Joey O'Brien

Data Scientist/Consultant

Acadia (Quaternion Risk Management)


I am currently a PhD student at the Universty of Limerick where I work within the Mathematics Applications Consortium for Science and Industry (MACSI) supervised by Prof. James Gleeson working on describing the dynamics of complex systems through a combination of mathematical modelling alongside large-scale data analysis. These systems can range from memes, online threads to even Fantasy sports!


  • November 22nd, 2021: Delighted to see some of our work on Covid-19 modelling publushed in a special issue on ‘Data science approaches to infectious disease surveillance’ in Philosophical Transactions of the Royal Society A Link | Preprint.
  • October 22nd, 2021: Just out in Physical Review Research: Our work on Herbert Simon’s classical random-copying model and extensions to incorporate memory effects. Link.
  • May 14th, 2021: New in Physical Review Research - we take a deep dive into the emrgence of leader nodes across a large collection of empirical networks (open access). Link.
  • May 3rd, 2021: I was invited to write a blog for Oxford University Press on our recent work where we applied complex networks theory to the problem of ranking within the sport of snooker. Link.
  • March 7th, 2021: Just out in Journal of Complex Networks - our work on providing a ranking system to the sport of snooker (open access). Link.
  • March 4th, 2021: Our work on Fantasy Premier League has just been published in PLOS ONE, with some media coverage including New Scientist, The Times (London), The Daily Star, Today FM (radio interview), The Irish Examiner, The Irish Times, Irish Independent, Limerick Leader, Limerick Post, and Offaly Express. Link | arXiv.
  • Ferbruary 4th, 2021: If you’ve ever wondered about webscraping in R or the secrets to success in Fantasy Premier League (or both!) then check out this invited webinar I gave for the WhyR? foundation. Slides | Video
  • December 4th, 2020: Received a prize for best speaker at the 7th SIAM Irish Student Chapter Conference where I presented our work on ranking within complex systems. Slides | Video
  • September 10th, 2020: Our work on FPL has been featured in New Scientist.


  • Complex Systems
  • Networks
  • Data Science
  • Statistics
  • Quantitative Finance


  • PhD in Applied Mathematics, 2017-2021

    University of Limerick

  • BSc. in Financial Mathematics, 2013-2017

    University of Limerick


Recent Posts

A complex networks approach to ranking professional Snooker players

Can complex networks help us to identify the greatest snooker player of all time?

Covid-19 and the Irish Routine

What can we learn about how Covid-19 has changed Irish daily life from publicly available mobility data?

The maths of fantasy football

Can strategic use of the Bench Boost, Free Hit and Triple Captain chips really increase your points total?

Recent & Upcoming Talks

Spreading of memes on multiplex networks

A model for the spreading of online information on multiplex networks is introduced and analyzed using branching-process methods. We …

Sporting contests through the lens of complex systems: A data-driven approach

Multiple facets of society have been studied in recent times due to the emergence of large-scale datasets arising from digital traces …

What makes a good (fantasy) football manager? - webscraping and data analysis in R

Arising from the desire for spectators of sporting contests to obtain more enjoyment, Fantasy sports have become increasing popular in …

A Generalization of the Classical Kelly Betting Formula to the Case of Temporal Correlation

For sequential betting games, Kelly’s theory, aimed at maximization of the logarithmic growth of one’s account value, …

O’Sullivan, Hendry, Davies,...? A complex networks approach to ranking professional Snooker players

The question is often posed regarding who is the greatest competitor within a given sport resulting in endless debates without …