Contrarian effect in opinion forming: Insights from Greta Thunberg phenomenon

ABSTRACT

In recent months, the figure of Greta Thunberg and the theme of climate changings quickly became the focus of the debate. This has led to a polarization effect in opinion forming about the climate subject. Starting from the analysis of this phenomenon, we develop an opinion dynamics model in which several types of contrarian agents are considered. Each agent is supposed to have an opinion on several topics related to each other; thus, the opinions being formed on these topics are also mutually dependent. The aim of the paper is to investigate the indirect effects of contrarian agents on the collective opinion about these topics. Several numerical tests are presented in order to highlight the main features of the model.

KEYWORDS:

• Opinion dynamics
• agent-based model
• contrarian effect
• web scraping
• sentiment analysis
• collective phenomenon

Acknowledgments

The authors sincerely thank the anonymous reviewer for critical feedback that helped us to improve the clarity and precision of our results and presentation.

The authors would like to acknowledge Emiliano Cristiani, Fabio Camilli and Luigi Teodonio for their stimulating discussions and suggestions about the topic of the paper.

The first author is a member of the INdAM Research group GNCS. Moreover, the author thanks the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) for the financial support through 20021702/GRK2326, 333849990/IRTG-2379, HE5386/18-1,19-1,22-1 and under Germany’s Excellence Strategy EXC-2023 Internet of Production 390621612. The funding through HIDSS-004 is acknowledged.

The second author is a member of the Association for Mathematics Applied to Economics and Social Sciences (AMASES).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

¹ See https://developer.twitter.com/en/docs/basics/counting-characters.html. Accessed: 2019–05-31.

² This is a derogatory term coined by some Italian rightwing newspapers. It merges together the name Greta and an Italian word to denote a person of low intelligence.