Marian-Andrei Rizoiu

Marian-Andrei Rizoiu.

I am a Professor of AI and Behavioral Data Science at the University of Technology Sydney, where I lead the Behavioral Data Science lab, and Director of the Defence Innovation Network (DIN). My interdisciplinary research crosses computer and social sciences, blending psycholinguistics, digital communication and stochastic modelling to understand human attention dynamics in the online environment, the emergence of influence and opinion polarisation. I am a two-time finalist for the prestigious Australian Museum Eureka Prize for Outstanding Science in Safeguarding Australia (2024, 2025), and recipient of the Excellence Award and Academic of the Year at the 2023 Australian Defence Industry Awards. I have secured $12.1 million in research funding, including $8.56 million from Defence's Advanced Strategic Capabilities Accelerator (ASCA), to detect and model the spread of mis- and disinformation and its weaponised counterparts – information and influence operations.

Values as of August 2026.

Research

My research has made several key contributions to information operations detection, online misinformation prediction, and understanding the radicalisation pathways in online environments.

First, I have developed paradigm-shifting behavioural models for detecting state-sponsored information operations. My approach focuses on behavioural fingerprinting rather than content analysis, enabling detection that cannot be easily bypassed by adversaries. The IC-Mamba system predicts misinformation virality before it occurs, whilst the X-Troll framework provides explainable detection of state-sponsored agents using appraisal theory and linguistic analysis. Second, my lab’s detection algorithms are integrated into the NARRATE narrative-awareness dashboard, developed with the Defence Science and Technology Group. That work is directed at early warning, attribution and decision support.

See more about my research.

News

See the lab's news page for more recent news.

2026-08: I presented "Behavioural fingerprinting for detection and triage of covert IO agents" at ADSTAR 2026 in Adelaide, alongside Lin Tian's talk on hardening information-operation detectors against adaptive adversaries. I also joined the "ADSUN a National System" panel as Director of the Defence Innovation Network.

2026-07: I was promoted to Professor at the University of Technology Sydney.

2026-01: Our paper "DREAMS: A Social Exchange Theory-Informed Modeling of Misinformation Engagement on Social Media" by Lin Tian and Marian-Andrei Rizoiu was accepted at The Web Conference 2026 (WWW'26) in Dubai!

2025-09: Appointed Director of the Defence Innovation Network (DIN), a network of 9 NSW and ACT universities facilitating Defence capability transfer into the NSW industrial ecosystem, managing a $2.3M annual budget.

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Research topics.

My research asks how harmful information spreads online, and how it can be detected and countered before it causes real-world harm. The central move is a shift from content-based to behaviour-based detection. Rather than analysing what is said — which raises censorship concerns, requires language-specific tools, and is easily evaded by an adversary who simply changes wording — my methods analyse how information spreads: the behavioural signatures and propagation patterns that coordinated actors cannot hide without abandoning their objective. This makes detection language-agnostic and adversary-resistant, and it is what allows the methods to transfer across platforms and languages.

A second finding, arising from work funded by the Department of Home Affairs, is that misinformation is a problem of social belonging rather than a problem of information. Debunking a falsehood rarely changes minds, because people filter what they read through pre-existing worldviews and community allegiances. This has shifted policy approaches away from fact-checking alone and towards community-level intervention.

I also work on skills and labour markets. Using large collections of online job advertisements, I quantify how similar skills are to one another and build occupation-transition recommenders: which skills a worker can carry into a new occupation, which occupations suit a given set of skills, and where the training gaps lie. The same methods measure how effectively skills are deployed across a workforce.

Where this is heading

The through-line of my work is that online harm is a systems problem rather than a content problem. Whether the subject is a state-sponsored influence campaign, a misinformation cascade during a natural disaster, or a radicalisation pathway, the useful signal lies in how people and populations behave around information, not in the words themselves. That framing is what makes the research portable: a method built for one language and one platform should carry to the next, because it never depended on either to begin with.

Two commitments follow. The first is that detection is only half the problem. Knowing something is spreading is worth little without knowing how much time remains to act and which intervention would help, so my work aims increasingly at forecasting and at the design of interventions rather than at classification alone. The second is that these systems have to be explainable. An analyst or a policymaker cannot act on a score; they need to know why an account, a narrative or a community was flagged, and to be able to disagree with the answer.

