The topic of my thesis is Gossip, Reputation, and Honesty, and I am testing conditions of honest communication with laboratory experiments and with data containing dynamic interactions in networks.

Academic background

I have been enrolled in a Sociology BA and MA at the Corvinus University of Budapest. My studies there have allowed me to gain insight into several processes where social embeddedness plays a crucial role in human decision-making. I first met social networking analysis and analytical sociology here. During my MA studies, I joined the Research Center for Educational and Network Studies (RECENS) research group.

• BA in Sociology, Corvinus University of Budapest, Budapest, 2012.

• MA in Sociology, Corvinus University of Budapest, Budapest, 2014.

• PhD in Sociology, Corvinus University of Budapest, Budapest, 2016-.

Research Projects

In my doctoral thesis I examine well-known social dilemmas in which the conflict of interest between individuals does not allow the outcome which would best serve the collective interest. Probably everyone has heard of the tragedy of the commons (Hardin 1968), where decisions of individuals motivated by self-interest lead to overconsumption of the public good. In such games with conflict of interest between the parties, the best output for the group can be promoted by reputational hierarchies because they can facilitate partner selection. Since decisions in these situations are made simultaneously, players can persuade their partner to cooperate if they signal somehow that they will cooperate. Reputational signals function properly when individuals can rely on it in their decisions. Using laboratory experiments and text analytics tools, I am testing what mechanisms can promote a reliable reputation hierarchy in competitive environments – where individuals are interested in disseminating false information about others. More specifically, I am analyzing structural determinants (e.g. network characteristics) of reputation and of signaling costs.


Samu, F., Számadó, Sz. and Takács, K. Scarce and directly beneficial reputations support cooperation, BIORXIV/2019/788836

A human solution to the problem of cooperation is the construction and maintenance of informal reputation hierarchies. Reputational information contributes to cooperation by providing guidelines about previous group-beneficial or free-rider behavior of opponents in social dilemma interactions. How reputation information could be credible, however, when outcomes of interactions are not publicly known, remains a puzzle. In this study, we propose that credibility could be ensured if reputation is a scarce resource and it is not believed to be earned for direct benefits. We tested these propositions in a laboratory experiment in which participants played two-person Prisoner’s Dilemma games without partner selection, could observe some other interactions and could communicate reputational information about possible prospective opponents to each other. We found that scarcity is a necessary condition for reputation scores to be informative. While cooperation has not been sustained at a high level in any of the conditions, reputational information clearly influenced cooperation decisions. The possibility of exchanging third-party information was able to increase the level of cooperation the most if reputation was a scarce resource and contrary to our expectations, when reputational scores have been directly translated into monetary benefits.


Károly Takács [Senior Lecturer] and Szabolcs Számadó

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Kopparhammaren 2, Room 3032

Campus Norrköping

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