremists or with repulsive interactions. I will present the relation 
of this model with the confirmation bias and some aspects of the discussion 
about sociological grounding of repulsive interactions.  The second family of 
models is based on the "argument communication theory" and I will particularly 
focus on its recent version that explicitly includes a confirmation bias. The 
third family of models is derived from the so-called Leviathan model, showing 
the particularity that agents hold opinions about each other. This model 
relates to the affective polarization. I will show that the study of this 
model led to the detection of a yet unknown cognitive bias on self-evaluation.