I work at the boundary between computer science and the social sciences, which is where I think the interesting problems now sit. The mathematics is only useful insofar as it is disciplined by how people actually behave. My research is built and tested with government and defence partners, and it is meant to end up in the hands of the people who have to make decisions with it.

From research to impact

The research reaches beyond the academy through four channels:

  • National policy. Findings from my Department of Home Affairs research reframed misinformation as a problem of social belonging rather than information. Research commissioned by the NSW Department of Communities and Justice was then used to revise the communication toolkit deployed in their campaigns for young men at risk of radicalisation.
  • Operational tools. My lab’s detection algorithms are integrated into the NARRATE narrative-awareness dashboard developed with the Defence Science and Technology Group.
  • Field-shaping methods. The shift from content analysis to behavioural detection has been recognised by the field, including through the Best Paper Award at The Web Conference 2025.
  • A national research ecosystem. As Director of the Defence Innovation Network, I connect nine universities with Defence and industry.

Recognition

  • 2024 & 2025 — Finalist, Australian Museum Eureka Prize for Outstanding Science in Safeguarding Australia
  • 2025 — Best Paper Award, The Web Conference (WWW’25)
  • 2026 — Best Exploration Paper Award, BioNLP shared task (ACL 2026)
  • 2023 — Excellence Award and Academic of the Year, Australian Defence Industry Awards
  • 2022 — Best Application Paper Award, Advanced Data Mining and Applications (ADMA’22)
  • 2020 — PitchFest award for a disinformation prototype, NSW Smart Sensing Network
  • 2019 — CNRS IDEXLYON award for research excellence
  • 2012 — Best student paper award, IEEE International Conference on Tools with Artificial Intelligence
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Leadership.

Director, Defence Innovation Network

Since September 2025, I direct the Defence Innovation Network (DIN) — a consortium of nine NSW and ACT universities, funded by the NSW Government and Defence, that connects university research capability with Defence and the defence industry. I was appointed following competitive recruitment, and serve as one of the node directors of the national Defence Research Network (DRN), which Defence is establishing from the Australian Defence Science and Universities Network.

DIN runs competitive research calls across its member universities, places PhD interns in defence companies, and convenes industry forums and showcase events, on an annual budget of $2.3 million. DIN has brokered more than $100 million in external investment.

Research program leadership

I lead the UTS contribution to an $8.56 million portfolio of three interconnected projects funded through Defence’s Advanced Strategic Capabilities Accelerator (ASCA), spanning UTS, Macquarie University and Adelaide University, which together develop the science, the software and the operational integrations for detecting and countering information operations.

The portfolio was built deliberately, in stages: early Defence Science and Technology Group contracts developed the theory and algorithms; a $1 million Department of Home Affairs program produced operational prototypes; a DIN-funded project demonstrated the approach at regional scale in the Pacific; and the ASCA portfolio now scales it towards deployment.

University leadership and academic service

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Engagement and outreach.

Policy contributions

Public scholarship

I write for The Conversation — 18 articles reaching more than 264,000 readers, frequently republished by the World Economic Forum, ScienceAlert and Channel News Asia.

In the media

My research has attracted more than 1,200 media and social-media mentions (Altmetric, February 2026), including Bloomberg Businessweek, the BBC, the World Economic Forum, Nature Index and the Australian Financial Review.

Selected invited talks

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Grants, funding and projects.

Funding

I have secured $12.1 million in research funding, including $8.56 million from Defence's Advanced Strategic Capabilities Accelerator across three major projects. The work is supported by Defence and national-security agencies — ASCA, the Defence Science and Technology Group, the Office of National Intelligence and the Department of Home Affairs — alongside the Australian Research Council, state government, industry and philanthropy.

The portfolio was built in stages, each designed to earn the next: early contracts to establish the theory and the algorithms; operational prototyping with national agencies; demonstration at regional scale in the Pacific; and now large multi-institution programs that put the methods in front of the people who have to use them.

Selected funded research

Other funded research

Where the work is going

Most of my current portfolio concentrates on detecting and countering information operations and online misinformation, delivered with Defence, government and university partners in Australia and internationally. A second strand applies the same behavioural methods to skills and labour markets, supporting government workforce and training policy. A third and newer strand examines safety and rule-evasion in multi-agent AI systems.

