PhD projects

Please email me to discuss any project or your own research ideas, or apply directly here. In your application make sure to give the project title and specify Prof. Richard Mann as the preferred supervisor.

Opinion dynamics of rational agents

with Prof. Richard Mann and Prof. Mauro Mobilia

NB: This project comes with funding to cover fees and stipend

Social media and other online communities are a maelstrom of competing ideas, memes and opinions. As these communities become a more and more central part of our social and political lives, identifying how and why some ideas spread and some don’t is crucial to understanding how the online world influences what we believe, what we do and how we vote. Models of opinion dynamics typically treat the spread of ideas like an epidemic, with individuals becoming ‘infected’ with a certain opinion and then passing it on to others. Indeed, observing how beliefs and opinions spread on social media it can often seem as though people have little control over which beliefs they adopt, and which they pass on. However, people are not simply passive recipients and vectors for ideas; expressing themselves online is a decision, and one that they make so as to accomplish their goals, whether conscious or not. In this project you will develop models of opinion dynamics based on the idea that the expression of ideas, opinions and beliefs is a choice made by rational agents in pursuit of specific goals. You will join a research team focused on understanding the collective behaviour of humans and animals in terms of rational decision-making theory. This PhD project will extend on previous and ongoing work [1, 2] by considering:

  1. The expression of an opinion as a decision. How does the expressed opinion relate to an agent’s true beliefs? What do people seek to accomplish by expressing it? What do we all want from our social media activity?
  2. What can we learn from social media and other online groups? What is the relationship between the truth and collective opinions online? How much should online opinion influence policy?
  3. How can problems with social media be tamed? Is there a role for ‘fact checking’? How can recommendation algorithms help or damage collective wisdom? Is more or less connectivity better for our online communities?

This is a mathematical programme of research that will be based on probability theory, especially Bayesian inference and optimisation. Stochastic processes, networks and game theory are also likely to be important. Applicants should be able to evidence a solid background in statistics and probability, and scientific programming. You will also engage with work from biology, psychology and sociology that provides a context for understanding human sociality, motivations and cognitive processes.

This work is related to ongoing projects in the group: Collective behaviour of cognitive agents; Rationality and reasoning beyond the individual

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