# Reasoning about Consensus when Opinions Diffuse through Majority Dynamics

@inproceedings{Auletta2018ReasoningAC, title={Reasoning about Consensus when Opinions Diffuse through Majority Dynamics}, author={Vincenzo Auletta and Diodato Ferraioli and Gianluigi Greco}, booktitle={IJCAI}, year={2018} }

Opinion diffusion is studied on social graphs where agents hold binary opinions and where social pressure leads them to conform to the opinion manifested by their neighbors. Within this setting, questions related to whether a minority/majority can spread the opinion it supports to all the other agents are considered.It is shown that, no matter of the graph given at hand, there always exists a group formed by a half of the agents that can annihilate the opposite opinion. Instead, the influence…

## 31 Citations

On the Complexity of Opinion Consensus under Majority Dynamics

- MathematicsICTCS
- 2019

It is shown that if there are only two available opinions, no matter of the underlying social graph G = (N,E), there is always a group formed by a half of the agents that can annihilate the opposite opinion.

Optimal majority dynamics for the diffusion of an opinion when multiple alternatives are available

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- 2021

On the complexity of reasoning about opinion diffusion under majority dynamics

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Maximizing the Spread of an Opinion when Tertium Datur Est

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- 2019

Deciding whether there exists a dynamics that can spread the opinion white to at least k agents or can reach a consensus is shown to be intractable, formally $\NP$-hard and islands of tractability based on certain structural properties of the interaction graph are identified.

Dynamics of opinion formation under majority rules on complex social networks

- Computer ScienceScientific Reports
- 2020

It is revealed that in densely-connected social networks, all individuals tend to converge to having a single global consensus, however, in sparsely-connected networks, the systems may exhibit rich properties where coexistence of different opinions, and more interestingly, multiple steady states of coexistence can be observed.

Biased Opinion Dynamics: When the Devil is in the Details

- Mathematics, Computer ScienceIJCAI
- 2020

It is believed that the model proposed is at the same time simple, rich, and modular, affording mathematical characterization of the interplay between bias, underlying opinion dynamics, and social structure in a unified setting.

Lifting Majority to Unanimity in Opinion Diffusion

- Computer ScienceECAI
- 2020

The goal is to derive graphtheoretic features of the network that guarantee whenever a majority of individuals initially have the same opinion, they will eventually spread the opinion to all individuals.

Multi-Issue Opinion Diffusion under Constraints

- Computer ScienceAAMAS
- 2019

This paper studies the diffusion of constrained opinions on a social network as an iterated process of aggregating neighbouring opinions as well as identifying classes of integrity constraints on which propositionwise updates decrease the influence gap between nodes of the network and their influencers caused by the presence of an integrity constraint.

Multi-Issue Opinion Diffusion under Constraints

- Computer Science
- 2019

This paper studies the diffusion of constrained opinions on a social network as an iterated process of aggregating neighbouring opinions as well as identifying classes of integrity constraints on which propositionwise updates decrease the influence gap between nodes of the network and their influencers caused by the presence of an integrity constraint.

Opinion Diffusion in Competitive Environments: Relating Coverage and Speed of Diffusion

- MathematicsCOMPLEX NETWORKS
- 2019

It is shown that the final configuration of the network strongly depends on their relative speed of diffusion, and how the number of agents that will eventually adopt an opinion is related with the speed of propagation of that opinion is characterized.

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