Alongside the research I direct the Defence Innovation Network, which connects defence research across nine universities in New South Wales and the ACT and channels university capability into the defence industrial base.

Current projects, publications and software releases are listed on the Behavioral Data Science lab site.

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Team and supervision.

The Behavioral Data Science lab

I lead the Behavioral Data Science lab — five postdoctoral researchers and eight PhD students spanning computer science and the social sciences. The lab is both a research group and a professional-development environment: students and postdocs publish in top-tier venues while developing skills in grant writing, stakeholder engagement and policy translation. Lab successes include lead-authored papers at The Web Conference, AAAI and CIKM, the WWW’25 Best Paper Award, and publications in Nature Scientific Data.

Supervision record

I have graduated more than 35 research students, including 11 PhD completions. Alumni hold continuing academic positions at the National University of Singapore and Indiana University Bloomington, a postdoctoral position at the University of Southern California, and research-scientist roles in industry, including at Alibaba and the Burning Glass Institute.

Prospective students

The lab takes students from machine learning, applied statistics and computational social science, as well as those arriving from the social sciences who want to work quantitatively. My approach is to give students problems that matter to someone outside the university, and the room to make them their own. Current openings, expectations and lab details are kept on the lab site.

Earlier teaching

I have previously convened and lectured undergraduate and postgraduate courses at the Australian National University and at Lumière University Lyon, covering relational databases and data warehousing, document analysis, information retrieval and natural language processing, and numerical machine learning.

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Biography.

I am a Professor of AI and Behavioral Data Science with the Faculty of Engineering and IT in the University of Technology Sydney, and Director of the Defence Innovation Network.

At UTS

I joined UTS in February 2019 and have held each academic level here since.

  • July 2026 – present — Professor of AI and Behavioral Data Science, Faculty of Engineering and IT
  • September 2025 – present — Director, Defence Innovation Network
  • January 2024 – July 2026 — Associate Professor in Behavioral Data Science, Data Science Institute
  • July 2021 – January 2024 — Senior Lecturer in Behavioral Data Science, Data Science Institute
  • February 2019 – July 2021 — Lecturer in Computer Science, Faculty of Engineering and IT

Visiting and honorary appointments

  • 2019 — Visiting Professor, Imperial College London, United Kingdom
  • 2019 — Visiting Professor, Jean Monnet University & CNRS Hubert Curien laboratory, Saint-Étienne, France
  • 2018 — Visiting Professor, Max Planck Institute for Software Systems, Saarbrücken and Kaiserslautern, Germany
  • 2019–2023 — Honorary Lecturer, Australian National University
  • 2016–2021 — Honorary Research Scientist, Data61, CSIRO

Previously

Between March 2016 and January 2019, I was a Research Fellow, then Lecturer with the College of Engineering and Computer Science at the Australian National University in Canberra. I was equally affiliated with the Data61 unit of CSIRO, in the Decision Sciences team.

Between May 2014 and February 2016,I was a researcher within the National ICT Australia in Canberra Australia, working in the Optimization Research Group. I was equally an adjunct lecturer with the College of Engineering and Computer Science at the Australian National University in Canberra.

Between September 2013 and May 2014, I was a PostDoctoral researcher with the ERIC Laboratory, financed by the ImagiWeb Research Project. I was equally an assistant professor with the DIS Department, at the University Lumière in Lyon.

Between 2009 and 2013, I was a PhD student at the ERIC Laboratory with the University Lumière Lyon2, under the supervision of Stéphane Lallich and Julien Velcin. I defended my PhD thesis on June 24th 2013, with honours "Très Honorable".

In July 2009, I obtained my MSc (graduating first of promotion, with honours) in Data Mining and Knowledge Engineering from the Polytechnic School of the University of Nantes, France and wrote my Master’s Thesis on "Textual Data Clustering and Cluster Naming" after an internship at the ERIC Laboratory.

Between 2004 and 2009, I did my undergrad and obtained in September 2009 my Engineer Diploma (double diploma, in parallel with the French Master's) in System and Computer Engineering from the Faculty of Automatic Control and Computers of the Polytechnic University Bucharest, Romania.

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Publications.

A selection of the work I consider most significant, rather than the most recent. The complete list is maintained on the Behavioral Data Science lab publications page.

Information operations and misinformation

Modelling information diffusion

Skills, labour markets and people

Research student theses

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