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2018 – PSY-GAMES EXPERIMENT GRANT Psychological Game Theory Summer School

2018 – AIREP Travelling Fellowship

2018 – FESTIVAL OF DOCTORAL RESEARCH - PGR Student Research Case, Informative Category

2022 - Awarded the University Teaching Qualification “Basiskwalificatie Onderwijs”, Vrije Universiteit Amsterdam

2022/2023 - Organiser of the Interdisciplinary Workshop of the Digital Society

2021 - Organiser of the Force of Gossip Talk Series – Spring and Autumn edition

2019 -  Invited presenter at STEM for BRITAIN, London, House of Parliament

Martina is mainly interested in how different factors can influence the emergence of pro-social behaviours in individuals and societies. She mainly focuses on the role of information, communication, and reputation in the emergence of cooperation, sustainable development, and opinion segregation patterns. Her research lies at the intersection of sociology, social psychology, and biology. In her work, she employs methods rooted in various disciplines, such as Agent-Based Models (largely used in biology and rapidly growing in the social sciences), and lab experiments (used primarily in sociology, economics, and psychology).

Martina is also a strong advocate of open and reproducible science, pre-registering her studies and providing full access to data and material to encourage transparency and replicability of research.

Keywords: Cooperation, Sustainable behaviours, Social Dilemmas, Agent-based modelling, Pre-registered, Open Access

Key projects

Climate change and sustainability (2023 - present)

Finding a way to promote a more responsible and sustainable use of the available resources is one of the focal points of current public debates on the environment. Through pre-registered between-subjects experiments, she evaluates the impact of monetary incentives (short-term intervention; monetary surplus when choosing the sustainable option) and psychological incentives (long-term intervention; being aware that the future generation will inherit the left-over resources) on the emergence of sustainable development.

To further improve our understanding of how this psychological incentive can support sustainable development, she is currently working on a meta-analysis that will shade light on the mechanisms underlying such processes.

Segregation in opinion dynamics (2022 - present)

Current events have highlighted the evolution and wide spread of conspiracy theories (e.g., vaccinations and 5G, the COVID-19 pandemic as a biological weapon program, etc). Often, supporters of conspiracies hold strong beliefs despite the large amount of evidence that may challenge or disprove them. Through Agent-Based Model, she investigates under which conditions a minoritarian belief (such as the one of a conspiracy) can grow and become majoritarian in a population of rational (Bayesian) individuals. By understanding how these minoritarian beliefs are formed, she aims at testing possible interventions to break these close groups and provide practical advice on how to deal with conspiracy theories.

Social network, information, and reputation towards cooperation (2019 - present)

Humans are often shown to cooperate with one another. Most of the mechanisms that foster cooperation among humans rely on reputation, which itself relies on the acquisition of information about other people’s behaviours. Gossip has been proposed as a cheap yet efficient tool to acquire information. But is gossip really that cheap for those who spread it and thus for the entire community? Using both Agent-Based Models and online experiments, she investigates how individuals’ reactions to information influence their future actions, depending on their interpretation of the information and the network structure. Further, she explores under which conditions (e.g., network structure and agents’ cognitive reasoning) high levels of cooperation amongst groups can be fostered and sustained through gossip. Finally, can universal cooperation (versus parochial one) be supported by the mere introduction of information flow? Using lab experiment, she examines how cooperation varies between in-groups and out-groups when individuals are working towards a communal goal depending on the information flow.

Key funded projects

Martina’s most recent line of research on sustainable behaviours has been funded by:

• University of Essex Seed Fund for “Green Choices and Sustainable Development” (£1054),
• Vrije Universiteit Amsterdam Seed Fund for “Making Sustainable Choices for the Next Generation” (€3000),
• University of Essex Seed Fund for “Making Sustainable Choices for the Next Generation” (£5000),
• Policy Support Fund from the University of Essex/Research England for “Understanding Public Support for Science-Based Policies” (£9236.32).

Martina’s work on information and reputation was supported by the European Research Council Consolidator Grant project “The unknown force: How gossip shapes the functioning and performance of organizational groups” (ERC 771391).

Martina’s work has been featured in mainstream outlets like The Conversation (), Forbes (), and Social Science Space ().

Testori, M., Hemelrijk, C. K., & Beersma, B. (2022). Gossip promotes cooperation only when it is prosocially motivated. Scientific Reports, 12(1), 1-12. IF:4.38 DOI: 

Testori, M., Eisenbarth, H., & Hoyle, R. B. (2022). Selfish risk-seeking can provide an evolutionary advantage in a conditional public goods game. Plos one, 17(1), e0261340. IF:3.24 DOI: 

Takács, K., Gross, J., Testori, M., Letina, S., Kenny, A. R., Power, E. A., & Wittek, R. P. (2021). Networks of reliable reputations and cooperation: a review. Philosophical Transactions of the Royal Society B, 376(1838), 20200297. IF: 6.24 DOI: 

Lo Iacono, S., & Testori, M., (2021). Who are We Trusting? A Category-Based Formalisation of Trust. In Trust Matters: Cross-Disciplinary Essays, 35

Dores Cruz, T. D., Nieper, A. S., Testori, M., Martinescu, E., & Beersma, B. (2020). An Integrative Definition and Framework to ÐÓ°ÉappÏÂÔØ Gossip. Group & Organization Management, 1059601121992887. IF: 3.94 DOI: 

Testori, M., Harris, T. O., Hoyle, R. B., & Eisenbarth, H. (2019). The effect of psychopathy on cooperative strategies in an iterated Prisoner’s Dilemma experiment with emotional feedback. Scientific Reports, 9(1), 2299. IF:4.38 DOI: 10.1038/s*8796-0

Testori, M., Hoyle, R.B. & Eisenbarth, H., (2019). How group composition affects cooperation in fixed networks: can psychopathic traits influence group dynamics? Royal Society Open Science, 6(3), 181329. IF:2.96 DOI:

• 8th International Conference on Computational Social Science (July 2023) “What matters most in supporting cooperation, the gossip content or the gossiper’s intention? Simulating motive interpretation in gossip dynamics”
• Trust Matter Workshop (November 2022) “Punishing or Praising Gossipers: How people interpret the gossip motives shapes its consequences”
• 17th Social Simulation Conference (September 2022) “Gossip promotes cooperation only when prosocially motivated”
• 8th Meeting of the Society for the Scientific ÐÓ°ÉappÏÂÔØ of Psychopathy (May 2022) “Selfish risk-seeking can provide an evolutionary advantage in a conditional public goods game”
• European Consortium for Sociological Research (Oct 2021) “Inequality, egalitarian motives, and collective action: an experimental study”